• 한국환경보건학회지
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• 제18권2호
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• pp.75-81
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• 1992

An experimental investigation has been carried out to evaluate the characteristics in wastewater treatment using an anaerobic packed bed bioreactor with ceramics, rubber sponge, soft stone A, and soft stone B as carrier. The results of the work have shown that soft stone A as a carrier was superior to other carriers in methane production, then the content of methane for soft stone A was about 70%. First of all, soft stone A had higher efficiency of the COD removal than the others in response of passing the operation, as well as it had a low volatile acid in reactor. In addition, the slope of methane production with respect to the removal of COD ($m^{3}CH_{4}$/kgCOD) was 0.58 for soft stone A. In biomass hold-up equation for each carriers, the equation of soft stone A was m$_{p}$=714 ($C_{o}/0.41+C_{o}$) and it was the largest in this experimented carriers. Based upon the results obtained, it is suggested that the major effective carrier in wastewater treatments within the packed bed bioreactor used in this experimental work by soft stone A.

• 한국환경보건학회지
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• 제19권3호
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• pp.17-21
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• 1993

Characteristics of a downflow anaerobic packed bed reactor with raschig ring ceramics as a packing were measured and discussed for the basic evaluation of the process. A synthesized glucose substrate wastewater were used as a feed and process characteristics such as pH, biogas production, composition of produced gas, COD removal and VSS were measured with the hydraulic retention time (HRT) changing from 0.25 to 2 days. As a result, this type of reactor was applicable in continuous operation within the given HRT range and the transient period approaching the steady state was about 20 days. The content of methane in produced gas increase with HRT was always high above 50% enough to use as energy source. The COD removal efficiency increased gradually as HRT increased. The axial profile of VSS concentration in the reactor usually showed the maximum at the lower region and the minimum at the middle. The VSS concentration at the upper region and the exit appeared similarly. However, at 0.25 day of HRT, the VSS concentration of effluent became higher than that of the upper region. Therefore the optimum HRT of this reactor occurred about 0.5 day, at which the production of methane began to be just stabilized and loss of VSS and COD removal were resonable.

• 대한환경공학회지
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• 제31권8호
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• pp.655-662
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• 2009

원통형 여과장치의 실규모 설계 및 운전에 필요한 기초자료를 얻기 위하여 산출유량을 단계적으로 증가시키는 파일럿 실험을 수행하면서 수질지표들과 폐색도 진행을 조사하였다. 유량을 0.8 L/min에서 2.4 L/min로 증가시키는 경우 BOD, SS, 그리고 탁도의 제거율은 각각 약 80%, 95% 이상, 그리고 90% 이상으로 거의 일정하게 유지되었으나 COD 제거율은 44%에서 29%로 감소하였다. 산출유량이 증가할수록 오염물 단위농도를 제거하는데 소요되는 체류시간은 감소하였으며, 1 mg-COD/L를 제거하는데 필요한 체류시간은 산출유량 0.8 L/min인 경우 83분이었고 2.4 L/min에서는 45분이어서 양수율이 낮은 것보다는 높은 것이 호소의 오염제거에 더 유리함을 알 수 있었다. 여과장치의 폐색은 표층에서 집수관쪽으로 진행하며, 산출유량이 증가하면 폐색도도 증가하지만 2년 이상의 운전에도 폐색이 문제되지는 않아 본 장치가 호소의 수질개선에 효과적으로 사용될 수 있을 것으로 기대되었다.

• 유기물자원화
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• 제11권1호
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• pp.70-76
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• 2003

소화슬러지를 열처리한 혼합 배양 미생물을 식종균으로, 자당을 기질로 사용하는 혐기성 수소 생산 공정을 운전하면서 pH 조절, 반복 열처리, 기질 농도 변화 등을 통해 지속적인 수소 생산 방법을 고찰하였다. 유입 기질의 농도가 5g COD/L인 경우 운전 초기에는 $0.5mole\;H_2/mole\;hexose$ 이상의 수소가 발생하지만 9일 이상 지속되지 못하였다. 이러한 현상의 원인은 수소 생성균이 공정 내에서 고농도로 존재하지 못하기 때문인 것으로 판단되며 pH를 5.3으로 유지하는 것만으로는 극복될 수 없었다. 반복 열처리를 적용할 경우 별도의 식종균 재주입 없이 효율이 감소된 수소 생성 공정을 원상태로 복구할 수 있음을 확인할 수 있었으나, 수소 생성 효율이 시간에 따라 감소하므로 열처리를 자주 해야 하는 문제가 발생했다. 유입 기질의 농도가 30g COD/L인 경우에는 24일간 지속적인 수소 생성이 가능하였으며, CSTR의 경우 $1.0-1.4mole\;H_2/mole\;hexose$, ASBR의 경우에는 $0.2-0.3mole\;H_2/mole\;hexose$의 생성 효율을 보였다. 수소 생성 시 유출수 내 용존성 유기물의 90% 이상은 유기산이었으며 그 중 n-butyrate가 가장 많은 양을 차지하였다.

