• 한국환경보건학회지
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• 제28권1호
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• pp.51-65
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• 2002

This study was carried out to apply some basic physical and chemical treatment options including Fenton's oxidation, and to evaluate the performances and the characteristics of organic and nitrogen removal using lab-scale biological treatment system such as complete-mixing activated sludge and sequencing batch reactor(SBR) processes for the treatment of leachate from a municipal waste landfill in Gyeongnam province. The results were as follows: Chemical coagulation experiments using aluminium sulfate, ferrous sulfate and ferric chloride resulted in leachate CO $D_{Cr}$ removal of 32%, 23% and 21 % with optimum reaction dose ranges of 10,000～15,000 mg/$\ell$, 1,000 mg/$\ell$ and 500～2,000 mg/$\ell$, respectively. Fenton's oxidation required the optimum conditions including pH 3.5, 6 hours of reaction time, and hydrogen peroxide and ferrous sulfate concentrations of 2,000 ～ 3,000 mg/$\ell$ each with 1:1 weight ratio to remove more than 50% of COD in the leachate containing CO $D_{Cr}$ between 2,000 ～ 3,000 mg/$\ell$. Air-stripping achieved to remove more than 97% of N $H_3$-N in the leachate in spite of requiring high cost of chemicals and extensive stripping time, and, however, zeolite treatment removing 94% of N $H_3$-N showed high selectivity to N $H^{+}$ ion and much faster removal rate than air-stripping. The result from lab-scale experiment using a complete-mixing activated sludge process showed that biological treatability tended to increase more or less as HRT increased or F/M ratio decreased, and, however, COD removal efficiency was very poor by showing only 36% at HRT of 29 days. While COD removal was achieved more during Fenton's oxidation as compared to alum treatment for the landfill leachate, the ratio of BOD/COD after Fenton's oxidation considerably increased, and the consecutive activated sludge process significantly reduced organic strength to remove 50% of CO $D_{Cr}$ and 95% of BO $D_{5}$ . The SBR process was generally more capable of removing organics and nitrogen in the leachate than complete-mixing activated sludge process to achieve 74% removal of influent CO $D_{Cr}$ , 98% of BO $D_{5}$ and especially 99% of N $H_3$-N. However, organic removal rates of the SBR processes pre-treated with air-stripping and with zeolite were not much different with those without pre-treatment, and the SBR process treated with powdered activated carbon showed a little higher rate of CO $D_{Cr}$ removal than the process without any treatment. In conclusion, the biological treatment process using SBR proved to be the most applicable for the treatment of organic contents and nitrogen simultaneously and effectively in the landfill leachate.e.

• 한국환경과학회지
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• 제3권4호
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• pp.417-425
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• 1994

Leachate from municipal landfill site is known to be hard to treat because it commonly contains various toxic material and heavy metals. In addition, portions of biodegradable organic substances in leachate are decreasing in the course of wastes stabilization, which is one of the critical reason for inefficient biological treatment at the end stage of landfill site operation. So this study was conducted to examine the feasibility of municipal lanuill leachate pretreatment using electrolysis. The optimum electrode combination was made. The optimum electrode combination was found to be lead and graphite.

• 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.

• 한국환경보건학회지
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• 제26권4호
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• pp.129-133
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• 2000

The objective of this study was to invetigate the coagulation effects of landfill leachate by using Acid Mine Drainage(AND). The coagulation efficiency was investigated by mixing landfill leachate with F $e^{+3}$ solution earned by oxidation of pyrite(AMD). In the results of this experiment, it was found that the amount of removed COD and SS was approximately 30% respectively by mixing at the ratio of AMD three to leachate one. And it showed highest turbidity removal efficiency at all mixing ratio. Concentration of Fe was decreased with increasing mixing ratio, however it was increased inversely at mixing ratio 4. Optimal mixing ratio was 3 at the results obtained by leachate coagulation experiments. Also removal efficiency at mixing ratio 3 corresponded to 500mg/$\ell$ of FeC $l_3$ dosage. it was suggested that pretreatment by mixing of AMD and leachate remove both suspended organic material of leachate and metal of AMD.

