• 수도
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• 통권22호
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• pp.63-78
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• 1980

• 수도
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• 통권23호
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• pp.46-55
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• 1980

• 한국물환경학회지
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• 제34권1호
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• pp.121-131
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• 2018

Domestic sewage treatment plants (STPs) consume about 0.5 % of total electric energy produced annually, which is equivalent to 207.7 billion Korean won per year. To minimize the energy consumption and as a way of mitigating the depletion of energy sources, the sewage treatment strategy should be improved to the level of "energy positive". The core processes for the energy positive sewage treatment include A-stage for energy recovery and B-stage for energy-efficient nitrogen removal. The integrated process is known as the A/B-process. In A-stage, chemically enhanced primary treatment (CEPT) or high rate activated sludge (HRAS) processes can be utilized by modifying the primary settling in the first stage of sewage treatment. CEPT utilizes chemical coagulation and flocculation, while HRAS applies returned activated sludge for the efficient recovery of organic contents. The two processes showed organic recovery efficiencies ranging from 60 to 70 %. At a given recovery efficiency of 80 %, 17.3 % of energy potential ($1,398kJ/m^3$) is recovered through the anaerobic digestion and combustion of methane. Besides, anaerobic membrane bioreactor (AnMBR) can recover 85% of organic contents and generate $1,580kJ/m^3$ from the sewage. The recovered energy is equal to the amount of energy consumption by sewage treatment equipped with anaerobic ammonium oxidation (ANAMMOX)-based B-stage, $810{\sim}1,620kJ/m^3$. Therefore, it is possible to upgrade STPs as efficient as energy neutral. However, additional novel technologies, such as, fuel cell and co-digestion, should be applied to achieve "energy positive" sewage treatment.

• 한국막학회:학술대회논문집
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• 한국막학회 1998년도 제6회 하계 Workshop (98 한국막학회, 국립환경연구원 국제 Workshop, 수자원 보전과 막분리 공정)
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• pp.25-48
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• 1998

Current topics related to membrane technology under the recent water environment are as follows: - Cryptosporidum Outbreak - Integrity Control System - Water re-use - Recycle Society - Biotreatment and Membrane - Slurry or Sludge Treatment I would like to introduce the actual examples regarding water re-use. mainly on the above 5 topics.

• 한국물환경학회지
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• 제20권3호
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• pp.290-295
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• 2004

In this study, ozone was adopted for the reduction and stabilization of waste sludge from the municipal sewage treatment plant. The waste sludge used in the experiments was primary sludge, excess sludge and a mixture of the two. The sludge cells and flocs were disrupted by ozonation resulting in the reduction of TSS and VSS concentrations. In the case of the primary sludge with a concentration of 20 gTS/L, the TSS and VSS concentrations were reduced 28%, 33% and the TCOD concentration was reduced 20% respectively. The consumption of ozone was $0.18gO_3/gSS$. In the case of the excess sludge with a concentration of 7.5 gTS/L, the TSS and VSS concentrations were reduced 37%, 41%, and the TCOD concentration was reduced 19% respectively. The consumption of ozone was $0.33gO_3/gSS$. In the case of the mixed sludge of 9.3 gTS/L, the TSS and VSS concentrations were reduced by 45%, 53%, and the TCOD was reduced 26% respectively. The desirable consumption of ozone was $0.27gO_3/gSS$. As ozonation proceeded, the level of SCOD increased due to the release of intracellular materials. However TCOD was reduced due to mineralization resulting from the transformation of organic materials to inorganic materials.

• 한국지반환경공학회 논문집
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• 제17권8호
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• pp.5-15
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• 2016

국내 하수처리장의 증가 및 방류수 수질기준 강화 등에 따라 하수 슬러지의 발생량은 지속적으로 증가하는 추세이다. 기존 하수 슬러지는 소각과 해양배출 등으로 처리하였지만, 대기오염과 해양배출 금지 등에 따라 최근에는 자원화 또는 에너지화 방법 등을 연구하고 있다. 그러나 전반적인 기술의 수준 및 적용기술에 대한 체계적인 분석 등이 부족하여 관련 기술에 대한 향후 분석이 필요한 실정이다. 본 논문은 슬러지 처리기술, 고체연료화 및 바이오가스 증산 활용기술을 대상으로 관련 특허, 논문 동향을 조사하였다. 또한, 국내 외 연구개발 추이를 분야별 5개 국가별(한국, 일본, 중국, 미국, 유럽)로 조사 및 분석하였다. 향후 슬러지의 효과적 처리를 위해 필요한 기술 분야를 제시하였다.

