• 한국물환경학회지
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• 제20권6호
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• pp.583-588
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• 2004

This research examined the treatment efficiency and methane production rate in treating slurry-type swine waste using UASB (upflow anaerobic sludge blanket) reactor. The UASB reactor was operated at an organics volumetric loading rate (VLR) of $2.6-15.7kgCOD/m^3/day$. A stepwise increase of the VLR resulted in a temporary deterioration in the COD removal rate in UASB reactor but recovered quickly. The COD removal rate were 65-70% for VLR up to $5 kgCOD/m^3/day$. When organics VLR was $10kgCOD/m^3/day$, the COD removal rate decreased sharply and there was loss of 17.537g of the seeding biomass due to sludge washout. This result indicated that the UASB system cannot be adapted to more than $10kgCOD/m^3/day$ of VLR. As the organic load increased from 2.6 to $15.7kgCOD/m^3/d$, the biogas production rate varied from 3.2 to 10.8 L/d and the methane conversion rate of the organic matter varied from 0.30 to $0.23m^3CH_4/kg\;COD_{removed}$. The methane content showed the range of 70.1-81.5% during the experimental period. The volatile solids (VS) removal efficiency was similar at the low VLR (< $5 kgCOD/m^3/day$), but it decreased sharply at the high VLR (> $5 kgCOD/m^3/day$). The VS reduction rate was, moreover, large those of COD. The result shows that hydraulic retention time above 2 days is essential in case of treating wastewater containing 1% of solids.

• 한국축산시설환경학회지
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• 제6권2호
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• pp.73-81
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• 2000

A two-phase anaerobic digestion system for the treatment of swine waste was constructed in a commercial hog farm. The digester system was composed of 4 major units; slurry storage pit, acidogenic digester, methanogenic digester and sedimentation pit. A biogas boiler unit was also attached to maintain the digester temperature of 37$^{\circ}C$. Substrate lading was made with 2hr-interval by pumping about 2.1$m^3$ of slurry type swine waste from the slurry pit into the acidogenic digester, which corresponds to hydraulic retention time of 4 days for the acidogenic digester and of 11 days for the methanogenic digester. Digester temperature were well maintained as the set temperature of 37$^{\circ}C$ in the methanogenic digester, while the temperature in the acidogenic digester showed around 34$^{\circ}C$. pH also showed a steady-state results of 7.3 in the acidogenic digester and of 7.6 in the methanogenic digester during the operation period. Average biogas production rate was 0.66$m^3$/$m^3$ digester volume. Reduction rate of total solid and volatile solid were 42.8% and 5.8%, respectively. Total nitrogen and ammonia nitrogen were not reduced during the anaerobic fermentation, however, most of VFAs seemed to be converted to the biogas,. These fermentation performance data may suggest that he newly developed a two-phase anaerobic digester for the swine waste treatment worked so successfully.

• Environmental Engineering Research
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• 제13권4호
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• pp.203-209
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• 2008

This paper presents the experimental results in five months operation from a combined anaerobic/oxic system treating swine waste with average concentrations in organic matter and nitrogen of 7,930 mgCOD/L and 671 mgTKN/L, respectively. The system was formed using an upflow anaerobic sludge blanket (UASB) reactor and oxic reactor connected in series with a recycling line of oxic effluents to UASB for its denitrification. The UASB reactor was operated at an organic volumetric loading rate (VLR) of $2.1{\sim}4.5\;kgTCOD/m^3$/day and the removal efficiency of TCOD was $66.3{\sim}85.4%$. The overall removal efficiency of TCOD was more than 99%. The oxic reactor was operated at a nitrogen VLR of $0.10{\sim}0.20\;kgTKN/m^3$/day and the nitrification efficiency was 75%. However, the complete denitrification was observed in the UASB reactor that was due to the optimal temperature and sufficient carbon source. The overall removal rate of TN was about 80%. About 76.2% of the influent COD mass was accountable in a COD mass balance at a level of VLR $3.64\;kgCOD/m^3$/day. The production rate of methane was $0.32\;LCH_4/gCOD_{removed}$ when influent organics, VLR, were recorded by $3.4{\sim}4.5\;kgCOD/m^3$/day.

