김원만 Won Man Kim

DOI: Vol.2(No.1) 1001-1012, 1986

The seasonal and spatial fluctuation of petroleum-degrading bacterial population was wstimated in the coastal water near Soch`on-gun. The number of petroleum-degrading bateria measured in the range of 3.0 × 10^1 cells/1 - 7.5 × 10^2 cells/1 with a relatively small population. The proportions of the number of petroleum-degrading bacteria to total viable counts were in the range of 0.031% - 0.000064%. Pseudomonas, Enterobacteriaceae, Aeromonas, Vibrio, Acinetobacter and Staphylococcus were isolated as petroleum-degrader. To examine correlations for petroleum-degrading bacteria and other environmental factors, correlation coefficients were obtained. Highly significant correlations were observed between petroleum-degrading bacterial number and total viable counts and also shown between the number of petroleum-degrading bacteria and biochemical oxygen demand.

양병수 , 진현국 , 정형숙 Byung Soo Yang , Hyun Gook Jin , Hyung Sook Chung

DOI: Vol.2(No.1) 1013-1025, 1986

The effects of short-and long-term temperature change on organic removal rate and gas production rate were evaluated with the treating the synthetic wastewater composed of glucose and non-fat dry milk in an up flow floating anaerobic digester. Some results from this study are summarized as the followings. During the period referred to as a steady-state condition in an up flow floating anaerobic digester due to the fact that the relative changes in both COD removal rate and gas production rate are sufficiently small, biological solids continually accumulated as operating time elapsed. The activity of the accumulated biological solids could offset a decrease in organic removal rate and gas production rate because of temperature drop. These results imply that high organic removal efficiency can be obtained at even relatively low operating temperature when large biological solids is maintained in digesters. The composition of the produced biogas was nearly not changed during the short-term temperature drop and gas production resumed at the same rate as soon as the temperature restored to initial level. The effects of short-term temperature drop on attached growth anaerobes are not so significant as that on suspended growth anaerobes. It seemed to be because of the difference in biomass in digesters.

최용진 , 류재근 , 송준상 , 서윤수 Yong Jin Choi , Jae Keun Ryu , Jun Sang Song , Yoon Soo Suh

DOI: Vol.2(No.1) 1026-1034, 1986

A bacterium capable of uitilizing 2, 4-dichlorophenoxyacetic acid (2, 4-D) as a sole source of carbon and energy was isolated from soil samples of farm lands by using a chemostatic culture method. Taxonomic characterization demonstrated the isolate the be a species of Pseudomonas. An actively growing culture of the strain, designated CS-90 was able to degrade more than 98% of 2, 4-D at 500 ㎎/ℓwithing 3 days and more than 94% of 2, 4-D at 2,000 ㎎/ℓwithin 6 days. The strain was also found to be able to utilize other aromatic compounds such as benzoate, salicylate as its sole source of carbon, and oxidize chlorinated organic compounds, especially chlorinated phenolic compounds. Resting cells of CS-90 could dechlorinate 2, 4-D and release 97% of chloride ion at 500 ㎎/ℓof substrate in phosphate buffer by incubating at 30℃ for 24 hours.

이갑상 , 민경석 , 김남대 Kap Sang Lee , Kyung Sok Min , Nam Dae Kim

DOI: Vol.2(No.1) 1035-1042, 1986

Optimal culture conditions of wild Chl. ellipsoidea for tapioca alcohol distillation waste treatment were examined, and results obtained were as follows: For wild Chl. ellipsoidea culture organic medium was more effective than inorganic one. Optimal dilution for alcohol distillation waste treatment was three times. Optimal culture conditions were 6.0 of pH, 30℃ of temp., 8-10 Kilolux of light intensity, 1.0% of glucose, 0.2% of urea, 0.4% of KH₂PO₄ and 0.02% of MgSO₄-7H₂O concentration. Glucose should be added for three times diluted alcohol distillation waste treatment. BOD removal efficiency of alcohol distillation waste by Chl. ellipsoidea was 91% when inoculated of seed cultured in waste liquid and 87% when inoculated of seed cultured in waste liquid culture solution.

