• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.339-344
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• 2000

Utilization of animal excreta in aquaculture can have potentials of high fish production and low maintenance costs for fish farming and it can reduce water pollution caused by animal waste disposal. Integration of wastewater treatment pond system with aquaculture has been utilized in many countries. Ecologically balanced pond ecosystem is formed through the stabilization of wastes, the growth of aquatic plants, and the cultivation of fish. The most appropriate fish for rearing in these ponds are those which can feed directly on phytoplankton, especially algae. Carp were introduced into a tertiary pond - water depth of 2.2 m, water surface area of $130\;m^2$, volume of $148\;m^3$ - of a pond system treating milk cow excreta. The carp production was $125g{\cdot}m^{-2}year^{-1}$ which falls into upper range of $18\;-\;137g{\cdot}m^{-2}year^{-1}$ of treated sewage-fed carp farming of other countries. Average $BOD_5$ and T-N of the pond was 19.8 and $21.0\;mg{\cdot}L^{-1}$ respectively, and the ecological environment of it was suitable for growth of carp. Several carp of 100g were introduced in August into a secondary pond of the treatment system, whose average $BOD_5$ and T-N was 27.9 and $30.8\;mg{\cdot}L^{-1}$ respectively. They were died within one week, which may be attributed to the depletion of dissolved oxygen at dawn. Effluents from primary treatment can be used in fish pond with dilution and those from secondary treatment can be directly funnelled into it. Waste stabilization pond treating animal excreta can be utilized for fish rearing when its water quality maintains secondary treatment level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.140-145
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• 2002

The performances of a parallel current air driven type foam separator were evaluated in the pilot-scale recirculating aquaculture system. The system was stocked with Nile tilapia (Oreochromis niloticus) at an initial rearing densities of $2\%$, $5\%$ and $7\%$ of water volume of rearing tank and reared for 15, 30, 35 days, respectively. The condensated volume of effluent foam was increasing with increased rearing density. As increasing rearing density from $2\%$ to $7\%$, the protein concentration in rearing tank was increased from 16.6 g/$m^3$ to 21,9 g/$m^3$ and the removal amount of protein through foam separator as increased from 0.99 g/day to 2.5 g/day. But protein concentration ratio in the foam was decreased from 3.2 to 1.9. Changes of the removal amount and the concentration ratios of total suspended solid (TSS) and chemical oxygen demand (COD_cr.) were similar to proteins. The highest concentration ratios of TSS and COD_cr. were 10.2 and 8.4 at 2$2\%$ of rearing density.

• Journal of Korean Society of Water and Wastewater
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• v.9 no.2
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• pp.108-117
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• 1995

The applicability to Korea is examined of a pond system which treats and recycles wastewaters. Air temperature and solar radiation of the pond systems at Corinne, Utah, and Eudora, Kansas, which are located in temperate regions of the U.S., are compared with those of Kimpo lying in the mid-western part of Korea. Analyzed are also $BOD_5$ and SS concentrations, algal concentrations, pH levels, and water temperature of the two systems. Air temperature of Kimpo is quite similar to that of the two systems, and solar radiation of Kimpo is more conducive than that of the systems to the growth of algae during summer. Analysis of $BOD_5$ and SS concentrations in the final effluent of the systems shows that they meet the secondary treatment standards. The study demonstrates that wastewater treatment pond system which is similar in design to the systems can be reliably utilized at Kimpo, Korea. A model is proposed which can integrate a pond system with aquaculture and agriculture.

• Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.373-378
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• 2015

Postprandial ammonia excretion and oxygen consumption in olive flounder Paralichthys olivaceus fed two different feed types, moist pellet (MP) and expanded pellet (EP) diets, to satiation were determined at $12^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$ for 48 h. The ammonia excretion and oxygen consumption rates increased with increasing water temperature. However, the postprandial times for the maximum rates of ammonia excretion and oxygen consumption were shortened from 12 h to 6 h after feeding with increasing water temperature. The ammonia excretion and oxygen consumption rates of the fish fed EP were significantly higher (P < 0.05) than those fed MP at 12 h post-feeding both for $12^{\circ}C$ and $15^{\circ}C$. The highest (P < 0.05) weight-specific ammonia excretion rates at $12^{\circ}C$ were observed in the fish fed EP and MP at $12.1mg\;NH_3-N\;kg^{-1}h^{-1}$ and $8.7mg\;NH_3-N\;kg^{-1}h^{-1}$, respectively, for 12 h and 9 h after feeding. The highest (P < 0.05) weight-specific oxygen consumption rates at $12^{\circ}C$ were observed in fish fed EP and MP at $116.4mg\;kg^{-1}h^{-1}$ and $101.0mg\;kg^{-1}h^{-1}$, respectively, for 12 h after feeding. The highest ammonia excretion rates at $25^{\circ}C$ in the fish fed EP and MP increased to $16.9mg\;NH_3-N\;kg^{-1}h^{-1}$ and $18.3mg\;NH_3-N\;kg^{-1}h^{-1}$, respectively, for 6 h after feeding. The highest (P < 0.05) weight-specific oxygen consumption rates at $25^{\circ}C$ were observed in fish fed EP and MP at $184.3mg\;O_2kg^{-1}h^{-1}$ and $197.3mg\;O_2kg^{-1}h^{-1}$, respectively. These data are valuable for the design of biofilters and development of effluent treatment technologies for the land-based flounder farms.