• 한국물환경학회지
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• 제21권6호
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• pp.643-650
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• 2005

In order to treat leachate from aged landfill site effectively, removal of biologically recalcitrant organic matter and denitrification efficiency were evaluated through the combination of $H_2O_2/O_3$ AOP pretreatment process and UASB process. The results can be summarized as follows. In case of leachate having low COD/N ratio from aged landfill site, it is possible to increase available COD for denitrification in nitrate utilizing denitrification and nitrite utilizing denitrification both by enhancing biodegradability of recalcitrant organic matter as applying $H_2O_2/O_3$ AOP to pretreatment process. In this experiment, it is found that available COD for denitrification can be increased to 1.0 and 0.4 g/day, respectively. Comparison has been made between requiring COD and available COD for denitrification in each experimental stages. It is expected that high rate of denitrification can be achieved with leachate from young landfill site because higher amount of available COD for denotrification is present in the leachate than the amount of requiring COD for denitrification. Especially, In leachate from aged landfill site with low COD/N ratio, it can be concluded that denitrification using nitrite nitrogen can enhance overall denitrification performance efficiently because denitrification using nitrite nitrogen requires less amount of carbon source than denitrification using nitrate nitrogen. Comparing the biogas production rate and nitrogen content of biogas under the condition of same amount of nitrate and nitrite addition, biogas production and nitrogen content of biogas are increased during denitrification after $H_2O_2/O_3$ AOP pretreatment process. Therefore, it can be confirmed that COD/N ratio in the leachate is increased. Applying $H_2O_2/O_3$ AOP as pretreatment system of landfill leachate seems to have little economic benefit because it requires additional carbon source to denitrify ammonia nitrogen in leachate coming from aged landfill site. However, it is possible to apply this pretreatment process to leachate from old landfill site in view of AOP process can achieve removal of biologically recalcitrant organic matter and increase of available COD for denitrification simultaneously.

• 유기물자원화
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• 제3권2호
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• pp.37-45
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• 1995

유가공폐수 처리를 위한 UASB 의 성능과 운전상의 문제점을 조사하였다. 인공 유가공폐수는 부하3.9kg $COD/m^3.day$까지 성공적으로 운전이 가능하였으며, 이 때 90% 이상의 COD 제거율과 단위 체적당 1.23 I/I.day 의 가스가 발생하였다. 그러나, 부하 2.1kg $COD/m^3.day$ 에서는 침전부 표변에 스컴층이 형성되면서 슬러지부상과 유실이 관찰되었다. 혈청병 (SBT) 실험으로 측정된 우유공장 실폐수와 아이스크림폐수의 생화학적 메탄생성능(BMP) 은 각각 0.135, 0.66ml $CH_4/mg\;COD_{added}$이었다. 반응조의 슬러지 활성도는 식종 초기에 0.159g $COD-CH_4/g$ VSS.d 에서 운전 90 일이 경과하는 동안에 8배 이상 증가하였다.

• 한국환경보건학회지
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• 제20권2호
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• pp.22-27
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• 1994

This study is to discuss the factors influenced on the removal efficiency of a high-strength organic wastewaters investigated using the polypropyrene media which appropriate to attach microorganism in the tube type fixed biofilter reactor. The results obtained in the experiment were as follows: 1. The kinetics of reaction rate (k') were 0.125, 0.135, 0.155 varing initial COD 720, 1280, 1630 mg/l in batch reactor. 2. In the range of pH 4.0 ~12.0 was obtained the removal efficiency of COD higher than 85%. It was proved that variation of pH (4.0 ~12.0) was nothing to do with the removal efficiency of substrate in continuous reactor. 3. Temperature to obtain removal efficiency of COD higher than 85% was 10 ~ 40$\circ$C. Removal efficiency of COD was no less than those at high temperature. 4. In the continuous reactor, the volumetric loading of COD for removal efficiency higher than 95% had to be 0.5~1.5 kg COD/m$^3$.d below. And then the HRT was 8 hrs. 5. In comparison with the activated sludge process, the tube type fixed biofilter process was excellent in removal efficiency of substrate and sludge production rate.

• 대한토목학회논문집
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• 제10권4호
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• pp.185-192
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• 1990

본 연구에서는 주정폐액의 고율처리를 위하여 이상 UASB 공정을 시험하였다. 상분리는 반응조의 pH를 조절하므로써 가능하였다. 유입폐수의 SS 농도가 4.1g/l일 때 산형성조는 유기부하 16.5kg $COD/m^3.day$까지 운전이 가능하였고, 이때 산생성율은 3.9g HAc/l.day를 나타내었다. 메탄형성조는 유기부하 44kg $COD/m^3.day$까지 운전이 가능하였으며, 이때 COD 제거율은 80%이었고 비가스 생성율은 16.51/l.day이었다. 두 반응조에서 입상슬러지가 형성된 이후에는 알칼리도의 주입없이 메탄조유출수의 재순환으로 산형성조의 pH를 적절하게 유지할 수 있었다.

• 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.

• Environmental Engineering Research
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• 제19권4호
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• pp.387-393
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• 2014

The purpose of this study is to evaluate integrated anaerobic hydrogen fermentation and membrane bioreactor (MBR) for on-site domestic wastewater treatment and resource recovery. A synthetic wastewater (COD 17,000 mg/L) was used as artificial brown water which will be discharged from urine diversion toilet and fed into a continuous stirred tank reactor (CSTR) type anaerobic reactor with inclined plate. The effluent of anaerobic reactor mixed with real household grey water (COD 700 mg/L) was further treated by MBR for reuse. An optimum condition maintained in anaerobic reactor was HRT of 8 hrs, pH 5.5, SRT of 5 days and temperature of $37^{\circ}C$. COD removal of 98% was achieved from the overall system. Total gas production rate and hydrogen content was 4.6 L/day and 52.4% respectively. COD mass balance described the COD distribution in the system via reactor byproducts and effluent COD concentration. The results of this study asserts that, anaerobic hydrogen fermentation combined with MBR is a potent system in stabilizing waste strength and clean hydrogen recovery which could be implemented for onsite domestic wastewater treatment and reuse.