• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.387-390
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• 2007

The mixing characteristics of heated water discharged from different types of effluents are simulated using a commercial software, Flow-3D model. In order to verify the model, the comparison of numerical results with the experimental data are conducted for each type of effluent, the submerged and surface overfall. It is observed that the numerical results show a reasonable agreement with the experimental data. Based on this study the application to the heated water discharge problem in the field can be expected as a further study and it can be the fundamental data when determining the type of effluent in a powerplant.

• Water Engineering Research
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• 제6권1호
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• pp.1-15
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• 2005

The numerical model, FLUENT, was employed to investigate the effect of the heated water discharged from the diffuser of Boryung Power Plant. Temperature patterns of the thermal effluent discharged from two proposed types of the diffusers was evaluated for maximum flood and maximum ebb tide. The hydraulic model experiments were also performed in the reduced scale of 1/150 to verify the numerical simulation results. The buoyant jets discharged from the diffusers were found to be significantly affected by the ambient flows beyond the region where the effluent momentum was dissipated. Both the numerical and experimental results showed that the area of the excess isotherm for Type 1 diffuser was larger than that for Type 2 diffuser. Type 2 diffuser system was observed to be a more effective diffuser design than Type 1 diffuser system based on the temperature reduction and excess isotherm obtained from the numerical simulation in the ambient flows.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.190-190
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• 2011

In South Korea the gross generation and heated effluent of power generation plant was 259 TWh and 4.73 billion tons in 2008. And then the waste heat from power generation was 388 TWh. It shows that the efficiency of thermal power generation plant is about 40%. Therefore to reduce $CO_2$ emission from thermal power generation plant, the energy of this heated effluent must be reused to heat buildings or farm facilities. In South Korea horticultural facilities of about 25% are heated in winter season. Total area of greenhouses which are heated is about 13,000 ha. Total heat amount needed to warm greenhouse of 13,000 ha in winter season is only 3.4% of total waste heat from power generation plant. In this study a heat pump system was designed to reuse the waste heat from power generation. Especially new heat exchanger was developed to recover the thermal energy from waste water and this model considered anti-corrosion against sea water and low cost for economic feasibility. This heat recovery system was installed in mango growing greenhouse around thermal power generation plant in Seogwipo-city, Jeju Special Self-Governing Province. The result of preliminary test shows that the heating cost of about 90% is saved as compared to boiler using tax free light oil as a fuel.

• Korean Journal of Hydrosciences
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• 제6권
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• pp.67-79
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• 1995

The reattachment of buoyant efflluent to a shore in a crossflow is investigated experimentally. The effluent is prodeced by discharging heated water through a projected side channel into a confined crossflow of the same depth. In the projecting effluent, the size of recirculating region, which is formed by deflected thermal plume on the lee of the effluent, tends to increase, but the maximum temperature decreases in the direction of the crossflow and it has more uniform transverse spreading compared to non-projected type. The heat flux across the crossflow is found to be independent of the projceted length of the side channel under relatively high buoyancy flux on the contrary to low buoyancy flux. The reattachment of th effluent can be specified by both velocity ratio and densimetric Froude number, whereas only the velocity ratio is governing factor to the reattachment of the effluent in the case of non-projecting type.

• 생물환경조절학회지
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• 제21권4호
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• pp.372-378
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• 2012

본 연구에서는 화력발전소에서 온배수의 형태로 배출되는 폐열을 히트펌프의 열원으로 이용하여 온실의 난방에 활용할 수 있는 히트펌프 시스템을 설계 제작하였으며, 난방 성능을 분석하여 PE 파이프 열교환기의 설계기준을 제시하고자 하였다. PE 파이프 열교환기의 내경은 20mm, 두께는 2mm였으며, Roll의 직경은 1,000mm로 하였다. 연구결과 PE파이프 열교환기의 적정 길이는 1.0RT당 75m로 설계하는 것이 바람직할 것으로 판단되었으며, 이때 히트펌프시스템의 난방성능계수(COPh)는 3.8로 나타났다.

• 한국양식학회지
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• 제15권4호
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• pp.267-273
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• 2002

고수온기인 여름철 발전소와 인접하여 온배수 방류수 역의 해수를 양식용수로 사용하는 온배수 수역내 양식장(온수양식장)과 발전소로부터 15 km떨어져 있어 온배수 영향이 없는 양식장(대조양식장)에서 사육되고 있는 넙치의 혈액을 채취하여 혈액의 일반성상, cortisol 및 삽투질 농도 등을 서로 비교하였다. 두 양식장에서 고수온기인 8월 4일, 8월 19일, 9월 4일 및 9월 20일에 채집한 혈액의 Ht는 대조양식장에서 15.7∼16.3%의 범위를 보였으나, 온수양식장은 11.4∼l7.7%로 나타났다. 대조양식장에서 cortisol 농도는 0.6∼2.8 ng/$m\ell$의 범위를 나타낸 반면, 온수양식장은 8월 3일 317.1 ng/$m\ell$로 실험기간중 가장 높은 값을 보였다.