• Environmental Engineering Research
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• 제22권2호
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• pp.157-161
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• 2017

Simultaneous treatment of food waste leachate and power generation was investigated in an air-cathode microbial fuel cell. A TCOD removal efficiency of $95.4{\pm}0.3%$ was achieved for an initial COD concentration of 2,860 mg/L. Maximum power density ranged was maximized at $1.86W/m^3$, when COD concentration varied between 60 mg/L and 2,860 mg/L. Meanwhile, columbic efficiency was determined between 1.76% and 11.07% for different COD concentrations. Cyclic voltammetric data revealed that the oxidation peak voltage occurred at -0.20 V, shifted to about -0.25 V. Moreover, a reduction peak voltage at -0.45 V appeared when organic matters were exhausted, indicating that reducible matters were produced during the decomposition of organic matters. The results showed that it was feasible to use food waste leachate as a fuel for power generation in a microbial fuel cell, and the treatment efficiency of the wastewater was satisfied.

• 한국축산시설환경학회지
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• 제16권3호
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• pp.215-226
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• 2010

본 연구는 목편살수여상 pilot 장치를 설치하여 스크레파 축사에서 배출되는 뇨오수를 원수로 사용하여 가동한 후 침출액비를 공시재료로 하여 상추 양액재배 시험을 실시하였다. 처리구는 침출액비 (SL) 단독처리구, 침출 액비+어분 (SL+FM), 침출액비+골분 (SL+BM), 침출액비+게껍질 (SL+CS) 혼합처리구. 침출 액비+부산물 (SL+FM+BM+CS) 혼합처리구, 대조구로 원예연 상추양액 (NS) 처리구 등 6개 처리구를 두었다. 침출액비와 부산물 혼합처리 후 전기전도도와 pH를 조정하여 상추의 양액재배를 실시한 결과를 요약하면 다음과 같다. 1. 목편살수여상 처리 과정중 pH는 처리 시작전 7.3에서 처리 후 8.5로 상승하였다. 전기전도도 (EC)는 처리전 17.05 mS/cm에서 처리 후 30일에는 9.7 mS/cm로 낮아졌다. 2. 침출액비는 부유물질 (SS)이 낮아 수경 재배시 관배수의 막힘문제 없이 활용이 가능하였다. 침출액비는 양분조성에서 칼륨함량이 높고 인산 함량이 낮았다. 3. 침출액비시용구 (SL)의 상추수량은 원예 연 표준양액재배 대비 75%를 나타내어 25% 수량저하를 나타내었다. 침출액비을 어분. 골분. 게껍질을 혼합한 처리구는 대조구 대비 85%. 79%. 80% 수량을 나타내어 어분의 첨가 효과가 가장 높았다. 침출액비와 어분 혼합액은 침출액비 단독처리구 보다 10% 증수를 나타내어 유기양액의 대체 원료로 사용이 가능 할 것으로 보인다.

• 유기물자원화
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• 제24권2호
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• pp.41-49
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• 2016

P시에서는 음폐수 처리를 위해 병합처리시설을 설치하였으나, 음폐수 발생량 대비 처리용량이 부족한 실정이다. 또한 병합처리시설 방류수는 인근 바다로 직방류 되고 있어 환경적 문제가 발생할 수 있다. 따라서 본 연구에서는 P하수처리장을 대상으로 P시 발생 음폐수 처리 초과 분량 및 병합처리시설 방류수 연계처리 가능성을 검토하였다. 예상 가능한 4개의 시나리오를 세운 후, 각각의 최대 음폐수 및 병합처리시설 방류수 허용 투입량을 산정 하고, 투입 후 P하수처리장 유입수 성상 변화및 시나리오별 예상 처리비용을 비교 하였다. 검토된 모든 시나리오에서 환경부의 음폐수 병합처리 업무지침을 준수하면서 음폐수 및 병합처리시설 방류수 대부분을 P하수처리장에 연계 처리 가능하며 하수처리장 부하에도 큰 영향을 주지 않을 것으로 산정 되었다.

