iEnvironmental Engineering Researchj
Vol.41 (2004)


Biogasification of rice straw by anaerobic co-digestion with sewage sludge
SAITO Shinobu, KOMATSU Toshiya, HIMENO Shuji, KUDO Kyohei, FUJITA Shoichi
Department of Civil and Environmental Engineering, Nagaoka University of Technology, JAPAN
[KOMATSU Toshiya] koma@nagaokaut.ac.jp
Many existing anaerobic digesters in sewage treatment plants have surplus capacity because they are operated at quite long retention times. Thus, anaerobic co-digestion of sewage sludge and other biomass using existing digesters may be an attractive method for the efficient biogas recovery from biomass. In this study, we focused on botanical biomass (rice straw) as unused resources and investigated the feasibility of anaerobic co-digestion of sewage sludge and rice straw. As rice straw is too solid to feed directly in anaerobic digestion, two pretreatment methods, physical ground and thermal pretreatment were examined. After pretreatment of rice straw, mesophilic digesters were operated at various mixture ratios of rice straw to sewage sludge at retention times of 30 days. The results were as follows; rice straw didnft have inhibitory effects on digestion of sewage sludge and stable digestion was achieved in all conditions; in order to get methane conversion from rice straw same as sewage sludge, mixture ratio of rice straw to sewage sludge was 1:0.5 in physical pretreatment (5 mm) and 1:1 in thermal pretreatment (120 , 15 min); COD concentrations increased whereas ammonia nitrogen concentrations decreased in the supernatant of digested sludge by feeding rice straw.

Dilution-free treatment of the food-processong wastes by a two-phase circulating methane fermentation process
*:Environmental Technology R & D Center, ATAKA Construction & Engineering, Co., Ltd.
**:Department of Civil Engineering, Graduate School of Engineering, Tohoku University
[OSAMU MIZUNO] osamu.mizuno@atakakogyo.co.jp
[YU-YOU LI] yyli@epl1.civil.tohoku.ac.jp
The dilution-free treatment of food-processing wastes by a two-phase circulating anaerobic process was investigated in this study. In this process, the food-processing wastes were diluted with the effluent from the methanogenioc reactor instead of dilution by adding tap water. The potato waste and the soybean waste were used as the food-processing waste. The C/N ratio was 32 and 13 for potato waste and soybean waste, respectively. The CODcr loading rate for the methanogenic reactor was 14.0 g/l/d for potato waste and 17.9 g/l/d for soybean waste. The methane content in biogas was 56% for potato waste and 62% for soybean waste. The high VS removal (89%) and total CODcr removal (88%) were achieved in potato waste treatment. On the other hand, the VS removal and total CODcr removal were 79% for soybean waste. No ammmonia inhibition of methnane production was observed in soybean waste degradation at NH4+ concentration of 3,900mgN/L. However, acetate was significantly accumulated at higher than 4,000 mg/L of NH4-N, indicating that the high concentration of NH4-N seriously inhibited methanogenesis.

A Simple Process Model on the Anaerobic Digestion Treatment of Municipal Sludge with Ooznation
Hidenari Yasui*, Kazuya Komatsu*, Rajeev Goel*, Akiyoshi Ohashi**, Hideki Harada**
* Kurita Water Industries ltd. R&D Division
**Department of Civil and Environmental Engineering, Nagaoka University of Technology
An anaerobic digestion process with ozonation was studied by conducting pilot-scale experiments for on-site reduction in withdrawal sludge quantities while improving the biogas recovery, using a mixture of primary and secondary municipal sewage sludge. High VSS digestion efficiencies of ca. 80% and corresponding much methane production were achieved at reactor SS concentration of 6.5%. An empirical first-order kinetic model reasonably predicted the VSS degradation rates in the steady state conditions. The model suggested that about 61-70% of VSS fraction in the sludge was biodegradable nature and their specific degradation rate highly depended on the sludge source. The specific degradation rate in the model was 0.243 day-1 (primary sludge), 0.101 day-1 (excess sludge) and 0.019 day-1 (ozonated anaerobically digested sludge). In contrast of highly VSS degradation, solubilization of inorganic compounds was very limited and accordingly high fraction of inorganic solids, mainly acid insoluble inorganics and iron compounds, were found to accumulate in the reactors. The part of heavy inorganic solids could be removed by centrifuging and thus concentrated into the sludge to be withdrawn. The sludge having low VSS/SS ratio gave less moisture content of dewatered sludge cake. A linier relationship was found between VSS/SS ratio and the moisture content.

High Rate Anaerobic Treatment of Liquid-fraction of Shouchu Stillage Waste by a Multi-staged Thermophilic UASB Reactor
YAMADA Masayoshi*, YAMAUCHI Masahito**, OHASHI Akiyoshi*, HARADA Hideki**
*:Department of Environmental Systems Engineering, Nagaoka University of Technology, JAPAN.
**:Department of Civil Engineering, Kagoshima National College of Technology, JAPAN.
[YAMADA Masayoshi] myamada@stn.nagaokaut.ac.jp
[HARADA Hideki] ecohara@vos.nagaokaut.ac.jp
A long-term continuous flow experiment was conducted to investigate the process performance of a thermophilic multi-staged UASB (MS-UASB) reactor for treatment of liquid fraction of an alcohol (Shouchu) distillery wastewater. A demonstration scale MS-UASB reactor having a working volume of 2.5 m3 was operated at 55 ?C for a period of over 400 days.
Even though Shouchu distillery wastewater is a typical seasonal campaign wastewater, the process shows superior capability in re-starting up. The reactor steadily allowed a significant high COD loading rate of 60 kg COD?m-3?d-1, which is equivalent to the influent strength of 10,000-20,000 mg COD?L-1 at an HRT of only 4-8 h, keeping COD removal of above 80 %. Methane gas concentration in the biogas was about 70-80% over the experimental period. A linear relationship (R2=0.99, 0.97) was found between removed COD and methane production (as a COD conversion value) in Phase 1 and Phase 2. The methane conversion ratio during continuous run with barley-made (Phase 1) and sweet potato-made (Phase 2) Shouchu wastewater were 95 % and 91 %, respectively.

Basic Study on Quality Improvement of the Sewage Sludge Compost by Hair-Decomposing Bacteria
Tsuneo YAMATO*CJunichi YAGUCHI**CTatsuya@NOIKE*
* Department of Civil Engineering, Graduate School of Engineering, Tohoku University, JAPAN
** Hachinohe National College of Technology, Department of Civil and Environmental Engineering, JAPAN
[Tsuneo YAMATO]yamato@epl1.civil.tohoku.ac.jp
[Junichi YAGUCHI]yaguchi-z@hachinohe-ct.ac.jp
[Tatsuya NOIKE]noike@civil.tohoku.ac.jp
In order to improve the quality of sewage sludge compost products, hair-decomposing bacteria were isolated and investigate their function on composting process, because much human hair remaining in sewage sludge compost causes deterioration in quality. The isolated strains on the agar plates served in hair and keratin liquid medium for measuring the generated amino acid concentration and observing the situation of hair decomposition microscopically. Three strains, including Bacillus sp. (No.5) and two actinomycetes (No.9 and No.10) were obtained as promising bacteria and their characteristics were examined through four experiments. From the results of time course experiments, No.10 got the highest rate of amino acid production of 1.834(g/Lday) from keratin. The temperature experiments showed that in the hair liquid medium the peak of the rate of amino acid production was at 25 and the minimum was at 50. The falling rate of No.5 by the effect of rising temperature was smaller than other two. The coefficient dependent on temperature which was analogous to the activation energy in Arrhenius equation was introduced to evaluate the effect of temperature. In addition, the results of the mixture of experiments and the pretreatment experiments were discussed.

Alpha-Amylase Activity of Solid Starch-Degrading Bacteria in Anaerobic Digested Sludge
Yoshitake HIGUCHI*, Akiyoshi OHASHI*, Hiroyuki IMACHI*, Hideki HARADA*
*:Department of Environmental System Engineering, Nagaoka University of Technology, JAPAN
[HIGUCHI Yoshitake] yhiguchi@stn.nagaokaut.ac.jp
[OHASHI Akiyoshi] ecohashi@vos.nagaokaut.ac.jp
During anaerobic treatment of solid wastes, relatively slow hydrolysis of organic solids is usually considered to be a rate-limiting step. In this study, alpha-amylase, one of the hydrolytic enzymes, was investigated for the elucidation of more precise mechanism on hydrolysis during solid waste treatment. Alpha-amylase activity of solid starch-degrading bacteria (SDB) was investigated through batch experiments in mesophilic condition with several different substrates and with distinction between cell-bound and cell-free alpha-amylase. Four new strains of SDB were isolated successfully. Monitoring of the isolated bacteria was done by fluorescence in situ hybridization (FISH). Results indicated that cell-bound alpha-amylase was mainly responsible for the hydrolysis of organic solids, suggesting that increasing the contact between microbial cells and solid substrates might improve the digestion processes. It was also observed that during the absence of substrate, activity of alpha-amylase of SDB was low, however, it increased as substrates like starch or maltose was introduced.

Control of Sulfate Reduction under Nitrogen Deficient Condition in a Natural Anaerobic Pond Process for Cultivation of Purple Non-Sulfur Bacteria as Protein Source of a Fishpond
*: Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, JAPAN
**: Environmental Science Center, The University of Tokyo, JAPAN
***: Department of Environmental Engineering, Faculty of Engineering, Kasetsart University, THAILAND
[Ryo HONDA] honda@env.t.u-tokyo.ac.jp
[Kensuke FUKUSHI] fukushi@esc.u-tokyo.ac.jp
Influence of nitrogen and sulfate concentrations in wastewater on a purple non-sulfur bacteria (PnSB) pond process were investigated. A laboratory-scale chemostat photobioreactor treating four types of simulated wastewater were tested with different combinations of nitrogen and sulfate concentrations. Rhodopseudomonas palustris and sulfate-reducing bacteria were detected by a fluorescent in-situ hybridization (FISH) technique using specific probes, and their population was quantified by pixel counting in fluorescent microscopic observations. As a result, ratios of Rpal686 on EUB338 probe were over 25% throughout the operation period. Average removal of dissolved organic carbon was 94% independent of nitrogen and sulfate concentrations. However, it was found to be difficult to suppress sulfate reduction, even in case that nitrogen-limited wastewater was fed.

Feasibility study of the pilot-scale sewage treatment system combining of UASB and aerated fixed bed reactor under ambient temperature
Haruhiko SUMINO*, Masanobu TAKAHASHI**, Takashi YAMAGUCHI**/***, Kenichi ABE****, Nobuo ARAKI****, Shinichi YAMAZAKI*****, Satoshi SHIMOZAKI******, Akihiro NAGANO*******, Naomichi NISHIO**/********
*: Dept. of Civil Eng. , Gifu National College of Technology
**: Hiroshima Prefectural Institute of Industrial Science and Technology
***: Dept. of Civil Eng., Kure National College of Technology
****: Dept. of Civil Eng., Nagaoka National College of Technology
*****: Dept. of Civil Eng., Kochi National College of Technology
******: New Product and Business Planning Office, Kotobuki Eng. & Mfg. Co., Ltd
*******: Environmental Systems Division, Sanki Eng. Co., Ltd.
********:Dept. of molecular biotechnology, Hiroshima university graduate school of advanced sciences of matter
[SUMINO Haruhiko] sumino@gifu-nct.ac.jp
A feasibility test of a 17 m3 pilot-scale sewage treatment system was carried out by continuous feeding of raw municipal sewage under ambient temperature conditions. The system consisted of an UASB and an aerated fixed bed reactor as a first unit and as a second unit, respectively. A part of the effluent from the fixed bed reactor was returned to the influent of UASB in order to supply sulfate sources. The total BOD of 148-162 mg/L at influent was reduced desirably to 11-25 mg/L at final effluents with a condition of the overall HRT of 24 hr and the recirculation ratio of 2-0.3 throughout the experimental period. The final effluent also showed superior quality with respect to low SS (10-32 mg/L) and high phosphorus removal efficiency. Vial activity tests of retained sludge in the UASB were conducted to evaluate an impact of temperature on the activity of microorganism. The methane-producing activities from acetate and H2/CO2 gas at 10 oC were only 2 % and 0 % of those at 35 oC, respectively. On the other hand, sulfate-reducing activities of the UASB sludge showed relatively high at 10 oC such as 18 % for acetate and 9 % for H2/CO2 gas compared to the activities at 35 oC . Therefore, BOD oxidization by sulfate reduction in the UASB could be dominant rather than methane production under low temperature condition. This sulfate-reducing activity tended to be proportional to the copy number of adenosine-5'-phosphosulfate (APS) reductase genes in DNA extracted from the sludge.

