• Proceedings of the Korean Environmental Sciences Society Conference
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• 2016.10a
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• pp.208-208
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• 2016

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.1
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• pp.75-83
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• 2004

Temperature-phased anaerobic digestion (TPAD), anaerobic sequencing batch reactor (ASBR), and co-digestion technologies were combined together in order to overcome low efficiencies of conventional anaerobic sewage sludge digestion processes. In the performance, TPAD-ASBR process showed high VS removal efficiency over 60% up to the organic loading rate (OLR) of 2.7 g VS/L/d. The first-stage of TPAD-ASBR and control system played a most significant role in VS destruction and methane production. Methane production rate (0.79 l $CH_4/L/d$) of the system was higher than that (0.59 l $CH_4/L/d$) of the control system. The substrate characteristics of the sewage sludge, such as low VS concentration (1.5%, w/w) and biodegradability, were properly improved by the addition of food waste as a co-substrate, leading to more efficient VS removal and methane production. With several track studies, it was revealed that the independent solid retention time (SRT) of those systems prevented untreated particles from outflowing and also, extended the retention time of the active biomass for further degradation. Consequently, it was confirmed that the sequencing batch operation of the TPAD process using co-substrate was a promising alternative for the recycling of sewage sludge with low VS content.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.1
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• pp.52-64
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• 2002

유기성 폐기물을 이용하여 생물학적 수소생산 통합화 시스템 연구를 수행하였다. 통합화 시스템은 유기성폐기물의 전처리, 2단계 혐기발효 및 광합성 배양으로 구성된 생물학적 수소생산 공정, 초임계수 가스화 공정, 생산된 가스의 저장, 분리 및 연료전지를 이용한 전력 생산으로 구성되었다. 실험에 사용된 유기성 폐자원은 식품공장 폐수, 과일폐기물, 하수슬러지이며, 전처리는 폐기물에 따라 열처리 및 물리적 처리를 하였으며, 전처리된 시료는 생물학적 수소생산 공정에 직접 적용되었다. Clostridium butyricum 및 메탄 생성조에서 발생하는 하수슬러지중의 미생물 복합체는 수소생산 혐기 발효공정에 사용되었으며, 광합성 수소생산 미생물인 홍색 비유황 세균은 광합성 배양에 사용되었다. 생물학적 공정에서 발생하는 미생물 슬러지는 초임계수 가스화 공정으로 수소를 발생하였으며, 슬러지 중의 COD를 저하시켰다. 생물학적 공정 및 초임계수 가스화 공정에서 발생하는 수소는 가스탱크에 가입상태로 저장한 후, 95%순도로 분리하였으며, 정제된 수소는 연료전지에 연결하여 전력 생산을 하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.230-230
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• 2012

일본의 상하수도 사업은 국토교통성(하수도)과 후생노동성(상수도)으로 크게 양분되어 있으며, 환경성이 수질을 담당하는 체제로 이루어져 있다. 이는 수량과 수질을 분리하고 있는 우리나라와도 크게 다를 바가 없다. 그러나 중앙에서의 다원적인 분리와는 또 다른 차원으로 지방자치단체에서는 상하수도 통합이 급속도로 진행되고 있다. 이는 기후변화라는 지구적 환경의 변화와 더불어 해외 물산업에 대한 경쟁력이 밑바탕이 되면서 가속화되고 있다. 즉, 아시아의 신흥국을 중심으로 급격한 경제발전에 따른 인구가 증가하면서 정수장 및 하수처리장의 건설과 더불어 누수 및 도수(盜水) 문제가 현재화하면서 이에 대한 운영관리기술의 도입이 시급해졌기 때문이다. 이러한 과제를 해결할 수 있는 충분한 기술과 경험을 보유하고 있는 일본의 지방자치단체가 해외 물산업을 전제로 지자체 내의 상하수도 통합을 추진하고 있다. 본 연구는 이처럼 이원적으로 이루어지고 있는 일본 상하수도 업무의 법제도적 차이를 살펴보고, 특히 지자체를 중심으로 전개되고 있는 상하수도 통합과정의 동향과 의의를 풍중시((豊中市)토요나까시)의 사례를 중심으로 살펴보았다. 풍중시(豊中市)는 2008년 상하수도 통합을 천명하면서 기존의 운영방침에서 크게 탈각하는 정책을 취하게 되었고, 이 정책을 통하여 시의 지속가능한 발전 및 위기관리체제를 일신하고, 나아가 기후변화에의 대응력 강화에까지 그 범위를 확장하고 있다. 지자체의 상하수도 통합논의가 가속화되는 반면, 일본 중앙 정부에서는 아직 이렇다 할 움직임을 보이지는 않고 있다. 이는 부처간의 이견차이가 큰 부분인 만큼 쉽사리 제도적인 변경으로 움직이기는 어려울 것이다. 그러나 밑으로부터의 이러한 거대한 개혁움직임과 그 동인의 정당성을 확보해가고 있는 과정을 감안한다면 정부차원의 상하수도 통합이 완전히 부정되기도 어렵다. 상하수도 통합논의와 관련한 일본의 사례는 향후 우리나라 상하수도 정책을 재검토할 수 있는 계기가 될 것이다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.97-104
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• 2020