박동욱 , 이홍근 Dong Wook Park , Hong Keun Lee

DOI: Vol.2(No.1) 1043-1054, 1986

This study was carried our to investigate the properties of thermal stratification, algal productivity, and the vertical distribution of dissolved nutrients and chlorophyll-a at Three stations of right bank in DAECHUNG Lake during the period from June to August, 1985, for the purpose of finding out the primary productivity of phytoplankton while summer stratification occurs. The following results were obtained: The stratification were showed obviously by difference of dissolved oxygen concentration water temperature, the average concentration of dissolved oxygen at hypolimnion layer was 5.7mg/1. The a average concentration of gross production at epilimnion layer was 0.70 O_2 mg/1/day in June, 0.97 O_2 mg/1/day in July, 1.30 O_2 mg/1/day in Aug, which was abruptly decreased at thermo cline layer. The average concentration of total phosphorous at hypolimnion layer was 0.059 mg/1 in June, 0.044 mg/1 in July, 0.321 mg/1 in Aug., which was over Vollenweider`s eutrophic standard 0.04 mg/1. The average amount of chlorophyll-a at epilimnion layer was 9.9 mg/m^3 in June, 6.3 mg/m^3 July, 23.9 mg/m^3 in Aug. It is guessed that the growth level of phytoplankton was large. A highly significant correlation was found between total phosphorous and chlorophyll-a at the epilimnion layer (r = 0.85 p : 0.01). Therefore it could be confirmed that phosphorous was the limiting factor to algal growth.

이윤석 , 안승구 Yun Seok Yi , Seung Koo Ahn

DOI: Vol.2(No.1) 1055-1063, 1986

Models of the autothermal thermophilic aerobic digestion process for stabilization and pasteurization of sewage sludge were proposed. They can be applied to the continuous and semi-continuous operations in completely stirred tank reactor. Oxygen concentration term was added to the first order reaction kinetic to investigate the influence of the oxygen concentration on the reaction rate. Sludge was considered as a nonnewtonian (pseudoplastic) fluid. For the effective operation of the process the sludge concentration must be high and the thermal protection of the reactor with isolation material should be required. The RPM of turbine impeller and the air supply velocity must be selected on the basis not only of the organic removal rate but also of the efficiency; quantity of the removal organics per unit energy input. Also the semi-continuous operation appears one of the most effective process for the stabilization and pasteurization of the sludge.

안태석 , 안태영 , 권오섭 , 조기성 Tae Seok Ahn , Tae Young Ahn , Oh Seob Kwon , Ki Seong Joh

DOI: Vol.2(No.1) 1064-1070, 1986

The concentrations of phosphate-P, ammonia + amino acid-N, nitrite-N, and nitrate-N were measured at 4 sites in the polluted Masan Bay from 1978 to 1982. The mean concentration of phosphate-P, ammonia + amino acid-N, nitrite-N and nitrate-N in each site varied 0.68-1.90 ㎍ at-P/ℓ, 1.21-4.36 ㎍ at-N/ℓ, 0.36-3.23 ㎍ at-N/ℓ and 2.17-29.45 ㎍ at-N/ℓ, respectively. At site 1 and 2, nearby Masan City, the concentration of nitrogen was gradually increasing according to the increase of the population of the city and the N/P ratios at site 1 and 2 reached more than 40.

Jung Hyun Kim , 영목기지 Motoyuki Susuki , 강전광정 Mitsumasa Okada

DOI: Vol.2(No.1) 1071-1078, 1986

To assess the fecal contamination, the coprostanol was measured by GC-MS in Chung Ryang stream from November 3, 1985 to May 25, 1986, which was much polluted by municipal sewage and night soil from the crowd residential area, a part of Seoul, along the stream. That was compared with the coliform group and was analyzed statistically. The result was obtain as follows ; The coprostanols were determined at 0.6-1.5 ng/1 in the range of concentrations. The concentrations were not significantly different from the up-stream to the down-stream. The numbers of coliform groups were gradually increased as lower the streams. It was shown in no relationships between the coprostanol and tee number of coliform groups in the stream(r = 0.18). With the above results, it is discussed that the coprostanol is not reliable in the determination of fecal contamination as an index of water qualities.