Ammonia volatilization from sawdust matrix in composting toilet
* Department of Sanitary and Environmental Engineering, Faculty of Engineering, Graduate School, Hokkaido University, JAPAN
** Department of@Environmental Resources ,Faculty of Agriculture, Graduate School, Hokkaido University, JAPAN
[ HOTTA SHINYA] zhenye@eng.hokudai.ac.jp
Composting toilet using sawdust as artificial soil matrix is an essential process in the onsite wastewater differentiable treatment system. It reduces volume of feces and urine by evaporating of water in feces and urine. And it can also attribute to nutrient recovery from human manure due to giving used sawdust that can be used as organic fertilizer rich in N, P and K. The aims of this paper are 1) to measure nitrogen balance in composting toilet and 2) to evaluate the effect of water evaporation on ammonia volatilization due to its high solubility into water. The nitrogen balance data obtained from the composting toilet operation showed that approximately 25% of nitrogen remained in the sawdust matrix and ammonia emission was always detected. The evaporation of water and ammonia volatilization occurred simultaneously from the composting toilet. In order to evaluate the effect of water evaporation on ammonia volatilization, the time course of pH and ammonia concentration in sawdust matrix were observed during ammonia volatilization process with and without evaporation of water. In the experiments, the rate of ammonia volatilization was greater than the rate of water evaporation in the first period and then the rate of ammonia volatilization decreased and become lower than water evaporation. This change in ammonia volatilization was caused mainly by pH value of water in the sawdust. Especially, at low water content the sawdust pH kept less than pH 6 even if ammonia concentration was high.

Characteristics of volatile fatty acids degradation and ecological significance of microbe in thermophilic methanogenic system fed with starch or protein as a carbon source
Daisuke TANIKAWA*, Takashi YAMAGUCHI*, Makoto ICHITSUBO*, Nobuo ARAKI**, Yasuharu TAKAHASHI**, Kazuaki SYUTSUBO***, Akiko MIYA****, Yuki NAGAYA****, Hideki HARADA*****
* Dept. of Civil Eng., Kure National College of Tech., JAPAN
** Dept. of Civil Eng., Nagaoka National College of Tech., JAPAN
*** Water and soil Environ. Div., Nat. Inst. Environ. Stud., JAPAN
**** Technologies, R. &D. Division, Ebara Corp., JAPAN
***** Dept. of Environ. Sys. Eng., Nagaoka Univ. of Tech., JAPAN
[Takashi YAMAGUCHI] yamaguti@kure-nct.ac.jp
[Daisuke TANIKAWA] s200355@st.kure-nct.ac.jp
We examined the characteristic of intermediate fermentation and ecological significance of microbe in thermophilic methanogenic system. Our study focused on ecological significance of sulfate-reducing bacteria contributing to propionate degradation, and the effects of the operating parameters such as pH level, COD loading and sulfate concentration on propionate accumulation. Six CSTRs were operated at a temperature of 55 and HRT of 25-75 days. As the results, propionate accumulation in the sulfate-rich reactor, "S-S", was found at 100-200 mg/L, which was 1/10 of the control reactor, "S-7". Community structure in hydrolysis and acid producing processes was examined by domain bacterial 16S rDNA targeted PCR-DGGE analysis. "Band B" or "Band P" on PCR-DGGE analysis found more starch- or protein-degrading bacteria, respectively, from all reactors. Fluorescence In-situ Hybridization was utilized for the identification of Thermophilic sulfate-reducing bacteria. By the analysis, Desulfotomaculum sp. was found in all CSTRs.

Relationship between the aircontaminants flying from the metropolitan area and the nitrogen concentration in mountain stream & rain water around Echigo Mountains
Toru AOI*, Kunihiro MORI**, Taro HIRANO**
*@ Civil Eng., Gunma College of Technology
** Naturalist
***President of the Chozo Goya mountain hotel
Dissolved nitrogen concentration of bulk precipitation and stream water were investigated on the Kabura river watershed (Western part of Gunma Pref.) and the Oze-numa lake. Also dissolved nitrogen concentration of stream (upper end of each river) around the Echigo Mountains including Fukushima, Niigata and Gunma Pref. were analyzed. NOx-N concentration showed most high value on the Kabura river watershed, and rather high value on the Tone river. In Niigata Prefectural side of Echigo Mountains, nitrogen concentration of the stream water lowered in 1/2 and in Fukushima side of that nitrogen concentration decreased to 1/5 level.
Rather high concentration of inorganic nitrogen on the upper stream of Tone River is thought to be derived from the air contaminants which come flying from the metropolitan area with the sea wind in summer.

Development of Absorption Photometer Using Tape Type Filter for Continuous Black Carbon Measurements
KATO Hideki*, MURAO Naoto*, YAMAGATA Sadamu*, OHTA Sachio*
* Division of Environmental Resources Eng., Graduate school of Eng., Hokkaido University
[KATO Hideki] kato-h@eng.hokudai.ac.jp
[MURAO Naoto] murao@eng.hokudai.ac.jp
Using tape type filter, an absorption photometer suitable for continuous absorption coefficient monitoring in remote area and black carbon (BC) monitoring in urban area was developed. This instrument is equipped with two fiber optic sensors, monitoring reflected light from aerosol collecting spot and non-collecting part of the filter. The latter signal was used as a reference to correct the shift of the sensor sensitivity caused by temperature fluctuations. Collection spot was automatically changed when the signal from the spot decreased below a threshold value. Measurements were conducted in Sapporo in October and November 2003 (period-I), and February and March 2004 (period-II) to evaluate and characterize the instrument. The good correlation between absorption coefficients measured by the instrument and EC concentrations measured by thermal method was found (R2=0.961 at period-I and R2=0.797 at period-II). One-hour BC concentrations calculated based on the regressions ranged from 0.5 to 7.8 mg/m3. The instrument was found to be easy to use and had sufficient sensitivity to be useful in atmospheric monitoring.

Estimation of Cancer Risk from Diesel Exhaust Particle (DEP) Based on NOx Data at Air Monitoring Stations in Sapporo, Japan
KATO Hideki*, MURAO Naoto*, YAMAGATA Sadamu*, OHTA Sachio*
* Division of Environmental Resources Eng., Graduate school of Eng., Hokkaido University
[KATO Hideki] kato-h@eng.hokudai.ac.jp
[MURAO Naoto] murao@eng.hokudai.ac.jp
Cancer risk from diesel exhaust particle(DEP) was estimated using data collected at ambient and roadside air monitoring stations in Sapporo. DEP concentrations were calculated based on the three assumptions: i)90% of ambient elemental carbon(EC) originate from DEP, ii)40% of DEP consists of EC, and iii)Human exposed DEP concentration is 80% of ambient DEP concentration. The cancer risks from polycyclic aromatic hydrocarbons (PAHs) and nitro-polycyclic aromatic hydrocarbons (NPAHs) were compared to the cancer risk from DEP (1.3~10-3 in summer and 1.5~10-3 in winter). The sum of the cancer risks from five PAHs and three NPAHs (1.1~10-7 in summer and 4.1~10-7 in winter) was much less than that from DEP. The correlation between EC and available data(NOx and SPM) at the air monitoring station in Sapporo was examined. EC and NOx showed higher correlations (R2=0.583 (summer), 0.775(winter)) than EC and SPM. DEP cancer risks were calculated for each air monitoring stations with the regression between EC and NOx. The risks for the ambient air monitoring stations and roadside air monitoring stations ranged from 8.4~10-4 to 1.5~10-3 and 1.4~10-3 to 2.5~10-3, respectively.

In Situ Permeable Wall For Hydrogenotrophic Denitrification of Groundwater
Tatsuya DOI*, Yutaka SAKAKIBARA**
*: Department of Civil and Environmental Engineering, Faculty of Engineering, Graduate School, Waseda University, JAPAN
**: Department of Civil and Environmental Engineering, Waseda University, JAPAN
[DOI Tatsuya] tatsuya.d@suou.waseda.jp
[SAKAKIBARA Yutaka] sakaki@mn.waseda.ac.jp
In this study, the performance of permeable walls that can achieve denitrification reaction by injecting H2 gas was studied experimentally and theoretically. In laboratory-scale sandy aquifers, permeable walls were constructed with sand, gravels, and two other granules. Groundwater containing about 25mg-N/l of NO3- with some nutrient was fed continuously at various HRTs, and measurements of nitrate, nitrite, DO and pH were made over one year. Experimental results showed that all permeable walls could remove nitrate without accumulation of nitrite. However, the performance was different in four permeable walls. From this result, we found that the performance of permeable walls was influenced by the diameter of granule. We analyzed denitrification reaction rates using a mathematical model developed according to conventional mass balance and kinetic theory. The analysis showed that the denitrification performance of walls having relatively higher KLa value was lower than the model predictions. It was thought that these low performances resulted from plugging by microorganisms, as larger difference existed in higher biomass and higher dissolution rate conditions. Therefore granule in the permeable wall should be selected with consideration of volumetric mass transfer coefficient and plugging in walls.

Effect of Iron Coagulant on Respiratory Activity of Activated Sludge
Iori Mishima*CMotoharu SUZUKI**CJun Nakajima*CMitsumi KANEKO*
*@Faculty of Science and Engineering, Ritsumeikan University
** Hyogo prefectural institute of public health and environmental sciences
[Jun Nakajima] jnakajim@nisiq.net
In order to remove phosphorus or control bulking, coagulants are sometimes added into the activated sludge process. Fe salts and Al salts are usually used as coagulant because they empirically have no influence on the removal efficiency. However, precise influences of coagulants on the respiratory activity of the activated sludge have not been clear yet. Firstly, the measurement method of dehydrogenase activity was discussed in this paper. Secondly, the influence of shock load of ferric chloride on the respiratory activity of the activated sludge was discussed from the batch experiments by measuring dehydrogenase activity and oxygen uptake rate.
The respiratory activity of the activated sludge decreased with ferric chloride addition. Decrease of pH, increase of Cl- concentration and increase of Fe concentration were suggested to decrease respiratory activity. The effect of increase of Cl- and Fe concentration was found to be negligible at actual condition. However, respiratory activity was sensitive to the change of pH and it was decreased rapidly with decrease of pH. It is necessary to prevent the decrease of pH value by alkalinity addition in order to maintain the respiratory activity.

The efficiency upgrading of denitrification device using rotating meshed plates reactor focusing the effect of diffusion layer
Sumio MASUDA*, Masahito YAMAUCHI**, Mohd Fauzi Bin Abdul Aziz***,
Tomoo SEKITO* and Kenji FUJIMOTO****
*Dept. of Civil & Environmental Engineering, University of Miyazaki
**Dept. of Civil Engineering, Kagoshima National College of Tech.
***Shinseigiken Eng. Co., Ltd
****Kiyomoto Co.,Ltd.
As the United States and Europe is limiting the discharge of nitrate, this steps will be definitely be followed by Japan. Nitrogen and Phosphorous in wastewater has been recognized to cause problems such as etroprication and at present, there is no effective treatment method to treat such wastewater. A rotating meshed plates denitrification reactor was developed focusing on reducing liquid film diffusion layer that offers diffusional resistance from the bulk liquid to the biofilm surface.
Artificial wastewater and methanol as carbon source was used for this experiment and the following results were obtained : In experiment using wire rod with 3mm of diameter and 10 cm long; 1) At 30rpm of rotating speed and 40 min of retention time, above 90% of denitrification rate has been achieved. 2) Compare to other denitrification reactor, achievement of a high denitrification rate when using the developed reactor for this study was because the diffusional layer is very thin. 3) In low rotating speed, a microorganism was proved to block the holes of the meshed plates. In experiment using wire rod with 1mm of diameter and 10 cm long; 4) At 15mg/L and 30mg/L concentration of nitrate nitrogen, denitrification ratio exceeding 90% in all rotating speed was obtained.5) At 60mg/L concentration of nitrate nitrogen, denitrification ratio in 120rpm of rotating speed was 90%. Moreover, denitrification ratio in 90rpm of rotating speed was 85%.U)High ratio of denitrification was obtained by controlling dissolved oxygen level to be under 1mg/L.

