Laboratory-scale sequencing batch reator (SBR) activated sludge processes were operated using synthetic wastewater to investigate the effects of disturbance (e.g. from anaerobic/aerobic operation to aerobic operation or decrease in the influent etc.) on the population dynamics of bio-P-bacteria in activated sludge ecosystems.
From this research, it is clarified that Q-9 was predominant ubiquinone in activated sludge showing high phosphorus removal ability. The responces of phosphorus removal ability and quinone profile suggested that the deterioration and the slow recovery were dependent not only on the decrease in the activity of each bio-P-bacteria but on the decrease in their population, i.e. species succession of bacteria.
The isolated strain of Pseudomonas was identified to be a bio-P-bacteria for accumulated polyphosphates as well as the strain of Acinetobacter in activated sludge ecosystems. It is suggested that the isolated strains of Acinetobacter and Pseudomonas, which contained major quinone of Q-9, played an important role in phosphorus removal in activated sludge processes.

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For the purpose of reducing the anaerobic fluidized-bed reactor start-up period by increasing the initial biomass concentration, the operational conditions and mechanism of the pelletizing seed sludge were investigated by using laboratory- and bench-scale equipments.
It has been revealed that the factors that affect the pelletization process are the concentration of the recycled sludge, the upflow rate of the sludge recycle in the reactor and the distribution of the carrier material diameter. In addition, it has been found that the pellets (2 to 5 mm in diameter) can be formed within several tens of hours by limiting these factors within an appropriate range. During the pelletization process, the needle-shaped matter was first formed with the sludge adhering in a broom shape to the upper side of each carrier, and then they were merged and rolled while incorporating the recycled sludge. The pelletization process took place physically rather than by biomass growth.
The initial biomass concentration in the reactor could be made to be 4,000 to 8,000 mg VSS·l^-1, due to pellet formation.

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The relationships between organic loading rate 3.5-8.75 kgTOC·m^-3·d^-1, granulation property and treatment efficiency were studied through about 600 day operation in a laboratory-scale UASB reactor at a normal temperature (20°C). The results obtained from this study were as follows : (1) In case of organic loading rate 3.5-7.0 kgTOC·m^-3·d^-1, maintenance of the shape of globular glanule, the increase in the median granule diameter, the increase in the ratio of white and grey granules and the increase in the bulk density of granules were obseved. After 600 days of reactor operation under these conditions, granulation property was maintained and about 87% TOC reduction was achieved ; (2) In case of organic loading rate more than 7.0 kgTOC·m^-3·d^-1, the shape of granule changed to on irregular type, and disintegrated at 8.75 kgTOC·m^-3·d^-1, the bulk density of granules were changed lighter, TOC reduction was reduced quickly.
It was made clear that the organic loading rate was a significant factor for maintenance of optimum granulation and treatment property.

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A method was developed for the simultaneous analysis of organophosphorus pesticides including acephate in water.
A water sample was shaken with 20% hexane in dichloromethane. Then anhydrous sodium sulfate was added in the sample to dehydrate until the water layer disappeared. The organic layer containing pesticides was collected, evaporated and then dissolved in acetone. The extract was determined by gas chromatography. Thirteen kinds of pesticides were separated by using capillary column TC-1701, and linearities of calibration curves of them were satisfactory. Recoveries of pesticides added to water samples were from 93.6% to 106.2% except dichlorvos (from 52.3% to 79.9%) and ethylthiometon (from 64.4% to 84.3%).

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A test plant and a wastewater treatment system for a practical and biological treatment of lipid containing wastewater were installed at a Meat Plant in the Sendai district of Japan. In these systems, the raw wastewater was primarily treated in the cultivation tank where a lipid-assimilating bacterium was inoculated. The mixture of the wastewater, bacterial cells and air was taken at the surface of the tank and transported to the bottom of the tank. The wastewater was subsequently treated by activated sludge process as usual.
The test plant was very effective in removing lipid of the wastewater which contained relatively hibh concentration of lipid. When the whole contents of the cultivation tank were transferred to an aeration tank, the digestion of lipid, and the decreases in COD and BOD were further observed. A practical cultivation tank was installed at a prior step to the aeration tank which existed in the Meat Plant. COD and BOD of effluent were lower than 35 and 10mg·l^-1, respectively. These values cleared the effluent standard.
From these results mentioned above, it was confirmed that lipid-containing wastewater could be treated by this system without using a physical treatment.

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