• 설비공학논문집
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• 제29권8호
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• pp.391-400
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• 2017

Understanding of seawater fouling characteristics is critical in designing a heat exchanger adapted in an effluent utilization system for a power plant. We reviewed three types of fouling mechanisms of general, biological, and crystallizing for a plate-frame heat exchanger, to be used for heat exchanging with heated effluent from a power plant. Also, mathematical models for each type of seawater fouling were suggested. Actual thermal resistance calculated from seawater fouling models were compared and implemented in designing a plate-frame heat exchanger. The bio-fouling model revealed the largest thermal resistance and the highest number of plates for a plate-frame heat exchanger under the same heat load. Overall heat transfer coefficient and pressure drop of a plate-frame heat exchanger under fouling conditions was lower by 58 percent and higher by 2.85 times than those under clean conditions, respectively.

• 한국축산시설환경학회지
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• 제9권1호
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• pp.45-56
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• 2003

$TAO^{TM}$ System is an auto-heated thermophilic aerated digestion process using a proprietary microbe called as a Phototropic Bacteria (PTB). High metabolic activity results in heat generation, which enables to produce a pathogen-free and digested liquid fertilizer at short retention times. TAO$^{TM}$ system has been developed to reduce a manure volume and convert into the liquid fertilizer using swine manure since 1992. About 100 units have been installed and operated in Korean swine farms so far. TAO$^{TM}$ system consists of a reactor vessel and ejector-type aeration pumps and foam removers. The swine slurry manure enters into vessel with PTB and is mixed and aerated. The process is operated at detention times from 2 to 4 days and temperature of 55 to $65^{\circ}C$. Foams are occurred and broken down by foam removers to evaporate water contents. Generally, at least 30% of water content is evaporated, 99% of volatile fatty acids caused an odor are removed and pathogen destruction is excellent with fecal coliform, rotavirus and salmonella below detection limits. The effluent from TAO$^{TM}$ system, called as the "TAO EFFLUX", is screened and has superb properties as a fertilizer. Normally N-P-K contents of screened TAO Efflux are 4.7 g/L, 0.375 g/L and 2.8 g/L respectively. The fertilizer effect of TAO EFFLUX compared to chemical fertilizer has been demonstrated and studied with various crops such as rice, potato, cabbage, pumpkin, green pepper, parsley, cucumber and apple. Generally it has better fertilizer effects and excellent soil fertility improvement effects. Moreover, the TAO EFFLUX is concentrated through membrane technology without fouling problems for a cost saving of long distance transportation and a commercialization (crop nutrient commodity) to a gardening market, for example.

• 유기물자원화
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• 제11권3호
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• pp.75-86
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• 2003

최근에는 차집관거의 확충, 생활하수의 유입량 증가 및 인근 신규 APT의 분뇨 직유입으로 인해 유입 총고형 물량이 증가됨에 따라 기존 소화조의 용량이 부족할 것으로 예상되고 있다. 본 연구는 기존 소화조 용량부족에 따른 효율감소에 대응하기 위해 미생물제재로써 Bio-dh를 이용하여 소화조내 소화효율 증가(유기물 분해속도 증가)에 따른 최종슬러지 발생량을 감소시키고 가스발생량을 증가시키는데 그 목적이 있다. 실제 하수슬러지를 처리하고 있는 소화조 장치와 동일한 2단혐기성소화조 형태로 설치하였으며, 용량이 $1.3m^3$인 혼합조에 하수슬러지와 미생물제재인 Bio-dh를 주입하였다. 소화방식은 중온성 2단혐기성소화조로서 $35{\pm}1^{\circ}C$를 유지하였고, 1단소화조는 반응조내 미생물과 기질의 원활한 혼합을 위하여 교반기를 부착하였으며, 교반기는 120rpm으로 운전하여 반응조내 완전혼합이 이루어지도록 운전하였다. 2단소화조에서는 소화슬러지와 상등수가 분리되도록 교반을 수행하지 않았다. 소화가스량 측정을 위하여 각 소화조 상부에 가스메타를 설치하였으며, 가스분석을 위하여 상부에 가스포집구를 설치하였다. 교반기 축사이로 발생할 수 있는 발생가스의 누출과 공기의 유입을 막기 위해 water sealing 장치를 교반기 축에 부착시켰다. 실험결과 다음과 같은 결론을 얻을 수 있었다. 1. 미생물제재를 투입하지 않은 경우 소화효율은 평균 48.6%(46.0~50.9%)로 나타난 반면, 미생물제재인 Bio-dh를 투입한 경우 소화효율은 평균 54.2%(52.8~57.3%)로 나타나 미생물제재를 투입한 경우가 미생물제재를 투입하지 않은 경우보다 소화효율이 약 1.12배 정도 높은 것으로 나타났다. 2. 2차소화조 월류수의 수질은 미생물제재 미투입시 $COD_{Mn}$은 평균 1,639mg/L, SS는 평균 4,888mg/L로 나타난 반면, 미생물제재(Bio-dh) 투입시 $COD_{Mn}$은 평균 859mg/L, SS는 평균 2,405mg/L로 나타나 미생물제재 투입시 $COD_{Mn}$은 약 47.6%, SS는 약 50.8% 정도 더 낮게 나타났다.