Removal of bacteria from seawater by foam separation using surface-active protein
Yoshihiro SUZUKI*, Nobuaki HANAGASAKI*, Terutoyo YOSHIDA**, Toshiroh MARUYAMA*
*:Dept. of Civil and Environmental Engineering, Miyazaki University, JAPAN
**:Dept. of Biological Production and Environmental Science, Miyazaki University, JAPAN
mSUZUKI Yoshihironsuzuki@civil.miyazaki-u.ac.jp
mHANAGASAKI Nobuakinnobuaki@civil.miyazaki-u.ac.jp
The removal of bacteria from rearing seawater of fish or using seawater in fishing port is important from the viewpoint of the reduction of infection risk and hygienics of public health.It is necessary to develop seawater purification technology for the improvement of hygienic conditions on the coastal environment.In this study,the removal of suspended bacteria Enterococcus faecalis from seawater by foam separation using several kinds of surface-active proteins as a chemical agent was examined.The removal effciency of enterococcus was extremely low by foam separation using each protein without coagulation,because these surface-active materials did not function as a collector.When processing by foam separation with coagulation as a pretreatment, however, proteins such as milk casein and fish mucus showed the greatest capability of suspended bacteria. For treatment of seawater containing enterococcus (107CFU/mL), the removal efficiency of counts number was over 99% with the small dosages of iron coagulant (FeCl3) 1mg-Fe/L and casein 1mg/L. Foam separation using surface-active protein with coagulation process has a high potential as a new method for removing bacteria from seawater.

Development of a Cost -effective Novel Sewage Treatment System by a combination of UASB Reactor and the gFourth Generationh Downflow Hanging Sponge (DHS) Reactor
Madan TANDUKAR*, Tsutomu OKUBO*, Takashi ONODERA*, Shigeki UEMURA**, Akiyoshi OHASHI* and Hideki HARADA*
*Dept. of Environmental Systems Engineering, Nagaoka University of Tech.
** Dept. of Civil Engineering, Kisarazu National College of Tech.
A long term experiment was carried out to evaluate the process performance of sewage treatment system consisting of UASB pre-treatment and the gFourth generation DHSh post-treatment unit. After the successful operation of second and third generation DHS reactors, the fourth generation DHS reactor was developed to overcome few shortcomings of its predecessors. This reactor was designed to further enhance the treatment efficiency and simplify the construction process in real scale, especially for application in developing countries. Configuration of the reactor was modified to enhance the dissolution of air into the wastewater and to avert the possible clogging of the reactor especially during sudden washout from UASB reactor. The whole system was operated at a total HRT of 8h (UASB: 6h & DHS: 2h) for a period of over 600 days. The combined system was able to remove 96% of unfiltered BOD with only 9 mg/L remaining in the final effluent. Likewise, F. coli were removed by 3.45 log with the final count of 103 to 104 MPN/100ml in the final effluent. Nutrient removal by the system was also satisfactory.

Treatment of Water-Based Metal Working Fluids Wastewater by Thermophilic Contact Oxidization Process and Influence of Carrier Water Content on the Degradation Efficiency
Xin FENG*CFutoshi KURISU**COsami YAGI**
*Environmental Engineering Course, Graduate School of EngineeringCUniversity of Tokyo,JAPAN **Research Center for Water Environment TechnologyCGraduate School of EngineeringCUniversity of Tokyo,JAPAN
[Xin FENG]hyousin@env.t.u-tokyo.ac.jp
Water-based metal working fluids wastewater contains complex and highly concentrated organic matters, some of which are resistant to the biodegradation. Thermophilic contact oxidation process (TCOP) is suitable for the treatment of high strength wastewater, and the thermophilic bacteria are known to be capable of degrading persistent chemical substances. Therefore, in this study we tested the application of TCOP for water-based metal working fluids wastewater and examined the influence of carrier water content on the treatment. Two kinds of compost for seeding almost equally supported the treatment of water-based metal working fluids wastewater by TCOP, and demonstrated TCOPfs capacity for the treatment. The oil reduction ratio was higher for lower carrier water content in the early stage of the experiment, but after 28 days of operation, the oil reduction ratio for all carrier water content reached almost same level, above 70%. The reduction of each component was also measured by GC/MS. In the early stage, the reduction ratios of fatty acids were higher for higher water content, and those of alkenes were higher for lower water content. These results suggested that the relationship between water contents and reduction ratios have a commonality among the same group of chemical compounds.

Development of a Novel Sewage Treatment Process for Minimum Energy Requirement - Treatment Characteristics of Sponge Carrier Trickling Filter as the Third Generation Type DHS Reactor -
Masanobu TAKAHASHI*, Takashi YAMAGUCHI*/**, Shigeki UEMURA***, Akiyoshi OHASHI****, Hideki HARADA****
*: Hiroshima Prefectural Institute of Industrial Science and Technology, Japan
**: Department of Civil Engineering, Kure National College of Technology, Japan
***: Department of Civil Engineering, Nagaoka National College of Technology, Japan
****: Department of Environment System Engineering, Nagaoka University of Technology, Japan
[Masanobu TAKAHASHI] masanobu@sankaken.gr.jp
[Takashi YAMAGUCHI] yamaguti@kure-nct.ac.jp
In the past several years our research group has been conducting R & D on a novel sewage treatment system applicable to developing countries by combination of an UASB anaerobic pretreatment unit and a DHS aerobic post-treatment unit. The DHS [downflow hanging sponge] process is our originally proposed concept, which employs poly-urethane sponge carrier as sludge supporting materials. In this study, the third-generation (G3-type) DHS reactor was installed at a municipal sewage treatment plant, and a long-term continuous experiment was conducted by feeding an actual sewage to the combined UASB/DHS system. The combined system achieved an excellent organic removal of over 90 % BOD, as well as nitrification of over 70 %, at HRT of 6hr for UASB and 2hr for DHS units, respectively. Some key factors governing superior performance of organic removal and nitrification were clarified by the continuous flow experiment. Due to no requirement of external aeration input and withdrawal of excess sludge, our combined UASB/DHS system would be definitely attractive option as less-energy required sewage treatment process, especially for developing countries.

A Study on VOC Removal in Tokyo Metropolitan University Wastewater Treatment Facility
*:Graduate School of Engineering, Tokyo Metropolitan University,Japan
Tokyo Metropolitan University constructed an advanced wastewater treatment facility when the university moved to its present location in 1991. To better serve the university, wastewater from experiments conducted by research laboratories was processed and recycled for flushwater. At the time, water quality guidelines for processed wastewater set by the university were more stringent than regulations established under the sewerage law. However, Volatile Organic Compounds (VOCs) were added to the sewerage law in 1994. As a result, it was necessary to revise the university's water quality guidelines and a directive was issued to collect VOCs directly from the research laboratories. Despite directly collecting VOCs, low levels of VOCs were still present in the wastewater and continued to flow into the wastewater treatment facility. Moreover, the past policy of annually replacing the activated carbon was not revised, creating a situation where VOC contaminant levels gradually rose until they exceeded the university's water quality guidelines.
This paper identifies removal characteristics of VOCs at the university's wastewater treatment facility and proposes a model to predict VOC levels in processed wastewater by using the facility's management data. This model can estimate, without performing actual tests on the activated carbon, an optimum replacement schedule.

Decomposition of Steel Process Wastewater Using Sulfate Reducing Bacteria and Denitrification Bacteria
*Graduate School of Natural Science & Technology, Kanazawa University,
** Nishihara@Environment@Technology, Inc.
Denitrification and sulfate reduction of phenolic wastewater were examined using anaerobic-oxic biological filter reactor. In the anaerobic reactor, sulfate reduction occurred. However phenol was not removed. In the anoxic reactor, heterotrophic denitrification and sulfur denitrification were occurred simultaneously. Phenol was utilized for denitrification. Utilization of cokes gas liquor wastewater by sulfate reduction and denitrificatin was examined using the biofilm in the reactor. Sulfate reduction occurred using ammonia stripped wastewater of the cokes gas liquor. However the phenol decomposition rates were very low. Heterotrophic denitrification occurred using the wastewater. Sulfur denitrification was not suppressed by the addition of the wastewater. Recovered sulfide from the gas liquor was utilized for sulfur denitrification.

Identification and quantification of sulfur-oxidizing bacteria in a newly developed sewage treatment system enhancing a sulfur-redox cycle action.
Shuji KAWAKAMI*, Nobuo ARAKI*, Takashi YAMAGUCHI**, Haruhiko SUMINO***,Shinichi YAMAZAKI**** and Naomichi NISHIO*****
* Dept. of Civil Engineering, Nagaoka National College of Technology
**Dept. of Civil Engineering, Kure National College of Technology
***Dept. of Civil Engineering, Gifu National College of Technology
****Dept. of Civil Engineering, Kochi National College of Technology
*****Dept. molecular biotechnology, Hiroshima university graduate school of advanced sciences of matter
[KAWKAMI Shuji] ac15828v@st.nagaoka-ct.ac.jp
[ARAKI, Nobuo] araki@nagaoka-ct.ac.jp
We have proposed a sewage treatment system by combining an anaerobic UASB and an aerobic biofilter reactor in order to diminish energy requirements and excess sludge production. A 17m3 pilot plant system was operated for over 300 days with continuous feeding of domestic raw sewage. The structure on microbial community of sludge samples taken from the aerobic biofilter reactor was analyzed by using clone libraries of 16S rRNA genes. Clone similar to Thiobacillus and Thiothrix was counted at 10 and 7, respectively, among 188 clones randomly selected from the libraries. Oligonucleotide probe Thio840 for fluorescence in situ hybridization (FISH) was newly designed for the specific target of Thiobacillus group. Approximately 7% of DAPI stained total cells in the biofilter sludge hybridized with the probe Thio840. This value was fairly agreed with frequency of the Thiobacillus clones to the libraries. Real-time PCR using SYBR green I was employed with BONE663cF-Thio840R primer set to determine the copy number of 16S rRNA gene originated from Thiobacillus. High concentration of sulfide at 30 mg-S/L in the influent strongly enhanced abundance of the gene of 105 copies/ng levels in total DNA extracted from the aerobic biofilter sludge. As a result, the real-time PCR assay could be an appropriate tool to monitor Thiobacillus cells in sludge. However, the difference of amplification efficiency between PCR standards and target genes is a subject of discussion.

Study on the Behavior of TOBr during Ozonation of Sewage Effluents
Hyo-sang KIM*, Harumi YAMADA*, Hiroshi TSUNO*
* Department of Urban and Environmental Engineering, Faculty of Engineering, Kyoto University
The formation characteristic of TOBr during ozonation of sewage effluents was investigated. Though TOBr increased rapidly in the initial stage, it decreased slowly after CT value was over about 20mgEmin/L. It was seen that absorbance at UV254 is a very available parameter for the estimation of TOBr formation.@TOBr in a secondary effluent was decomposed at extremely initial duration of ozonation. The result was confirmed by the increase of bromide concentration. The degradation and mineralization of organic compounds arise during ozone/hydrogen peroxide process. The addition of hydrogen peroxide also controls the formation of hypobromous acid and the dissolved ozone concentration. So, the amounts of bromate ion and TOBr formed can be controlled at low level.

Performance of Electrolytic Process for Water and Wastewater Treatment
*: Dept. of Civil and Environmental Engineering, Waseda Univ.
**: Ebara Corporation
[SAKAKIBARA Yutaka] sakaki@waseda.jp
Performance of a 3-dimensinal electrolytic process used for the treatment of dilute solutions was investigated in two different oxidation modes,i.e. direct oxidation on the surface of electrode and indirect oxidation through the formation of oxidant. Decolorization of indigotrisulfonate in these oxidation was measured and represented as an equivalent oxidation performance by O3. Experimental results demonstrated that electric current efficincy in the direct oxidation was 96% and energy consumption was significantly smaller than that of commercially-available ozonizer. However, the indirect oxidation process has poor performance in terms of electric current efficiency (1%) and energy consumption. It was considered that the direct oxidation process would be a feasible alternative of conventional oxidation process in water and wastewater treatment.