The present study conducted mock-up tests under the simulated sewage environments to examine the practical significance and limitation of coating materials that were previously developed on the basis of the bacterial glycocalix as a protection of concrete structures exposed to microbiological and sulphate attacks. The variations of the compressive strength and mass of the concrete due to the sulphate attack were measured using cylinder specimens. The bacteria growth and glycocalix formulation were calculated from the samples extracted from the sewage pipes. The next generation sequencing analysis was also conducted for environmental damage assessment due to the use of Rhodobacter capsulatus in the simulated sewage environments. The mock-up tests revealed that the developed coating materials have a good potential in resisting the sulphate attack, indicating no reduction on compressive strength and mass of the coated concrete under the sewage environment. At the age of 91 days, the concentrations of viable bacteria and glycocalix measured from the hardened coating materials were 1.4×10⁴cell/mL and 67.5mg/㎤, respectively. Moreover, harmful strains were not observed in the sewage water including glycocalix-coated concrete pipes. This implies that Rhodobacter capsulatus used in the coating materials does not influence negatively the microorganism cluster in the sewage environments.

• Water for future
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• v.15 no.2
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• pp.11-22
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• 1982

This study is to find out the reasonable drainage system of sewerage in connection with the geographical conditions, the form of city, and the problem of sewerage in and around Seoul. (1) In supplying the sewerage sewer, the separating system is desirable in connection with the problem of sewerage disposal in future. However, in the existing urban district, the conjunction system is used because of the large amount invested according to the diversion of the sewer of the separation system and the influence of the traffic communication. The sewer of the separating system should be used in the case of the fundamental reconstruction of structure as the redevelopment of the urban district or the subway and new-development of area. Therefore, the separating system should be used completely until the goal year. (2) Drainage area was divided for the natural flowing, considering that the 38 streams and topography paly a role of the main stream of drainage. There are the branches, Guyui, Dug-island, Jayang, Hannam, Banpo, Amsa whose divisions are impossible. In these branches, the drain planning was suggested a forced control method by using the exiting pond age and the pumping station. (3) The best available method which improbes the water quality in Han river is as follows. The sewerage is catched and carried to the sewerage disposal plant by establishing the intercept sewer in both or one side of stream. At the same time, the groudwater volume which springs in each stream is drained separatively.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.3
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• pp.38-45
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• 2008

There are still lots of areas where combined sewer pipes are covering in Seoul. All buildings within those areas are equipping septic tanks which take part in separating solids from flushing water of chamber pots. Septic tanks legally demand emptying and cleaning the those inner bodies once a year, resulting the generation of sludge which should be purified using the specified treatment plants as one of environmental infrastructures. Previous research showed that sludge volume continuously increase putting night soil treatment facilities in shortage by 3,549kL a day in 2020, which should be prepared by newly built facilities. This study aimed to define which process is more suitable especially in the points of cost and energy consumption. It was the main results that combining treatment of sewer with night soil, in fact same as nowaday process, is the very positive way beyond the treatment of night soil's own in respects of both costs and energy consumption.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.163-169
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• 2009

This study was performed to investigate the type of extended-spectrum $\beta$-lactamases (ESBL) produced by bacteria isolated from the sewage of wastewater treatment plant at Minragdong, Suyong-gu in Busan. The facility is located at sushi restaurants and guides its drain water to the wastewater treatment plant at Yonghodong, Nam-gu in Busan. Samples were collected on January, 2009. A total of 19 strains were selected as potential ESBL positive strains through a double disk synergy test. On the basis of the results from biochemical tests including indole, methyl-red, Voges-Proskauer, Simmon's citrate, decarboxylase-dihydrolase and sugar-fermentation tests, the 19 strains were identified with 16 strains of Escherichia coli and 3 strains of Klebsiella pneumoniae. Out of 19 strains, 4 transconjugants against Escherichia coli J53, which is sodium azide resistant recipient strain, were obtained. The plasmids isolated from transconjugants were used for PCR analysis. The type of each extended-spectrum $\beta$-lactamase (ESBL) produced by the strains was determined on the basis of isoelectric focusing analysis and DNA sequencing. The results indicated that the types of ESBL from Klebsiella pneumoniae were SHV-12 (3 strains), and Escherichia coli was SHV-12/TEM-1 (1 strain), respectively.

• Membrane Journal
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• v.12 no.3
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• pp.151-157
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• 2002

This research was to demonstrate the Possibility of sewage reuse for industrial purpose with use of membrane system. A bench scale test with microfiltration and reverse osmosis showed that microfiltration in the sewage treatment was not able to remove the soluble salts but 70% suspended solids (SS), suggesting that the treated water could be used as direct cooling water. In addition, the reverse osmosis removed not only soluble salts but also 95% SS, proposing that reverse osmosis-treated water could be used as both indirect cooling water and rinsing water. For a 100 ton/day pilot plant, 20 and 12 elements of microfiltration and reverse osmosis were required, respectively.

• Resources Recycling
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• v.6 no.1
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• pp.40-46
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• 1997

Sludgc d~sposal has been a major challenge in the wastewater treatment. Drying is operation which is separated fromsewage sludge to solid and liquid by heating. Drying needs to pretreatment process for effective "thation, incinerationand dispaal The objective of this work was to the drying dewatered sewage sludge by microwave heating, and tocompare the experimental rcsults with thcorctical rcsults. Microwave drylng is fast and has a high efficiency. In thepresent \ark, an unsteady state analysis of one dunensional drying, with microwave heating, is carried out. In drying ratecurve, moisture movement at falling rate period occured by dfision. A good agreement was abtamed between the modcland the experimental results using the slab sample of 0.2cm thickness. 0.2cm thickness.