• 유기물자원화
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• 제21권4호
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• pp.50-61
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• 2013

교내 식당에서 분리 수거된 음식물류 폐기물에서 재생 에너지인 메탄가스를 생산하기 위해 혐기성 소화시스템에 대한 연구가 수행되었다. 1차 실험에서 침출수 인발/반송도 없고 혼합도 없는, 침출수 인발/반송은 없고 혼합이 있는, 침출수 인발/반송은 있고 혼합이 없는, 그리고 침출수 인발/반송은 있고 혼합이 있는 4개의 혐기성 시스템에서 침출수 인발/반송은 있고 혼합이 없는 시스템에서 가스발생이 가장 많은 것으로 나타났다. 반응조 혼합이 없고 침출수 인발/반송이 수행되는 시스템에서는 침출수의 반응조 내 침출수 유출속도가 빠른 경우에 혐기성 반응이 활발히 일어난 것으로 관찰되었다. 가스수집기 무게가 1kg이고 음식물류 폐기물 C/N비가 10이상이 되는 경우 혐기성 반응조의 가스가 소모되어 가스수집기에 부압이 걸리는 것이 관찰되었는데, 이에 대한 원인을 밝히는 것이 음식물류 폐기물에서 재생에너지를 회수하는데 필수적이다.

• 한국유기농업학회지
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• 제17권3호
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• pp.357-370
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• 2009

본 연구는 돈분뇨 여과 및 농축액비를 이용한 양액재배의 가능성을 검토하기 위하여 여과액비와 농축액비와 부산물, 양액 혼합처리가 토마토 생육에 미치는 영향을 검토하였다. 퇴비화 과정 중 과수분 상태에서 배출되는 퇴비단 여과액비와 막분리 처리과정에서 한외 여과막을 통과하고 역삼투막 처리에서 역류되어 나오는 돈슬러리 농축액비를 공시재료로 하였다. 본 연구는 질소함량을 기준으로 액비와 부산물, 양액의 혼합하는 처리구를 두어 전기전도도와 pH를 조정하여 토마토의 양액재배를 실시한 결과를 요약하면 다음과 같다. 1. 여과액비와 농축액비는 다량 및 미량원소를 함유하고 부유물질(SS)이 낮아 양액재배시 관배수의 막힘문제 없이 활용이 가능하였다. 여과, 농축액비는 인산, 칼슘, 마그네슘 함량이 낮고 칼륨이 높은 양분불균형를 나타내었다. 2. 여과액비는 원예연 표준양액 대비 총수량 91%, 상품수량 70%를 나타내어 여과액비 단독급액으로 토마토의 유기 수경재배 생산이 가능하였다. 3. 막처리 농축액비 100% 처리구는 토마토의 지상부의 생육이 지연되고 과중이 감소되어 화학양액 대비 40%의 수량을 나타내었다. 4. 퇴비단 여과액비+부산물, 농축액비+부산물 혼합처리구의 토마토 수량은 대조구 대비 각각 87, 76%를 나타내어 여과액비 단독시용구의 수량에 미치지 못하였다. 5. 질소기준으로 여과액비와 농축액비에 양액을 50% : 50% 비율로 혼합하여 균형처방 처리한 경우 표준양액 처리와 대등한 수량을 나타내었다. 결론적으로 토마토 양액재배에서 생육과 수량을 고려할 때 액비와 양액의 50 : 50 혼합 재배시 수량이 유지되어 가축분뇨 유래 유기액비에 의하여 화학양액를 50% 대체할 수 있을 것으로 판단된다.

• 환경위생공학
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• 제18권1호
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• pp.23-29
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• 2003

The effect of ozone oxidation on bio-degradability of leachate was studied. Ozone oxidation process was used as pre-treatment process to enhance performance of biological process in treating landfill leachate. Optimum ozone injection rate and contact time in this experiment was $160{\;}mg{\;}O_/{\ell}{\cdot}hr$ and 45 minutes, respectively. Bio-degradability was enhanced 5.08% by ozone oxidation. The ratio of ozone demand/DOC concentration was $0.049~0.091{\;}mg{\;}O_3/mg{\;}DOC$. The increase of bio-degradability depending on ozone injection rate(D) and contact time(T) can be expressed as follows ; The rate of bio-degradation of DOC was increased proportionally with the increase of ozone injection rate and contact time irrespective of landfill site age. The increase of bio-degradability by ozone addition was not satisfactory. It is hard to expect significant increase in bio-degradability by ozone treatment only. Thus, it is evaluated that ozone oxidation can not increase biodegradability significantly in concentrated wastewater composed of complex organic compound such as leachate.