Development of removal method for ferric and manganese ions with fibrous graft-adsorbent
Manabu TAKAHASHI*, Kazuya TANAKA**, Masao TAMADA***, Toru AOI
*Advanced Environmental Eng. Course, Gunma College of Tech.
**Anzai co.,ltd.
***Department of Material Development, Takasaki Radiation Chemistry Research Establishment, Atomic Energy Research Institute
Fibrous metal adsorbent having iminodiacetic acid was synthesized by radiation-induced grafting glycidyl methacrylate on nonwoven fabric and subsequent chemical treatment. The degree of grafting calculated by increasing weight after grafting reached 170 % for reaction time of 2h at 40. The adsorption characteristics of ferric and manganese ions were evaluated by using the resulting adsorbent with 2.1 mmol/g-adsorbent function group of iminodiacetic acid. Each distribution coefficient of ferric and manganese ion deceased with increase of another coexist ion. Both ferric and manganese ions were completely removed by the adsorbent column at the space velocity of 1000h-1. Adsorption capacities of both ions were reduced to 80% after 5 times reputation of adsorption and desorption.

Development of the Simulation Model to Predict Dissolved Ozone Concentration for a Real Water Treatment Plant
Tadao MIZUNO, No-Suk PARK, Hiroshi TSUNO, and Taira HIDAKA
Department of Urban and Environmental Engineering, Graduate School of Engineering, Kyoto University
The simulation model to predict dissolved ozone concentration in a real ozone contactor was developed. The hydrodynamic behavior in the contactor was investigated by CFD (Computational Fluid Dynamics) technique before developing the reaction model. The ozone contactor was divided into small compartments and interaction between compartments was evaluated based on the result of CFD. Mass balance equations were established in each divided compartment with reaction terms. As state variables, organic compounds, odor compounds, bacteria groups, bromide ion, bromate ion as well as dissolved ozone were selected. Organic compounds were classified into only two groups in this model. The concentration of dissolved ozone was favorably evaluated and reasonable results were obtained for other items. From these, we conclude that dissolved ozone concentration as well as organic compounds, bacteria groups, bromate ion can be predicted in this model.

Effect of Organic Grafting Modification of Hexagonal Mesoporous Silicate on Haloacetic Acid Removal
Punyapalakul Patiparn*, TAKIZAWA Satoshi*
* Department of Urban Engineering, School of Engineering, The University of Tokyo
[Punyapalakul Patiparn] patiparn@env.t.u-tokyo.ac.jp
[TAKIZAWA Satoshi] takizawa@env.t.u-tokyo.ac.jp
Batch adsorption experiments were carried out using Hexagonal Mesoporous Silicates (HMSs) and dichloroacetic acid (DCAA) as a model Haloacetic acids (HAAs). The three types of grafted organic functional were n-octyldimethyl-, 3-aminopropyltriethoxy-, and 3-mercaptopropyl-groups. Titanium substituted HMS was also applied. Bi-functional grafted HMSs, which have both amino and mercapto functional groups, were synthesized to evaluate the effects of combined functional groups on adsorption capacities. Physical characteristic of synthesized HMSs didnft affect DCAA adsorption capacity; but grafted functional groups changed the surface charge of HMSs. Negatively charged DCAA was adsorbed only by positively charged HMS. A higher amount of surface amino-functional groups on HMS gave a higher positive surface charge and exhibited a higher adsorption capacity of DCAA. Combination of amino and mercapto-functional groups gave higher adsorption capacities in high DCAA concentration range despite lower surface charge than the amino-grafted HMS. Adsorption of DCAA decreased positive surface charge of HMSs due to neutralization of surface charge. At a low DCAA concentration range, adsorption capacities were strongly dependent on surface charge, and hence adsorbents with high positive charge densities, i.e. AM-HMS and A-HMS, had very high adsorption capacities for DCAA.

Irreversible membrane fouling caused by organic matters from different origins
Hiroshi YAMAMURA*, Katsuki KIMURA**, Yoshimasa WATANABE**
*-Master course student at Graduate School of Engineering, Hokkaido Uiversity
**-Graduate School of Engineering, Hokkaido University
[Yamamura Hiroshi] yamamura@eng.hokudai.ac.jp
[Kimura Katsuki] kkatsu@eng.hokudai.ac.jp
Membrane filtration has been gaining popularity in the various field. However, membrane fouling is an obstacle for wider application of this technology. Especially, the control of irreversible membrane fouling, which can be defined as fouling requiring chemical reagents to be mitigated, is of importance. The aims of this study were (i) to investigate the degree of irreversible fouling caused by different organic matters and (ii) to characterize the faulants that caused irreversible fouling. In this study, four different organic matters (commercially available humic acid, organic matters isolated from two drinking water sources and a wastewater treatment effluent) and membranes (two microfiltration (MF) membranes and two ultrafiltration (UF) membranes) were used. It was observed that the permeate flux did not decline in the UF membranes while there was a large flux decline in the MF membranes. Especially, a rapid flux decline was observed with the polyvinylidene fluoride (PVDF) membrane. The extents of fouling in the MF membranes were strongly depended on both the types of organic matters and membrane materials. A series of chemical analyses such as fluorescence excitation-emission matrix (EEM), specific UV adsorbance (SUVA) and ion chromatography (IC) were applied to elucidate which fractions of organic matter caused the irreversible fouling. SUVA of faulants was significantly lower than was determined for the feed water. This implies that the faulants had hydrophilic features. The results with EEM and IC also confirmed that a variety of hydrophilic compounds such as polysaccharide or protein-like compounds contributed to the formation of the irreversible fouling observed in this study.

Membrane fouling in membrane bioreactors for municipal wastewater treatment
Nobuhiro YAMATO, Katsuki KIMURA, Yoshimasa WATANABE
Depertment of urban and enviromental engineering, Hokkaido University
This study examined the influence of operating conditions on membrane fouling in membrane bioreactors (MBRs) used for municipal wastewater treatment. Also, the mechanism of fouling evolution was investigated based on both pilot-scale and lab-scale experiments. Three pilot-scale MBRs were operated for about 100 days at an existing municipal wastewater treatment facility. In the long-term operation, probably because aeration intensity was enough to avoid formation of cake layer on the membrane surface, reversible fouling was not significant (i.e., irreversible type of fouling dominated). The lab-scale experiments demonstrated that dissolved organic matter (DOM) accumulating in the reactors was likely to be responsible for the irreversible fouling. DOM loading on the membrane surface was found to influence the degree of total filtration resistance. It was revealed that changes in the composition of DOM (e.g., decrease in specific UV absorbance) in the reactors were also related to the irreversible fouling. Especially, dissolved sugar and dissolved protein contained in the mixed liquor played an important role in the development of the irreversible fouling.

Toxicity of Chlorinated Water in the Presence of Bromide Ion: Contribution of Brominated Disinfection By-Products to the Toxicity of Chlorinated Water
Shinya ECHIGO*, Sadahiko ITOH*, Toshiaki ARAKI**, Ryo ANDO*
*: Department of Urban Management, Graduate School of Engineering, Kyoto University, JAPAN
**: Murata Manufacturing Co., Ltd.
[Shinya Echigo]: echigo@urban.env.kyoto-u.ac.jp
Chromosomal aberration test and the differentiation method between total organic chlorine (TOCl) and total organic bromine (TOBr) were employed to evaluate the contribution of brominated disinfection by-products to the toxicity of chlorinated water in the presence of bromide ion. From the experiments using a high concentration humic acid solution, the toxicity of TOBr was found to be 4.8 times higher than that of TOCl on TOX basis, and the contribution of TOBr to activity inducing chromosomal aberrations reached 50% when the bromide-to-TOC ratio was 0.1 mg Br/mg C. Same experiments were conducted with Lake Biwa water. In this case, it was found that the toxicity of TOBr was found to be approximately 10 times higher than that of TOCl on TOX basis, and the contribution of TOBr to activity inducing chromosomal aberrations reached 30% even at the ambient bromide concentration (38.2 ?g/L).

Metabolism and microbial community of the phosphorus removing sludge using nitrite as electron acceptor
SHOJI Tadashi*, SATOH Hiroyasu**, MINO Takashi**
*:Department of Urban Engineering, Graduate School of Engineering, University of Tokyo, JAPAN
**:Institute of Environmental Studies, Graduate School of Frontier Sciences, University of Tokyo, JAPAN
[SHOJI Tadashi] shoji77@pwri.go.jp
[MINO Takashi] mino@k.u-tokyo.ac.jp
The effect of nitrite as electron acceptor was examined in a sequence batch reactor (SBR) for biological phosphorus removal. Experiments were carried out using a lab-scale SBR treating a municipal wastewater. The reactor had anaerobic phase followed by anoxic phase. To make anoxic phase, nitrate and nitrite were added. The phosphate uptake rate under both aerobic and anoxic conditions were measured by batch tests. Moreover, microbial communities were also analyzed using polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) assay. The following results were obtained from the batch test: 1) the sludge cultivated with nitrite could readily utilize oxygen as well as nitrite, 2) it could utilize nitrate after one hour adaptation, and 3) it could utilize nitrite to take up phosphate with same efficiency as nitrate or 40 % lower than oxygen. Furthermore, the DGGE image showed that a few bands appeared or disappeared when the operational condition changed. One possibility is that the changing bands were derived from denitrifying polyphosphate accumulating organisms (PAOs) either with nitrate or nitrite. Further research on these bands would clarify the behavior of the microbial community of PAOs.

Microbial Community Analysis by PDR-DGGE Method and In situ Identification of Bacteria in Enhanced Biological Phosphorus Removal Process Fed with Sole Carbon Sources
OKAMOTO Mayuko*, FUKUSHIMA Toshikazu**, ONUKI Motoharu***, MINO Takashi***
* Nishihara Environmental Technology, Inc.
** Sumitomo Chemical Co. Ltd.
*** Institute of Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo
[OKAMOTO, Mayuko] mayuko_okamoto@nishihara.co.jp
Due to a great progress in molecular techniques in microbial community analysis, microbes in enhanced biological phosphorus removal (EBPR) activated sludge are now intensively investigated. Several new candidates for polyphosphate accumulating organisms (PAOs) are now discovered or proposed. In this research, laboratory scale reactors were operated using glucose or aspartate as a sole carbon source and the microbial community was investigated using PCR-DGGE, cloning and FISH. In the aspartate fed reactor, Dechloromonas related bacteria which accumulated polyhydroxyalkanoate (PHA) but not polyphosphate (behaving like glycogen accumulating organisms (GAOs)) was found to exist significantly even when phosphate was well removed. On the other hand, in the glucose fed reactor, three Actinobacteria related genotypes were found. Although these genotypes were closely related to each other, one existed significantly when phosphate was removed well, and the others were found when the phosphorus removal activity was deteriorated.

Development of Quantification and Genotyping methods of Cryptosporidium in water by Quenching Probe PCR followed by RFLP
MASAGO Yoshifumi*, OGUMA Kumiko*, KATAYAMA Hiroyuki*, OHGAKI Shinichiro*
* Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo
[MASAGO Yoshifumi] masago@env.t.u-tokyo.ac.jp
A new method was developed to quantify Cryptosporidium in water. Quenching Probe PCR (QProbe-PCR) technique could successfully amplify approximately 1280bp of Cryptosporidium 18S rDNA from a sample with as low as 60 [oocysts/tube] of Cryptosporidium parvum bovine genotype. QProbe-PCR showed high accuracy and high sensitivity compared to Real Time PCR with TaqMan probe.
QProbe-PCR has an advantage that the PCR products can be applied for molecular characterization. A restriction fragment length polymorphism (RFLP) technique was used to distinguish Cryptosporidium species and genotypes. Five species (C. parvum bovine genotype, C. parvum human genotype, C. meleagridis, C. felis and C. muris) could be distinguished by the RFLP with restriction enzymes Ssp I, Vsp I and Sty I. The Sty I successfully differentiated C. muris calf genotype (also known as C. andersoni) and C. muris mouse genotype. Database-based analysis revealed that 8 species out of 10 could be distinguished by RFLP with these three restriction enzymes.
QProbe-PCR-RFLP techniques can provide information on the genotype as well as the quantity of Cryptosporidium from the same sample. This technique can be a useful tool for waterborne risk assessment of Cryptosporidiosis.