• 유기물자원화
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• 제7권1호
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• pp.43-52
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• 1999

본 연구는 축산분뇨 퇴비화시 부자재인 톱밥을 석탄회로 대체하기 위하여 수행하였다. 축산분뇨와 톱밥의 혼합비율을 부피비 1:1로 고정하고 이때 톱밥을 어느 정도 석탄회로 대체 가능한지를 조사하였다. 각 혼합비율에 대해 조사된 톱밥과 석탄회의 혼합비율은 부피비로 40:10, 35:15, 30:20, 25:25, 20:30, 15:35, 10:40이었다. 축사에서 스크레퍼 방식과 슬러리 방식에 의하여 배출되는 축산분뇨, 톱밥과 석탄회를 앞에서와 같은 혼합비율로 섞은 부자재를 부피비 1:1로 혼합하여 퇴비화하면서 온도, 수분, pH, 유기물, 질소 및 유기물/질소 비 등을 조사하여 다음과 같은 결과를 얻었다. 온도의 변화는 슬러리 방식보다 스크레파 방식에서 톱밥비율이 높을수록 빨리 최고온도($63.5^{\circ}C$)에 도달하였다. 수분 함량의 변화는 스크레파 방식 및 슬러리 방식 공히 톱밥과 석탄회를 부피비로 동일비율(1:1) 혼합하였을 때 42 %와 54 % 범위의 수분함량으로 발효에 비교적 좋은 조건을 유지하였다. pH는 분뇨, 톱밥, 석탄회 비율 50 : 25 : 25 투입시 전체적으로 pH 7~10으로 약알카리성 내지 알카리성이었다. 유기물함량은 톱밥 혼입량이 석탄회보다 많을수록 증가되나 퇴비화가 진행됨에 따라 별다른 변화는 보이지 않았다. 질소함량은 톱밥 혼입량 증가에 따라 늘어났으나, 발효과정 진행에 따라서는 일정한 경향을 나타내지 않았다. 유기물/질소 비는 톱밥 혼입량이 증가할수록 증가하였지만, 발효과정 중 큰 변화는 볼 수 없었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.65-66
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• 2005

Anaerobic digestion is one of the well-known methods for biological treatment handling of concentrated organic matter such as swine $wastewater.^{1)} The anaerobic digestion can reduce organic loading but also hydrolyze non-biodegradable organic $matter.^{2)}$ The feces from the scrapper-type barn are usually collected to make compost and the urine is discarded with swine-slurry wastewater by ocean-dumping or treated by biological methods. The lagoon, aerobic digestion, anaerobic digestion, SBR, $A^{2}/O$, and UCT have been applied for treating swine $wastewater.^{3)} In this study, as a result of the analysis of swine wastewater, the total and soluble chemical oxygen demand was 130g/L and 60g/L, respectively. And the volatile fatty acid as chemical oxygen demand equivalent was 45g/L, which was 75% of soluble chemical oxygen demand. Before everything else, ammonia nitrogen concentration was 6.5 g/L. From biochemical acidogenic potential test, it was concluded that the enhanced acidification process to manage swine waste should be operated in the ammonia nitrogen concentration of less than 1.2 g/L. In the result of seeding ratio experiments with artificial $wastewater^{4)}, the lag period of acidogens was taken the long time because of the inhibition by the $ammonia^{5)}$, however no difference of period by the seeding ratio was not shown. The Haldane-based biokinetics were also evaluated using a method of fourth order Runge-Kutta $approximation.^{6,7)}$ The nonlinear least squares (NLLS) method with a 95% confidence interval was also used. The ranges of maximum microbial growth rate, ${/mu_{max}}$, and half saturation coefficient, $K_{s}$, for acidogenesis of various seeding ratio with artificial wastewater were 6.1 ~ 12.6 $d^{-1}$ and 45,000 ~ 53,500 mg glucose/L, respectively. Also, the methanogenic microbial yield coefficient, Y, and microbial decay rate coefficient, $k_{d}$, and inhibition substrate concentration, $K_{si}$, for the reactors were determined to be 0.32 ~ 0.465 ${/mu}g$/mg glucose; 0.42 ~ 1.01 $d^{-1}$ and 51,500 ~ 55,600 mg glucose/L, respectively.