In order to improve nitrogen removal efficiency, an anaerobic filter-aerobic biological filtration process was modified by filling. with nitrifying bacteria immobilized carrier made of polyethylene-alcohol (immobilized pellets) as a media for biological filtration tank. The effect of water temperature on T-N removal efficiency was investigated.
When aeration was performed so that the immobilized pellets were fluidized above the ceramic carrier filled in the biological filtration tank, T-N was successfully removed. T-N removal efficiency was increased by increasing the filled ratio of immobilized pellets by replacing a portion of the ceramic carrier at the water temperature of 10°C. Conversely, the removal efficiency was lower when the filled ratio of immobilized pellets was 60%, due to the increase of suspended solids in the effluent. Therefore, a proper filled ratio of immobilized pellets was thought to be about 50%.
The nitrification rate at the water temperature of 5°C was 17 mg·l^-1·h^-1 for the immobilized pellets and 3.9 mg·l^-1·h^-1 for the ceramic carrier, thus the nitrification rate of the former was 4.4 times that of the latter. Removal rates of the inflow carbon and nitrogen were 72% as carbon dioxide and 65% as nitrogen gas, respectively.

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Eight strains of filamentous fungi, which were known as producers of amylase and glucoamylase for digesting raw starch, were used for investigating treatment capacity of the synthetic cassava starch processing (SCSP) wastewater containing pure cassava starch. Among these strains, three strains of Aspergillus oryzae showed high efficiency in the removal of COD and TOC, starch hydrolysis and production of fungal biomass. With A. oryzae KCC F-0010, treatment efficiency obtained 72% (TOC), 81% (COD), 94% (starch) and 2.4 g/l of biomass after 14-day incubation. The presence of cyanide caused inhibition for the growth of fungi. The toleration of A. oryzae IFO 30113 to cyanide was associated with its ability to remove cyanide. Ammonia was indicated as the end product of biodegradation of cyanide. Volatilization and microbial metabolism were shown as the main mechanisms in the cyanide removal of the aerobic treatment process by fungi under the acidic condition.

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Acomparative study of construction and function of microfauna (protozoa and metazoa) communities in biological domestic wastewater treatment reactors with and without a microorganism activator (Saponin) was carried out. It was showed that the addition of Saponin did not change the construction of microfauna communities, but promoted the growth of microfauna, especially attached rotifer that was famous as useful metazoa in biological treatments. The variation of species of metazoa was smaller than that of protozoa. When water temperatures dropped in the range of 10-13°C, the growth of protozoa highly decreased, but the growth of metazoa increased, showed that metazoa was highly tolerant to low temperatures than protozoa. The biomass of a special group of microfauna with the habits of attached living and SS feeding in the reactor with Saponin was the highest in microfauna communities and remarkably higher than that in the reactor without Saponin. Moreover, rotifer Philodina sp. was the most prosperous in all species of that special group. Statistical analysis showed the close connection between biomass of attached microfauna with the habit of suspended particle feeding and effluent SS concentrations, indicating these microfauna played an important and useful role in the removal of suspended solids.

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Treatment of sewage sludge by composting for the production of materials useful as a soil amendment is a feasible method of achieving both waste disposal and agricultural enhancement simultaneously. However, the hygienic safety of the final products is an issue which requires resolution. This study was an investigation of the effects of heating patterns on the inactivation and regrowth potential of Salmonella, Escherichia coli, and Faecal streptococcus. A laboratory thermal controller was used to apply three patterns of heating; namely, single-impact, constant, and intermittent. Single-impact heating showed the greatest effect on inactivation and intermittent heating had the least effect.Also, the organisms subjected to single-impact heating had the least regrowth potential while those subjected to intermittent heating had the greatest potential. The addition of inorganic suspended solids (kaolin) and dissolved organic matter severely inhibited the inactivation of all the organisms.

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Sediment monitoring device using ultrasound was constructed. Location data of the monitoring position was identified by coupling with global positioning system. It was found that ultrasound at 40 kHz frequency was optimum for scanning the lake and bay sediments layer. Comparison between scanning results using ultrasound and chemical analysis revealed that there is a correlation between organic matter contents in the soil and scanning data.

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Application of anaerobic treatment to the biodegradation of reactive dyes using sucrose as a co-substrate was evaluated for five Sumifix Supra dyes (Blue; Scarlet; Navy; Red and Yellow) in batch and continuous-flow UASB assays. Results of the batch tests showed that with an initial TOC concentration of 500 mg/l high dye removal efficiencies of 97% and 98.6%were obtained for the Sumifix Supra Blue and Yellow, respectively, after 24 hours of incubation. It was shown that increasing sucrose concentrations enhanced the mte of dye reduction. At an initial TOC concentration of 1500mg/l the slowly decolourizing Sumifix Supra Scarlet, Navy and Red dyes were effectively decolourized with dye removal efficiencies of 91.7, 95.6 and 97.3%, respectively. The decolouization processes of all the examined dyes proceeded without a lag phase and followed first-order kinetics. Results obtained from continuous-flow UASB treatment showed that a sludge concentration of about 16 g-VSS/l was most effective, at which high TOC and dye removal efficiencies of greater than 95% and 82%, respectively, were obtained. Results of this study provide further insight into the combined treatment of sugar and dye industrial wastewaters using an UASB process.

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A new filamentous Bacillus strain, Bacillus funiculus NAF001 (JCM 11201^T=CIP 107128^T) isolated from activated sludge was found to utilize sodium dodecyl sulfate (SDS) up to a concentration of 0.5% (dissolved SDS concentration 0.40%) . At this concentration 20% of the dissolved substrate was degraded within 5 days. At 0.2% substrate concentration (actual concentration 0.10%) 60% of the substrate could be degraded. Utilization of SDS was concomitant with cell growth indicating that SDS is utilized as the source of carbon. Though there were many earlier reports on SDS degradation, they all were by members of Pseudomonas or related species. Strain NAF001 was found to be the first strain among Bacillus spp. which degraded SDS.

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