Population Dynamics of Nitrifying Bacteria in Biofilms Determined by Real-Time PCR
Tomonori KINDAICHI*, Yoshiko KAWANO**, Tsukasa ITO***, Satoshi OKABE***
*Dept. of Social and Environmental Eng., Graduate school of Eng., Hiroshima University
**Metocean Environment Inc.
***Dept. of Urban and Environmental Eng., Graduate school of Eng., Hokkaido Univ.
We investigated the population dynamics of nitrifying bacteria in autotrophic nitrifying biofilms by using Real-Time PCR and fluorescent in situ hybridization (FISH). Primers and TaqMan probe specific to genus Nitrospira including uncultured Nitrospira sp. in the biofilms were newly designed and applied to the biofilms. The populations of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) determined by Real-Time PCR during steady-state condition were 1.2~108 cells/cm2 and 3.5~108 cells/cm2, respectively. The population dynamics of nitrifying bacteria corresponded with the reactor performance and the development of nitrifying bacteria in the biofilms determined by FISH. Real-Time PCR revealed that specific growth rates of uncultured Nitrospira sp. were 0.021 h-1 in the suspended enrichment culture and 0.014 h-1 in the biofilms. Average specific growth rates of both nitrifying bacteria during the steady-state condition in the biofilms were significantly lower than that during the log phase, might suggest that metabolic pathway of nitrifying bacteria in the biofilms was different in the log and stationary phase. We speculated that Real-Time PCR was powerful and suitable technique for understanding of microbial population dynamics in the complex microbial communities.

Adenovirus-Binding Proteins (ADVBP) from activated sludge bacteria
Daisuke SANOCTeppei ISHIICTatsuo OMURA
Department of Civil Engineering, Graduate School of Engineering, Tohoku University
Outbreaks of waterborne infectious diseases caused by pathogenic viruses have been frequently documented over the world. Pathogenic viruses can survive for a long period in water environment, but there has been a difficulty in removing or inactivating viruses in conventional water and wastewater treatment systems. A new technology for the virus removal from water needs to be developed. In our previous study, virus-binding proteins (VBPs) demonstrating the ability to strongly bind Poliovirus type 1 (PV1) were recovered from a bacterial culture derived from activated sludge. It was expected that the isolated VBPs would be useful as viral adsorbents under the conditions of water and wastewater treatments. In order to develop new technology for virus removal, it is important to isolate not only VBPs for PV1 but also VBPs for other important pathogenic viruses in water. In this study, Adenovirus-Binding Proteins (ADVBPs) for Adenoviruses type 3 (AD3) and type 40/41 (AD40/41) were newly isolated from activated sludge culture with the affinity chromatography technique. Three distinct peaks were sequentially obtained in each affinity chromatographic profile of ADVBPs for AD3 and AD40/41, respectively. The isolated ADVBP in the first peak include a number of proteins, and their molecular weights were widely distributed. ELISA revealed that the ability of binding Adenoviral particle of ADVBP in the second and third peaks were stronger than those in the first peak in the affinity chromatographic profile. It is speculated that the isolated ADVBPs can be useful as specific adsorbents for Adenoviruses in several fields including virus removal, concentration and detection.

Construction of phage display for identification of algal proteins responsible for the inhibition of coagulation
SUZUKI takayoshi*, TAKAARA tomoko*, SANO daisuke*, OMURA tatsuo*
* Department of Civil Engineering, Graduate School of Engineering, Tohoku University
[SUZUKI takayoshi] suzuki@water.civil.tohoku.ac.jp
Seasonal overgrowth of cyanobacteria such as Microcystis aeruginosa (M. aeruginosa) is one of serious problems in semi-closed water area including reservoirs. It is known that algogenic organic matters (AOMs) bring about the inhibition of coagulation on the flocculation process in drinking water treatment systems. Our previous studies have shown that some kinds of protein in AOMs are responsible for the inhibition of coagulation, although the mechanisms of the inhibitory effects of algal proteins remain unclear. In order to reveal the inhibitory mechanism of algal proteins, it is necessary to identify the algal proteins closely related to the inhibition of coagulation. In this study, phage display using the genome of M. aeruginosa was constructed to extract algal proteins that exhibit the inhibitory effect on the coagulation. M. aeruginosa cells on steady growth phase were collected, and genomic DNA of M. aeruginosa cells was extracted. Then, extracted algal DNA was digested by the restriction enzyme Sau3AI. The phagemid vecter named pSKAN8-EWQ was newly created, in which BamHI recognition site was included as a single site for the restriction enzyme. Digested genomic DNA of M. aeruginosa was ligated with pSKAN8-EWQ, and the ligated phagemid vector was used to transform the competent cells of E.coli JM109. The cocktail of phages displaying algal proteins was obtained by introducing the helper-phage (VCSM13 Interference-Resistant Helper Phage) into the transformed E. coli cells. It was confirmed that obtained phages are able to infect E. coli. JM109, and transform E. coli. cells into the ampicilin-resistant strain. This thing indicated that the phage display system for algal proteins was successfully constructed. The phage display established in this study will definitely contribute to identifying the inhibitory algal proteins on the coagulation, and revealing the inhibitory mechanism in the further study.

The inner structure of nitrifying bacteria in biofilm fixed inside porous medium
Kosuke OSAKO*, Tomonori SUZUKI**, Hiroshi DEGUCHI***
*:Department of Civil Engineering, Graduate School of Science and Technology, Tokyo University of Science, JAPAN
**:Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, JAPAN
***:Department of Civil Engineering, Faculty of Science and Technology Tokyo University of Science, JAPAN
[Kosuke OSAKO] j7603701@ed.noda.tus.ac.jp
[Hiroshi DEGUCHI] hdegu@rs.noda.tus.ac.jp
The biomass fixed inside the porous medium, for example sponge cube, has the biofilm characteristics from the results of kinetic experiment. In this investigation, the biomass fixed inside the porous medium is nitrifying bacterium cultivated in autotrophic medium. Then characteristics of biomass fixed inside the porous medium was investigated by using Oxygen Utilization Rate (OUR). Furthermore the inner structure of nitrifying bacteria in biofilm fixed inside porous medium and biofilm thickness were investigated by Fluorescent In Situ Hybridization (FISH). Consequently The biofilm thickness by OUR was different from that by FISH.

Detection of Zostera marine habitat in Yamaguchi Bay
Shoichi OKABE**, Masahiko SEKINE*, Masao UKITA*, Tuyoshi IMAI*,Takaya HIGUCHI*,Kozi ASAI*, Hideki SATO**
*:Department of Civil Engineering, Yamaguchi University
**:Department of Civil Engineering, Master Course, Yamaguchi University
[Shouichi OKABE] a014fd@yamaguchi-u.ac.jp
Zostera bed is an important habitat for fish juveniles and other coastal living organisms. Thus, Zostera bed creation and/or remediation projects are operated in many places in Japan. When Zostera bed is created by planting seed, the environmental conditions need to be clearly understood for the region which may serve as Zostera bed. The purpose of this research is to determine the region which may serve as Zostera bed in Yamaguchi bay where Zostera bed remediation project is going on. By using bed conditions such as COD, IL, particle size, and the disturbance strength caused by wave and current, a HSC model was constructed to evaluate the Zostera bed habitat condition. Based on the bed condition HSCs, Zostera habitat might be spreading toward the north area of the present Zostera bed. By adding the disturbance HSCs, the north area of the present Zostera bed might be inappropriate, thus Zostera bed is limited in the present region.

Effect of metal hydrolytic products on the growth of attached algae
tsushi SASAKI*, Ayumi ITO**, Shinji TAKAHASHI*, Jiro AIZAWA* and Teruyuki UMITA*
*: Department of Civil and Environmental Engineering, Iwate University, Japan **: Graduate school of Frontier Materials and Functional Engineering, Iwate University, Japan
t5202005@iwate-u.ac.jp, aitou@iwate-u.ac.jp, umita@iwate-u.ac.jp,
The river Akagawa has been receiving the effluent from an acid mine drainage treatment plant. Intensive investigations were conducted to study the effect of the effluent on the growth of attached algae in the river Akagawa. From the results obtained by multivariate analyses of the data based on these intensive investigations, it was suggested that the metals in the sediments had an adverse effect on the growth of attached algae, and especially, Al in the sediments had the most adverse one. We carried out the investigation in the river Akagawa focusing on the Al forms classified into monomeric fraction (Al-a) and polymeric one (Al-b) by the ferrron method. The result showed that the middle reaches had a high concentration of Al-b containing phytotoxic Al13 polycation compared with the upper and lower reaches. In batch culture experiments of attached algae, it was found that an addition of Al to the culture accelerated the decay of algae severely in the pH range from 4 to 5. From these results, there is a possibility that the low content of Chlorophyll a in the sediment observed in the middle reaches of the river Akagawa is caused by Al-b formed by hydrolysis.

Development of the Coagulation Model for Humic Substances in Estuarine Condition
Akira SASAKI*, Manabu FUJII*, Toru WATANABE*, Tatsuo OMURA*
* Department of Civil Engineering, Graduate School of Engineering, Tohoku University
Humic substances (HS) derived from terristrial area play important roles to supply essential minerals for the growth of aquatic organisms in estuaries. Therefore, the watershed management focusing on the transportation of essential minerals from terrestrial area to estuaries is needed for the conservation of estuarine ecosystem. Although it is said that a part of HS coagulates in estuaries with the increase of salinity, its mechanism has not been well-known. In this study, the coagulation model for humic substances in estuaries was developed on the basis of DLVO theory and hydrophobolic interaction which caused a strong attractive force between HS. This attractive force was estimated with hydrophobic index (E254/TOC) of HS and its molecular weight detected by gel chromatography analysis with 254nm spectrophotometer. The developed model could explain the coagulation mechanism of humic acid according to the decrease of surface potential in estuarine condition. The result of simulation using this model showed that humic acid with intermediate molecular weight around 20kDa easily coagulated at the high salt concentration in estuaries.

Equilibrium and Coagulation Characteristics of Humic Iron Complex in Estuaries
FUJII Manabu*, SASAKI Akira*, WATANABE Toru*, OMURA Tatsuo*
*:Department of Civil Engineering, Graduate School of Engineering, Tohoku University
[FUJII Manabu] manabu@water.civil.tohoku.ac.jp
Humic iron complex is one of the most essential minerals for the growth of aquatic organisms in estuaries. However, the behavior of humic iron complex has not been known so well in estuaries where salinity widely changes. In this study, the effect of salinity on the behavior of humic iron complex was investigated with the Dando humic and fulvic acids. The increase of salinity, especially divalent cations such as magnesium and calcium ions, enhanced the coagulation of humic substances (HS). When the salt concentration increased from 0 to 30g/L, 81% of dissolved humic acid (HA) and 18% of dissolved fulvic acid (FA) transformed to the particulate (>0.45mm) due to the coagulation. Gel chromatography analysis with UV spectrometer (254nm) revealed that high molecular weight and hydrophobic fractions of humic substances were important factors relevant to the coagulation. The increase of salinity also enhanced the dissociation of iron from HA and FA. With the increase of salt concentration from 0 to 30g/L, 98% and 88% of iron dissociated from HA and FA, respectively. It was expected that amino and sulfo groups on the surface of HA and FA which possess a high affinity with iron contributed to the subsistence of dissolved iron in estuaries.

Establishment of the model for forecasting for the large amount death of Konosirus punctatus in Lake Shinji
ASADA Junsaku*, UNO Kazuo*, UEDA Tutomu*, SAKATA Tatuhiko**, IMAI Jun***
*:Department of Civil and Environmental Engineering, Matsue National College of Technology
**:Tottori Prefecture
***:Kyoto City
[ASADA Junsaku] asada@matsue-ct.ac.jp
[UNO Kazuo] uno@matsue-ct.ac.jp
Lake Shinji is the blackish lake, located in the east part of Shimane Prefecture. A large amount death of Gizzard shadiKonosirus punctatusjoccurred in 1996 in Lake Shinji. Since then, a strange phenomenon such as the death is making an appearance every year. This large amount death is a very serious problem for the fishery and the water quality environment in Lake Shinji.
This research, try to find causes of the death, describes a forecasting model that analyze the relation between the water quality and the large amount death of Gizzard shad. We considered about the hypothesis of the factor of Gizzard shad's death. Thinking about the hypothesis, we paid attention to decreased physical strength of Gizzard shad by the spawning. Additionally, we paid attention to Gizzard shad going up the river from Lake Nakaumi to Lake Shinji to spawn. And we will try to establish the model for forecasting the large amount of death based on the hypothesis.