• Journal of Aquaculture
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• v.12 no.1
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• pp.47-56
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• 1999

Denitrification by anaerobic bacteria is one of the most common processes of removing nitrate from recirculating aquaculture systems. This process is affected by many factors such as external carbon sources, hydraulic retention time (HRT), and $COD/NO_3-N$ ratio. Although external organic carbon sources are essential for the denitrification process, these also contribute to increase dissolved organic carbon concentration in recirculating aquaculture systems. So these external organic carbons must be removed from the systems. This study was conducted to find out the optimum operating conditions for the removal of external organic carbons in a submerged denitrification biofilter. Combinations of two external carbon sources (glucose and methanol), two HRT (4- and 8-hour), and four different C:N ratios (3, 4, 5, and 6) were used in this experiment. The removal efficiencies of organic carbon sources at 8-hour HRT were always better than those at 4-hour's (P<0.05). Maximum removal efficiencies were achieved when C:N ratio was 5 in both glucose and methanol. The removal efficiencies of methanol were always better than those of glucose. The maximum removal efficiencies of glucose and methanol were 76.5% and 84.0%, respectively and the removal rates were 223.5 $g/m^2/day$ and 247.1$g/m^2/day$. The maximum removal rates of glucose (290.9 $g/m^2/day$) and methanol (355.6 $g/m^2/day$) were achieved at 4-hour HRT and 5 C:N ratio. But the concentrations of SCOD in the effluent of both glucose ($52.5 mg/\ell$) and methanol ($40.9 mg/\ell$) were too high for rearing fish. Therefore, the optimum operating conditions for the removal of external carbon in a submerged denitrification biofilter were 8-hour HRT and 5 C:N ratio. And methanol showed better efficiency as an external carbon sources.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.100-100
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• 2003