• 한국환경농학회지
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• 제25권4호
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• pp.382-385
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• 2006

정수장슬러지의 수도육묘용 상토로서의 사용 가능성을 검토하기 위하여 정수장슬러지와 모래의 비율을 달리하는 상토들을 조제 후 시판용 상토를 대조로 수도유묘의 생육 및 무기성분흡수 특성을 조사하였다. 정수장슬러지 이용 상토는 시판용 상토에 비해 수도유묘 지상부의 신장 및 생중량이 다소 부진하고 인의 흡수량이 낮았던 반면, 지하부의 신장 및 생중량은 현저한 증가를 보여 정수장슬러지가 수도유묘의 뿌리발달에 탁월하고 뿌리의 매트형성이 우수하였다. 따라서 비록 정수장슬러지 이용 상토가 시판용 상토에 비해 수도유묘의 지상부 생장이 부진하고 인의 흡수가 다소 낮다 할지라도, 상토의 필수 조건인 뿌리의 매트형성이 탁월하고 단간의 지상부가 직립으로 매우 건실하며, 높은 pH에도 불구하고 입고병과 같은 병 발생이 없어 수도육묘용 상토로 이용 가능성이 높은 것으로 판단된다. 정수장슬러지 첨가에 따른 이러한 수도육묘의 뿌리생장 증가 효과는 정수장슬러지와 모래를 50:50 비율로 혼합한 상토에서 가장 우수하였다.

• 한국수자원학회논문집
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• 제35권2호
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• pp.213-220
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• 2002

하수 처리수의 재이용을 위하여 표준활성슬러지법에 의한 생물학적 처리 후 최종침전지 유출수를 급속여과공정으로 처리하기 위한 Pilot Plant 실험연구가 수행되었다. 또한, 활성슬러지와 연계된 급속여과공정과 포기조 후단에 응집제를 주입하는 활성슬러지 이후 급속여과 처리하는 공정과의 비교 실험도 행해졌다. 최종침전지 유출수를 급속여과공정으로 처리한 경우 여과속도는 100m/day, 여과지속시간은 40시간 이하로 운전하는 것이 타당한 것으로 나타났으며, 여과지의 역세척 주기는 여과속도 100m/day일 때 40시간에 1회 정도가 되었다. 여과지 역세척 시 역세척 방법은 공세 1분, 공세+수세 30초, 수세 1분, 공세·수세 2분, 수세 3분, 안정 30초, 배수 10분의 순으로 행하는 것이 효과적이었으며, 수세속도는 10LPM으로 전체 여과수량의 2%정도였다. 표준활성슬러지 시스템에 의한 2차 처리수를 잡용수로 재이용 하기 위해서는 폭기조 후단에 응집제를 첨가하여 여과 공정을 후속공정으로 하는 시스템으로 유용하게 사용할 수 있을 것으로 판단된다.

• 한국물환경학회지
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• 제21권2호
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• pp.158-168
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• 2005

In this study, the discharging effluents from have been 9 municipal wastewater treatment plants surveyed for 1 year-period. Statistics including probability distribution, cumulative occurrence concentration and other statistical parameters were presented. In addition, treatment performance and its stability were also discussed. Most of the plants, have an operational problem of high soluble organic content in the secondary effluent which may be associated with the integrated treatment of human and livestock manures. Nitrogen concentration in the effluents were usually higher during the period of summer and winter. It was found that this is mainly due to lack of the proper C/N ratio during the summer, or/and the effects of low temperature and less dilution by dry weather during the winter. Phosphorus concentration is sharply increased in June. Discussion with plant operators told that it is due to the dissolution of phosphate from the sludge accumulated in the primary settling tanks from the early spring to june. During this period, usually, sludge treatment line is highly overloaded with flush-outs of the sediments also stored in the bottom of combined sewer due to the low flow during winter season. Most of the plants can meet new effluent discharge limits of the nitrogen and phosphorus, and total coliform without further treatment.

• 한국기계가공학회지
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• 제21권9호
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• pp.35-41
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• 2022

The moisture content of many inorganic sludges is less than 70% during dewatering. Hence, a mono or piston pump cannot feed the sludge dryer. Thus, most inorganic sludge should be moved to a landfill or recycled directly without any reduction method. This development was invented to apply cyclone dryers using air and specially designed for the continuous injection of sludge sources by negative pressure and high air velocity for low moisture inorganic matter. Therefore, wastewater sludge and raw water treatment sludge discharged from various industrial fields might be settled by this development. The cyclone dryer was commercialized useful as moisture reduction equipment. This development was applied using a sludge injection system for sludge feeding and under the cooperation of ejector design computational fluid dynamics. Furthermore, this paper presented good ejector model results, blowing an airflow of 264 m³/min at an actual performance test.