Fundamental Study of the Growth Characteristics of the Phytoplankton in Miharu Dam Reservoir
Masahiro TEZUKA*,Youichi SATOU**, Yukihiko TAKAHASHI***, Michimasa NAKAMURA**
*:Graduate School of Engineering, Nihon University, JAPAN
**:College of Engineering, Nihon University, JAPAN
***:School of Municipal and Environmental Engineering Harbin Institute of Technology, CHINA
[Masahiro TEZUKA] sanita02@civil.ce.nihon-u.ac.jp
Abnormal growth of phytoplankton (water bloom) causes the impediments of water utilization. In Miharu Dam Reservoir, the water bloom did not grow in 2001, but it grew in 2002. Seasonal changes of the phytoplankton growth, water quality and weather condition in Miharu Dam Reservoir were investigated during 2001|2002. Growth characteristics of the phytoplankton in Miharu Dam Reservoir are examined from differences in 2001 and 2002.
Major results obtained from this study are;
i1j Conditions of the water temperature, daylight hours, and phosphorus were suitable for growth of the phytoplankton in 2002 rather than 2001.
i2j The difference of the phosphorus concentration of 2001 and 2002 is remarkable, and the difference is considered to have induced the difference of the phytoplankton growth.
i3j The phosphorus concentration of Miharu Dam Reservoir receives influence by the amount of the inflow phosphorus loads, and the amount of inflow phosphorus loads is restricted to the variation of flows accompanied by rain. Thus, it is considered that variation of the inflow phosphorus load accompanied by rain is the limiting factor of the phytoplankton in Miharu Dam Reservoir.

Study on the validity of a toxicity test using concentrated river water as an index of aquatic habitat condition in rivers
ODA Nozomu*, SEKINE Masahiko*, UKITA Masao*, IMAI Tsuyosi*, HIGUCHI Takaya*
*:Graduate School of Science and Engineering, Yamaguchi University
[ODA Nozomu] z016fd@yamaguchi-u.ac.jp
[SEKINE Masahiko] ms@civil.yamaguchi-u.ac.jp
A new toxicity test using concentrated river water and Medaka larva had been proposed by Urano et al. The purpose of this research is to clarify the relationship between this toxicity test and aquatic habitat conditions in rivers. Median Effect Time (ET50) and Median Lethal Time (LT50) are employed as indices of toxicity. ASPT (Average score per taxon) for benthic animals and IBI (Index of Biotic Integrity) for fish are applied as indices of aquatic habitat conditions. Although ASPT for benthic animals shows high correlation with toxicity, IBI for fish shows poor correlation with it. IBI consists of six elements, namely species richness, indicator species, immigrant species, fish condition, trophic composition and fish abundance. From multiple regression analysis of the IBI elements against the toxicity, the percentage of tolerant species, which is one of the IBI items, is verified having close relation with toxicity. From these analyses, it is revealed that two hours or shorter of LT50 and ET50 might cause deterioration of aquatic habitat.

Algal growth control with mud gels and silver-contained ceramics
Ryohei TAKANAMI*,Hiroaki OZAKI**,Shintarou HAYASHI**
Osamu YAMADA**,***,Tatsuo rUMINO****
*Dept. of Environmental Development Engineering, Graduate School of Engineering, Osaka Sangyo University, JAPAN
**FFaculty of Engineering, Osaka Sangyo University, JAPAN
***FOSU Co.,Ltd, JAPAN
****FHitachi Plant Engineering & Construction Co.,Ltd, JAPAN
[Ryohei TAKANAMI] s03dt01@sub.osaka-sandai.ac.jp
Algal bloom is one of the major environmental problems in closed water bodies. Reduced water currents and high inflow of nutrients to the water bodies are the main reasons behind this problem. Although many researches have been done, effective techniques to minimize the problem are still lacking. The objective of this investigation was to evaluate the effectiveness of mud gels and silver-contained ceramics in growth control of algal bloom. The experimental results showed that use of mud gels and silver-containing ceramics were very effective in controlling algal growth. Bacillus Megaterium was primarily affected while using mud gels. Photo catalysis and silver ions were mainly responsible for algal growth control while using silver-contained ceramics. Effectiveness of this technique increased when mud gels and silver-contained ceramics were used together probably due to synergic effects. This technique of controlling algal bloom can be more effective compared to other available methods.

Water Quality Analysis considering macrobenthos in Hakata Bay
KUMAGAI Hiroshi*, YAMASAKI Koreyoshi**, WATANABE Ryoichi**, FUiITA Kenichi***
*:Fukuoka Institute of Health and Environmental Sciences, JAPAN
**:Department of Civil Engineering, Fukuoka University, JAPAN
***:Kyushu Environmental Evaluation Association, JAPAN
[KUMAGAI Hiroshi] kumagai@fihes.pref.fukuoka.jp
[YAMASAKI Koreyoshi] yama@fukuoka-u.ac.jp
[WATANABE Ryoichi] wata@fukuoka-u.ac.jp
[FUiITA Kenichi] fujita@keea.or.jp
In this study we present a new ecosystem model which has a compartment of a macrobenthos Muscalista senhousia@which was mainly dominated in sediment at shallow water area of Hakata Bay. The results of water qualities estimated by this newly developed model were more precise than that estimated by a model which does not have the macrobenthos compartment. This result shows that macrobenthos in the sediment has a great effect on estimating the water concentrations and forecasting the behavior of oxygen-deficient water body.

Biodegradation and Biotransformation Pathways of 17-estradiol by Reservoir Sediment under Aerobic and Anaerobic Conditions
Fusheng LI*, Jun TSUMORI*, Naoyuki YAMASHITA*, Hiroaki TANAKA**, Yutaka SUZUKI*
* Water Quality Research Team, Public Works Research Institute, JAPAN
** Research Center for Environmental Quality Control, Kyoto University, JAPAN
Batch experiments using sediment mud liquors spiked with 17b-estradiol (E2) were performed at 5C and 20C under well-controlled aerobic and anaerobic conditions. The sediment mud liquors were prepared from the sliced surface, middle and bottom layers of sediment cores collected at a pre-reservoir of the Miharu Dam, respectively. By measuring the concentration profiles of E2 and its major biotransformation compound, estrone (E1), the great dependency of E2fs behavior upon the vertical position of the sediment and temperature was clearly demonstrated; and the differences in the time course of E1 under both the aerobic and anaerobic conditions were clearly revealed. Besides, by assuming a first-order rate reaction, the disappearance rate (k) of E2 under the aerobic condition was estimated to vary in the range of 0.002-0.12 (1/hr)/(g-dry/l), while that under the anaerobic condition in the range of 0.002-0.062 (1/hr)/(g-dry/l). Larger k values were found to be associated with the surface sediment layers operated under the aerobic condition and with the higher temperature of 20C. The addition of ammonia and nitrate to runs carried out under the aerobic and the anaerobic conditions, respectively, seemed to be responsible for promoted dissipation of E2 from solutions. Furthermore, through combined analysis of the behavior of E2 and E1 in both the liquid and the solid phases of the mud liquors, possible biotransformation pathways of E2 under both aerobic and anaerobic conditions were proposed.

Carbonation for immobilization of lead in bottom ash
Akifumi MOTOHATA*, Jungjoon LEE*, Ruina ZHANG*, Shogo SAKITA**, and Takayuki SHIMAOKA**
* Department of Urban and Environmental Engineering, Graduate School,
Kyushu University, Japan
**Department of Civil Engineering, Graduate School of Engineering, Kyushu University, Japan
[Akifumi MOTOHATA] motohata@ies.kyushu-u.ac.jp
[Takayuki SHIMAOKA] shimaoka@ies.kyushu-u.ac.jp
Utilization of municipal solid waste (MSW) incineration residue as construction material is discussed due to the lack of the capacity of MSW landfill site. And, it is required that heavy metal components such as Pb in bottom ash has not to leach out. In this study, the immobilization of Pb by carbonation process was examined as a pretreatment for the stabilization of heavy metal components in bottom ash. It was confirmed that Pb concentration of leachate from bottom ash greatly decreased by CO2 gas passing through the bottom ash packed in column. Especially, water content range from 10 to 20 % in bottom ash was suitable for the absorption of CO2 gas and Pb immobilization. Changes of alkalinity and EC that affect immobilization of Pb by CO2 gas were observed. Increases of calcite(CaCO3), which is able to adsorb Pb were also confirmed with X-ray diffraction analyses. Mechanism of immobilization of Pb was examined by using the chemical equilibrium computation of various Pb spicies.

Settlement and flocculation characteristics of incineration residue in sea area landfill site
Daisaburo Koga, Takayuki Shimaoka, Shogo Sakita, Takeomi Yokoo and Hiroshi Kokubo
*Department of Urban and Environmental Engineering, Graduate School, Kyushu University
**Department of Civil Engineering, Graduate School of Engineering, Kyushu University
***Penta-Ocean Construction Co., Ltd.
This paper focuses on the characteristics of settlement and flocculation of incineration residue in sea area landfill site. The column was filled with seawater and bottom ash which was put into the column. The seawater for analyses was vertically and intermittently sampled, while sedimentation situation of particles in the seawater was observed. Bottom ash that settled in the seawater was separated into fine-grained and coarse-grained waste; and it became clear that once it threw into seawater the fine-grained waste layer (mud layer) piles up over the coarse-grained waste layer (coarse-grained layer). Fine-particle waste contains twice as many components of organic as coarse-grained waste. Furthermore, coefficient of permeability of mud layer was order of 10-6 cm/s. It is possible that mud layer prevented diffusion of the pollution component from coarse-grained layer to the seawater. The pollution component in landfill will be decreased, if there are flocs in the settlement. This means that by the promotion of flocculation and its active clearing, and that the stabilization of a sea area landfill site is promoted.

Heavy metals leaching behavior of carbonated cement solidified fly ash from incineration facilities and melting facilities
Yutaka Dote*, Tomoo Sekito* and Daisuke Nawata**
*:Department of civil and environmental engineering, University of Miyazaki, JAPAN
**Fukken CO.,LTD), JAPAN
[DOTE yutaka] dote@civil.miyazaki-u.ac.jp
[SEKITO tomoo] sekito@civil.miyazaki-u.ac.jp
MSW fly ash generated from MSW incineration facilities and melting facilities has to be stabilized or solidified by solidification / stabilization treatment before landfilling because of a high leachability of hazardous heavy metals. Although cement solidification is used as a typical method for fly ash treatment, addition of cement causes an increase in the amount of landfill waste due to cement volume. In this study, carbonation treatment as pre-treatment of cement solidification treatment was applied to fly ash obtained from 4 incineration facilities and 8 melting facilities (gasification - melting facilities and ash melting facilities). Leaching tests were performed by JLT 13 and Pb, Cd, and Cr concentrations were determined.
Concentration of Pb in lechate from carbonated fly ash were decreased. This result implies that the carbonation would be an effective treatment for reduction of the amount of cement added to fly ash for stabilization of heavy metals. However, Pb concentrations from some carbonated fly ash samples obtained from gasification - melting facilities were not below the Japanese regulatory criterion for hazardous industrial wastes landfilling even 30% of cement was added to the fly ash. From XRD analysis, for carbonated fly ash from which Pb concentration of leachate was lowered to the criterion successfully, it was found that slow carbonation would be effective for the preventing of Pb leaching. Concentration of Cd in leachate from some melting fly ash increased according to decrease of pH by carbonation, however, the concentration could be lowered by 10% of cement addition and alkalinity such as calcium hydroxide to maintain high pH.

Behavior of Nonylphenol ethoxylate in natural water environment -the case of Barato Lake-
HIGASHI Ryuji*,FUKAZAWA Tatsuya*,KUDO Kenzo*,TATIBANA Harukuni*, SHIMIZU Tatsuo*
*Department of Environment and Resource Engineering, Faculty of Engineering, Graduate School, Hokkaido University, Japan
A sampling campaign for the determination of concentrations of nonylphenol ehoxylates (NPnEO) and those persistent metabolites in freshwaters and sediments of sewage treatment plants (STPs), rivers, and lake in Sapporo. Water samples were collected from eighteen sampling sites in STPs, rivers, and lake (from November 2003 to December 2003), while sediment samples were collected from three sampling sites in lake (Febrary 2003). And based on the survey, risk to wildlife in water environment and behavior of nonylphenol ethoxylates and those metabolites were discussed. In this study, shorter-chain nonylphenol ethoxylates, nonylphenol carboxylates (NPnEC), and nonylphenol (NP) were analyzed as metabolites of NPnEO. But according to recent study, there are other metabolites (for example, CAPECs, both ethoxy side chain and alkyl side chain are carboxylated). Concentration of NPnEO metabolites in the STP effluent was 9% of influent. 91% was removed or degraded to metabolites that couldfnt be analyzed in this study. Concentrations of metabolites that could be analyzed in this study in Barato Lake was under LOEC (Lowest Observed Effective Concentration), and the compounds were proved to be harmless to wildlife there.Concentrations of each depth of lake sediment reflected the reduction of domestic production quantity of AP.