양식 산업에 있어 사육 생물의 빠른 성장은 가장 요구되는 특성이다. 특히, 선발육종을 통한 성장 개선은 사료의 효율적 이용과 연관되어 있으며, 균형 잡힌 단백질 대사 등을 통해 이루어진다. 대부분의 경골어류는 단백질 대사의 마지막 부산물로 암모니아를 생성하여 배설하며, 이를 통한 사료 내 단백질의 효율적 이용성을 비교하는 척도로 제시되어 왔다(Ming, 1985). 따라서 본 실험에서는 한국해양연구원에서 선발육종 해 온 참돔과 일본 양식산 참돔 및 이들의 교배 자손들을 대상으로 일간 먹이 공급, 절식 그리고 1회 만복 공급에 따른 암모니아성 질소 배설률을 조사하였으며, 일간 먹이 공급에 따른 각 교배 자손들의 분 배출 특성을 알아보았다. 실험어는 일본 양식산인 JPN 교배구 자손과 한국해양연구원 선발육종산인 KORDI F4 교배구 자손, 그리고 JPN$\times$KORDI F4♂ 교배구 자손을 대상으로 실시하였다. 체중이 각각 17.1$\pm$0.1 g (JPN 교배구; 그룹 1), 17.7$\pm$0.1 g (JPN♀$\times$KORDI F4♂; 그룹 2), 21.5$\pm$0.1 g (KORDI F4; 그룹 3)인 참돔 치어를 각각 15마리씩 3반복 수용하여 실험에 이용하였다. 실험어는 지름이 33 cm이고 높이가 34 cm인 둥근 투명 플라스틱 수조에 수용하고 분 수집기인 TUF column (passing effluent water through a special test tube) system을 이용 어체중의 3%에 해당하는 사료 량을 일간 세 번에 나누어 동일량을, 09시부터 17시까지 4시간 간격으로 공급한 14일째에 일간 먹이 공급에 따른 24시간 동안의 참돔 종간 잡종 치어의 총암모니아성 질소(total ammonia nitrogen, TAN) 배설률 및 분 배출률을 조사하였다. 이 조사가 끝난 후 3일간 절식시킨 다음 내인성 암모니아성 질소 배설을 조사하였으며, 이어서 1회 만복 사료 공급한 다음 이에 따른 암모니아성 질소 배설 경향을 알아보았다. 일간 먹이 공급에 따른 각 실험구의 암모니아 배설은 세 가지 계통 참돔치어 모두 먹이 섭취 후 암모니아 배설로 인한 TAN 농도가 지속적으로 증가하는 경향을 보였으며, 시간당 TAN 배설률을 적분한 결과, 그룹 1과 2 그리고 3의 일간 TAN 배설률은 각각 637.3$\pm$36.5 mg/kg fish/day, 684.3$\pm$18.5 mg/kg fish/day 그리고 772.8$\pm$17.3 mg/kg fish/day로 나타나 그룹 3의 일간 TAN 배설률이 가장 높은 결과를 보였다. 3일간 절식 후 그룹 1, 2, 그리고 2의 TAN 배설률은 각각 8.08~14.15 mg/kg fish/hr, 6.50~12.20 mg/kg fish/hr, 그리고 6.67~8.60 mg/kg fish/hr의 범위를 보여 거의 일정한 농도로 나타났다. 시간당 TAN 배설률을 적분한 결과, 그룹 1, 2 그리고 3의 일간 TAN 배설률은 각각 286.9$\pm$28.3 mg/kg fish/day, 215.7$\pm$5.5 mg/kg fish/day 그리고 179.3$\pm$7,7 mg/kg fish/day로 나타나 먹이 공급과는 달리 내인성 TAN 배설의 경우 그룹 1의 배설률이 가장 높은 결과를 보였다. 1회 만복 먹이 공급에 따른 TAN 배설 경향은 그룹 1과 2의 TAN 배설률은 먹이 공급 6시간 후 가장 높은 값인 44.19$\pm$2.90 mg/kg fish/hr와 41.70$\pm$1.40 mg/kg fish/hr을 보였고, 그룹 3에서는 4시간 후에 가장 높은 값인 31.23$\pm$1.39 mg/kg fish/day로 나타났다. 일간 먹이 공급에 따른 각 실험구의 총 분 배출량은 그룹 1의 경우 총 분 배출량은 2.17$\pm$0.1 g/kg fish와 91.15$\pm$4.53 g/kg feed로 나타났고, 그룹 2에서는 2.26$\pm$0.14 g/kg fish와 95.02$\pm$3.18 g/kg feed, 그룹 3에서는 2.81$\pm$0.73 g/kg fish와 132.85$\pm$34.0 g/kg feed로 나타나 유의적인 차이는 보이지 않았으나(P>0.05), 그룹 3의 배출 비율이 높은 것으로 나타났다. 시간 경과에 따른 분 배출 비율은 그룹 1의 경우 먹이 공급 24시간 후 총 분의 60.6%를 보여 반면, 그룹 2와 3에서는 각각 67.8%와 77.8%를 보여 그룹 1이 다른 그룹에 비해 분 배출 비율이 낮은 것으로 나타났다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.380-391
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• 1993

The experimental study was made to propose the treatment method of wastewater in the high-density fish culture system. The BOD to COD ratios of effluents were almost same to 0.65 in the eel-farm, but were various in the farm rearing together with tilapia etc. A BOD rate curve of the eel-farm effluent could be described mathematically by the equation, $BODu=14.1(1-10^{-0.222t})+30.9(1-10^{-0.035(t-8)})$. Nitrification in Biological Fluidized Bed(BFB) system to treat the fish-farm wastewater could be reduce ammonium level up to $65{\sim}79\%$ when ammonium loading rates were between 0.014 and 0.075g $NH_4/g$ BVS-day. Nitrification efficiency was decreased by organic matters in the wastewater when ammonium loading was low(0.014 g $NH_4/g$ BVS-day). T-N removal ratios were decreased to increase loading in denitrification process, because of low C/N ratio. Based on much higher biological mass concentrations, BFB system takes many advantages of a practical viewpoint, such as stability of treatment efficiency and reduction of necessary site area for the facility, as compared with conventional treatment systems.