Occurrence of Polycyclic Aromatic Hydrocarbons (PAHs) in Lake Sediment and Sedimentation of PAHs with Particle Matter at River Mouth
MINAMIYAMA Mizuhiko*, SUZUKI Yutaka**
* : Recycling Research Team, Public Works Research Institute (present: Wastewater and Sludge Management Division, Water Quality Control Department, National Institute for Land and Infrastructure Management)
** : Recycling Research Team, Public Works Research Institute (present: Water Quality Research Team, Public Works Research Institute)
[MINAMIYAMA] minamiya@pwri.go.jp
Environmental pollution caused by hazardous organic substances has become a problem. The hazardous organic compounds that exist in the watershed concentrate in closed water bodies via rivers. In particular, several papers have reported on the pollution of bottom sediment of closed water bodies with polycyclic aromatic hydrocarbons (PAHs). We are investigating to clarify the status of pollution and fate of sediment with PAHs. In this study, it was revealed that the concentrations of PAHs in the sediment near the river mouth were high because of their sedimentation with particle matter. It was also revealed that we could control the PAHs from the river using an artificial lagoon constructed near the river mouth.

Study of Time Series Analysis on Riverbed Sediments in Tama River Estuary
*:Graduate School of Engineering, Tokyo Metropolitan University,Japan
**:Tokyo Metropolitan Research Institute for Environmental Protection
This paper examines the impact of the growth of sewered population in the Tama River watershed and its impact on the bottom sediment of the Tama River estuary. Vertical core samples for sediment quality analysis were collected from five locations from the Tama River estuary toward the center region of Tokyo Bay. Each core was cut into 2.5`5 cm sections. Grain size, volatile solids, and nonyl phenol levels were measured from core sections and data were obtained revealing changes in the vertical and horizontal directions of the sediments. The relationship between sediment quality and the percentage of sewered population is analyzed and the results indicate levels of nonyl phenol in the sediment decreases as the percentage of sewered population increases. This analysis also provides a new model for calculating sediment settling velocity.

Quantification of Dioxins in the Sieved Fraction of River Sediment
Shogo TANIGUCHI*, Norihumi SHIMOMUKAI**, Naoya OKUDA**,Ryohei TAKANAMI**,Hiroaki OZAKI***, Tastuhide HAMASAKI****, Masataka SUGAHARA****
* : High-Tech Research Center, Osaka Sangyo University
** : Graduate School of Engineering, Osaka Sangyo University
*** : Dept. of Civil Engineering, Osaka Sangyo University
**** : Dept. of Urban Environment, Osaka Sangyo University
[Shogo Taniguchi] taniguch@cnt.osaka-sandai.ac.jp
Dioxin pollution of aquatic sediments has been one of the important environmental problems in Japan.Grain size distribution and organic constituents may play important roles in dioxin contents in sediments, which have not been well investigated. This paper aimed to quantify dioxins(PCDDs/Fs and co-PCBs) in sieved surface sediment fractions obtained from Kizu and Sumiyoshi River in Osaka, Japan. The samples were prepared and analyzed following gthe Manual of the Survey and Measurement of Dioxins in Sedimenth (Environment Agency in Japan, 2000) and gMethod for determination of tetra- through octa- chlorodibenzo-p-dioxins, tetra- through octa-chlorodibenzofutans and coplanar polychlorobiphenyls in industrial water and wastewaterh (Japanese Standards Association, 1999) The results showed that TEQ concentrations of dioxins increased with increasing the contents of Ignition Loss (IL) in the sediment fractions. Thus, reporting dioxin contents in sediments without considering grain size distribution may be erroneous, and conventional sediments. This information can be useful for effective remediation of dioxin-contaminated sediments.

Sludge disintegration treatment by the simultaneous use of ultrasonic and electrochemical processes
WATANABE Tomohide*, ZENG Dao-Yong**, CHO Kyung-Jin* and KURODA Masao*
*: Department of Civil Engineering, Gunma University, Japan
**: Department of Production Engineering, Graduate School of Engineering, Gunma University, Japan
[WATANABE Tomohide] watanabe@ce.gunma-u.ac.jp
A novel disintegration treatment of the activated sludge by the simultaneous use of ultrasonic and electrochemical processes was investigated experimentally. Two reactors equipped with or without an electrolytic diaphragm to divide into the anodic and cathodic compartments were irradiated with ultrasound. The batch disintegration experiments were carried out at different conditions of the ultrasonic frequency, the applied electric current to the electrodes and the initial sludge concentrations. Alkaline and acidic conditions developed in the cathodic and anodic regions of the reactors, respectively, when the electric current was applied even at relatively low electric power. The electrochemically generated alkaline condition and the ultrasonic irradiation synergistically facilitated the activated sludge solubilization, comparing with the sonication alone, whereas, the appearance of acidic condition in the anodic region had no acceleration effect. The acceleration effect of solubilization depended on the applied electric current. The ultrasonic irradiation of higher frequency was ineffective for the sludge disintegration in the simultaneous processes, suggesting that the sonoelectrochemical disruption of bacterial cells was not predominant. In this investigation, the simultaneous use of the ultrasonic and electrochemical reaction processes could achieve the effective sludge solubilization without any chemical doses.

The Effects of Coexisting Substances on Rejection of Endocrine Disrupting Chemicals by Low Pressure Reverse Osmosis Membrane
Norihito IKEJIMA*, Hiroaki OZAKI**, Saburo MATSUI*, Ryohei TAKANAMI****, Shogo TANIGUCHI*****, Mutsuhisa KOUTO****
*:Graduate School of Global Environmental Studies, Kyoto Univ., Japan
**:Dept. of Civil Eng. Osaka Sangyo Univ., Japan
***:Graduate School of Global Environmental Studies, Kyoto Univ., Japan
****:Graduate School of Osaka Sangyo Univ., Japan
***** HRC, Osaka Sangyo Univ., Japan
[Norihito IKEJIMA] nori@eden.env.ktoyo-u.ac.jp
This study aimed to investigate the effects of coexisting substances on separation of endocrine disrupting chemicals (EDCs) in water and domestic wastewater effluents using low pressure reverse osmosis (LPRO) membrane. The coexisting substances included calcium chloride, glutamic acid sodium salt, acetic acid and humic substances whose molecular weight ranged up to twenty thousand. The results showed higher rejection of nonylphenol in a mixed solution of the coexisting substances. Thus, the results indicated that coexisting substances can affect rejection properties of EDCs in LPRO membranes. In using higher desalting membranes, much higher rejection rates of EDCs in domestic wastewater effluents were observed compared to rejection of a single solution, which shows over 95% rejection. However, rejection of E2 from domestic wastewater did not increase with relatively loose membrane.


Fluctuation of influent organic components of municipal wastewater treatment plants and its impact on ASM simulation
*:Research and Technology Development Division, Japan Sewage Works Agency
[ITOKAWA Hiroki] itokawah@jswa.go.jp
[MURAKAMI Takao] murakamit@jswa.go.jp
Influent COD components defined in ASM (SA, SF, SI, XS, XH, and XI) were monitored at municipal WWTPs with three different time intervals. In addition, impact of observed influent fluctuation on ASM simulation was estimated by sensitivity analysis of each COD component, and by simulation study with various influent data preparation. Each component showed diurnal, daily, and long-term fluctuation, in terms of both concentration and fraction of total COD. SS (SA + SF) showed the largest fluctuation, which was comparable to the previously observed SS variation among 12 municipal WWTPs. A good correlation was shown between influent SS and VFAs, although filtered COD analysis gave significant higher SS estimation compared to respirometric method. XS estimation from long-term BOD measurement compared well to that with respirometric method. According to the sensitivity analysis, influent SA or XS could have significant influence on simulation results within a range of observed fluctuation, especially for biological phosphorus removal. Steady state simulation with daily average influent characteristics gave a practically same output as dynamic simulation, showing the validity of model calibration with steady state data, although influent fractionation data not representing daily average state could cause inappropriate calibration/simulation.

A study in the vertical distribution of soil contamination with heavy metals in residential districts
Osamu BANNAI*, Tatsuya TANIKOSHI**, Takashi TSUJI***, Minoru YONEDA****, Shinsuke MORISAWA****
*Doctor Course Student at Graduate School of Engineering, Kyoto University
**TOYOTA Motor Corporation
***Master Course Student at Graduate School of Engineering, Kyoto University
****Graduate School of Engineering, Kyoto University
[Osamu BANNAI] bannai@risk.env.kyoto-u.ac.jp
Heavy metals exist in soils by nature and are accumulated in soils caused by fallout. It is difficult to identify the amount of soil contamination because fallout was not so heavy compared with natural existence. In this study, soils are divided into two fractions: (upper 0-2.5 centimeters and lower 2.5-5.0 centimeters depth) in order to measure the concentration except the background concentration. As a result of comparing two-layer partitions, arsenic and cadmium are accumulated at the lower layer with the form extracted with nitric acid. Park soils may have been polluted with lead by fallout because the lead is much accumulated in the upper soils than the lower soil.



Relation between arsenic and other metals and ions in groundwater in Bangladesh
Koichi OHNO*, Akihiko FURUKAWA*, Kenji HAYASHI*, Tasuku KAMEI*, Yasumoto MAGARA*
* Dept. of Urban and Environ. Eng., Graduate School of Eng., Hokkaido University, Japan
The periodic survey of shallow tubewells had been conducted in Nawabganj municipality, Bangladesh. During the survey, water samples had been collected 6 times and the concentrations of arsenic and other substances including metals and ions were analysed. As a result of the survey, not only arsenic but also iron, manganese and uranium concentrations in groundwater exceeded WHOfs Drinking-Water Quality Guideline Value. As for seasonal variation, concentrations of arsenic and iron seemed to be higher in the rainy season, but it was not obvious. In terms of the correlation between arsenic and other substances, manganese (r= 0.37), molybdenum (0.33) and sulfate ion (-0.33) correlated with arsenic. When the cases with arsenic above 1mg/L were removed, iron (positively) and chloride ion (negatively) correlated with arsenic in addition to the 3 substances mentioned above. Finally, it is suggested that there should be two patterns of arsenic elution into groundwater. One is the elution under reducing condition and it is mainly seen in the lower arsenic range below 0.2mg/L. Correlation between arsenic and iron can be seen in this case. The other is the arsenic elution without the presence of iron, and it is mainly seen in higher arsenic range, especially above 1.0mg/L.

Control of Run-Off of Nitrate-Nitrogen to the River from the Agricultural Area in Central Hokkaido, Japan
Koichi YAMAMOTO* and Harukuni TACHIBANA**
*National Institute for Land and Infrastructure Management, Ministry of Land and Transport
**Graduate School of Engineering, Hokkaido University
[KOICHI YAMAMOTO] yammer@k2.dion.ne.jp
[HARUKUNI TACHIBANA] harukuni@eng.hokudai.ac.jp
Nitrate concentration in the river water in farmland basin tends to be higher than in forested basin. We assumed that the source of high concentration of nitrate in the river water was aerobic groundwater which is contaminated by NO3--N. We applied the End-Members-Mixing-Analysis (EMMA) to calculate the contribution of aerobic groundwater. To use EMMA, we selected Alkalinity (4.3Bx) and nitrate as tracers. We estimated that the nitrate concentration in aerobic groundwater by land use, nitrogen load to the ground, and hydrological parameters. Increase of the area of the farmland will raise the nitrate concentration in the aerobic groundwater and river water. Effect of increasing grassland area will be smaller than that of farmland. Excess manure in the basin also raise the nitrate concentration in the aerobic groundwater, and it was clarified that application of the excess manure to the grassland reduced the contamination compared to the case of discarding manure to the bare land.

* Department of Ecological Engineering, Toyohashi University of Technology, JAPAN
[G.A ANGGARA KASIH] anggara@earth.eco.tut.ac.jp
[Toshihiro KITADA] kitada@earth.eco.tut.ac.jp
On many marine systems, nutrient has been identified as the pollutant of concern, and is believed to stimulate the excessive alga growth. In this study, eutrophication model was used to clarify the factors regulating the chlorophyll-a production in Mikawa Bay. We have examined the temporal variations of total nitrogen (TN), chlorophyll-a, and bay water temperature as well as those of input river flow rate and tidal height for two months from May to early Juli in 1998, during which algal bloom events occured.The obtained results are as follows: (1) near at the bottom in the inner bay, TN concentration started to increase after 1 May due to enhanced TN release from the sediment, which followed by chlorophyll-a, (2) TN and chlorophyll-a near the surface layer were strongly affected by river flow rate; the TN concentration showed its sharp increase when the river flow rate increased, and in contrast the chlorophyll-a was decreased; they were because of high TN and low chlorophyll-a concentrations in the river water, (3) the high chlorophyll-a concentration at the event was caused by combination of the high TN input through increased river flow rate before the event and the subsequent weak ventilation of the inner bay water under the neap tide condition, and (4) the weak ventilation was further enhanced by strong stable stratification in the inner bay.

Continuous monitoring of water quality in supplying high concentration dissolved oxygen water into hypolimnion of a dam reservoir
Jun TSUMORI*C Hiroaki TANAKA**C Yutaka SUZUKI*C Jianhua Li***C Junnosuke WADA****C Katsutomo TANAKA***** and Shinji FUKUI******
*: Water Quality Research Team, Public Works Research Institute, Japan
**: Research Center for Environmental Quality Control, Kyoto Univ., Japan
***: College of Environmental Science and Engineering, Tongji Univ. China
****: Environmental Research Div., Sanyo Techno Marine, Inc., Japan
*****: Environmental System Sales Div., Yokogawa Electric Corp., Japan
******:6 Environmental Project Div., Matsue Doken, Inc., Japan
[TSUMORI Jun] tsumori@pwri.go.jp
Nutrient release from sediments sometimes significantly affects water quality of eutrophicated reservoirs. Various studies have been conducted so far on countermeasures for controlling nutrient release from the sediments by supplying oxygen gas into water such as Micro bubbles system and Injection of surface water into bottom layer in reservoirs. In this study, we investigated a novel water quality restoration technology supplying water supersaturated dissolved oxygen into the bottom layer to control nutrient release from the sediments. We had conducted a field investigation in Ushikubiri reservoir using the technology from July 23 to September 15, 2002. Temperature, DO and ORP in water column were continuously monitored at two locations by a sensor system during the experimental period. Further, we observed nutrients, Chl-a, SS, VSS and DOC concentrations in water column by manual samplings. The DO supply system was intermittently operated by temperature control, in order to maintain stratification of the water column even under DO supply. As a result, increase in DO in the bottom layer was significantly observed without destruction of the stratification, which resulted in decrease of phosphorus and nitrogen concentrations in the water column. The decrease in total nitrogen in the middle layer of the water column seemed due to denitrification because of depletion of DO in the middle layer. This field experiments demonstrates that the system could reduce nutrient release from the sediments and improve water quality of water column.

Tsuyoshi IMAI*, Masao UKITA*, Masahiko SEKINE* and Takaya HIGUCHI*
* Department of Civil and Environmental Eng., Faculty of Engineering, Yamaguchi University
In this study, the method of using high concentrated oxygen water to depurate the bottom sediment was confirmed to be effective. The high concentrated oxygen dissolver was developed and the lab scale experiments were performed. High rate, high efficiency oxygen dissolver was developed, the optimum running condition of the equipment and the method of making high concentrated oxygen water was discussed in this study. In addition, the repression of phosphorus release by high concentrated oxygen water was also studied. On the basis of the fundamental knowledge from the lab scale study, pilot scale apparatus was set up and the pilot study was carried out.

Effects of year-round warmer condition to the growth and phenology of Cryptomeria japonica
Masanori YAMAMOTO*, Atsushi NAKASHIMA**, Aki OKUDA**, Hisanori OKUDA***, Tatsuya KUSHIDA****
* : Graduate School of Systems Engineering Wakayama University
** : Faculty of Systems Engineering Wakayama University
*** : RECREATION AND TOURISM BUREAU GREENERY Promotion Division Parks Construction Department
**** : The Institute of Medical Science, The University of Tokyo
[Masanori YAMAMOTO] s044060@sys.wakayama-u.ac.jp
This study aimed to examine that the effects of year-round warmer conditions to the growth and the phenology of two-year-old Cryptomeria japonica seedlings. The growth and the phenology of C. japonica were investigated grown under several controlled temperature conditions of outdoor temperatures altered by }0.0, +1.0, +2.0, +3.0. The results indicated that, the growth period were longer under warmer conditions, because growth halt were later and the spring flush were earlier under warmer conditions. Though the spring flush were earlier under warmer conditions, cumulative temperature from growth halt to the spring flush were increased under warmer conditions. Main shoot elongation, the speed of main shoot elongation, and length of between branches were greater under +2.0 and +3.0 treatments. Number of branches was increased under warmer conditions. Male flowers were not formed under }0.0 treatment, but they were formed under warmer conditions. The blooming period began late under warmer conditions.

Improvement of the BCR sequential extraction procedure for the elution characteristics of chromium from cement
Yoshinori KANJO, Hiroaki SAIKA, Takatomi SHIMA
*Graduate school of engineering, Osaka City University
[Yoshinori KANJO] kanjo@urban.eng.osaka-cu.ac.jp
[Hiroaki SAIKA] saika@me.civil.eng.osaka-cu.ac.jp
[Takatomi SHIMA] shima@me.civil.eng.osaka-cu.ac.jp
The BCR sequential extraction procedure has frequently been used to the distribution of metals for sediments. In this paper, we improved this procedure in order to obtain the elution characteristics of chromium from cement which shows high alkalinity. As the results, we proposed the new modified BCR sequential procedure added with the neutralization by acetic acid. In addition, we determined the chromium distribution in several kinds of cements by this new procedure.

Evaluation of Grain Paroduction by using EPIC model and Study of Food Security in the Weihe Basin
Baba Keisuke*,Tetsuya Kusuda**,XiaochangCWang***,Dawwen Yang****, Osamu Higashi*****,Shinpei Ozaki*,Katsufumi Shibata*
*Department of Urban Environmental Engineering,Faculty of Engineering,Graduate School,Kyushu University,
**Department of Urban Environmental Engineering,Kyushu University,
***School of Environmental & Municipal Engineering Xifan University of Architecture & Technology,
****,Department of Hydraulic Engineering Tsinghua University,
*****Japan Science and Technology Agency
In China, the concern with agricultural problems, such as decrease in farmland and in products, has been growing due to accedein WTO and the national policy.Erosion-Productivity Impact Calculator(EPIC) has been widely used to analyze the relationship between soil erosion and agricultural porductivity. It has the ability to simulate yields for various crops in field, and each crop has specified values for the model parameters. In this paper, the annual crop yield (1992-2001) is simulated and the food security in the Weihe Basin is evaluated. It was found from the results that there is considerable validity in the simulation results by use of this model's and they are useful for the food security in this basin.

Estimation of origin of tunnel seepage by environmental isotopes and river flow rate
Daisuke GOTO*CHiroyuki II**CTatemasa HIRATA**,Takanari YOSHIKUNI***,Yasunori OTSUKA***,Masatoshi KANAGAWA****
*:Graduate School of Systems Engineering, Wakayama University
**:Department of Systems Engineering, Wakayama University
***:Oyo Corporation
****:Hyogo Toyooka public works office
[Hiroyuki II] hiro@sys.wakayama-u.ac.jp
The origin of tunnel seepage water was determined to be the catchment of mountainous area beside the tunnel by environmental oxygen and hydrogen isotopic data of tunnel seepage water, river water, snow and rain water and flow rate. As stable oxygen and hydrogen isotopic data of precipitation depended on altitude, comparing isotopic data between tunnel seepage water and river, snow and rain water of catchment, tunnel seepage indicating low D and 18O values was estimated to originate from high altitude area. River discharges of catchments near the tunnel were various and low value catchment was thought to be groundwater source area to tunnel seepage water. The both low discharge area and low D and18O value area were coincided to be mountainous catchments within 3km.The areas have a lot of snow in winter and can supply a lot of water to tunnel.

Control of Nitrogen Leaching from Agricultural Soil Columns using Microorganisms Supporting Medium and Inoculation of Activated Sludge
*:Graduate School of Natural Science & Technology, Kanazawa University
[TAKANO Morihiro] tknmrhr@stu.kanazawa-u.ac.jp
[YAMAMOTO-IKEMOTO Ryoko] rikemoto@t.kanazawa-u.ac.jp
Control of nitrogen leaching from the agricultural field is examined using the soil columns in the intermittent rainfall conditions. Nitrification and denitrification occurred in the soil columns. Inoculation of activated sludge in the lower part of soil columns was not effective to control of nitrogen leaching. When supporting medium made up of foamed polypropylene was packed and activated sludge was inoculated in the lower layer of soil columns, the concentration of nitrogen significantly decreased. The activities of sulfur denitrification and sulfate reduction in the soil over the supported medium layer increased. Sulfur oxidation-reduction cycle played an important role in the control of nitrogen leaching.

Research on present state of nitrate-nitrogen pollution and the source of Omama alluvial fan ground water
Koji IWATA, Tatsuyuki SAITO, Toru AOI, Tomio OTSUKA
*Advanced Environmental Eng. Course, Gunma College of Tech
**Department of Civil Engineering, Gunma University
Many individual supply wells in the Town of Nitta, located on the edge of Omama alluvial fan, have been analyzed to make clear the contamination degree of NOx-N and Coliform group. The Omama alluvial fan which is located on the southern foot of Mt. Akagi is a representative alluvial fan made by the ancient Watarase river. On the alluvial fan region, the cultivation of fresh vegetables and pulses, the breeding of beef cattle & pig and dairy are very popular.
In the 123 shallow well water quality examination, only 12 samples satisfied the drinking water regulation (<10mgN/l), but 112 samples exceeded the reference value, and 56 samples exceeded that of the confirm group(non-detective). Then the geological investigation and land use investigation was carried out in order to clarify the derivation of the high nitrogen concentration.

Development and Evaluation of a Mathematical model for the Urban Area's water pollution in the Weihe Basin
Osamu Higashi*,Tetsuya Kusuda**, Xiaochang Wang***, Dawen Yang**** Kazuhisa Inoue*****,Shinpei Ozaki******,Katsuhumi Shibata******
*:Japan Science and Technology Agency,
**:Department of Urban Environmental Engineering, Kyushu University,
***:School of Environmental & Municipal Engineering Xi'an University of Architecture & Technology,
****:Department of Hydraulic Engineering, Tsinghua University,
*****:Department of Urban Environmental Engineering, Faculty of Engineering, Graduate School, Kyushu University
The Weihe river basin which is the greatest tributary in the Yellow river, is one of the base areas for the Western Region Development in China. In recent years, its water demand has been increasing drastically due to rapid industrial development and population growth. Wastewater treatment plants, however, have not established enough yet, so that the wastewater treatment ratio in this area is only 20% and BOD of water in the river is always over 100mg/l near urban areas in dry season. In this study, the authors investigate water utilization, such as irrigation and reservoir control, drainage system and pollutant load fluxes in the Weihe basin, by analyzing GIS data and satellite images, then, develop a water quantity and quality integrated model, and evaluate water balance, river water quality, based on field surveys and GBHM2 (geomorphology-based hydrological model 2 (Yang et al.,2002)). In conclusion, the wastewater treatment ratio should increase at least 80% to meet the China surface water standards.

Oligotrophy in a lot of litter accumulated pond and river under reductive condition
Eiji MUROGA*CHiroyuki II**CAtushi NAKASHIMA**
*:Graduate School of Systems Engineering, Wakayama University
**:Department of Systems Engineering, Wakayama University
[Hiroyuki II] hiro@sys.wakayama-u.ac.jp
Some river and pond in Kagawa prefecture were oligotrophy although a lot of litter was accumulated in the pond and river, lack of nitrate and concentration of Fe ion was very high in both river and pond. In particular, Fe ion in the bottom of the pond reached 10-3 mol /l with low Eh values and SO42- concentration decreased. The bottom of the pond has a lot of litter and consumed oxygen through decomposition process of organic compound. Under light reductive condition, NO3- was thought to change into N2 gas by denitrification with organic compound and then, under medium reductive condition, Fe oxide was thought to change into Fe ion with organic compound. In particular, in the litter at the bottom of pond, some SO42- was thought to change into H2S gas or HS-. Therefore, a lot of litter is necessary to keep oligotrophic condition.