• 한국대기환경학회지
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• 제22권1호
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• pp.25-33
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• 2006

The objective of this research is to improve the adsorption capacity of adsorbent made from MSWI (Municipal Solid Waste Incinerator) fly ash by surface oxidation. Used oxidation agents were $HNO_{3}$, $H_{2}SO_{4}$ and $(NH_{4})_{2}S_{2}O_{8}$. These agents can modify the surface property of an adsorbent such as specific surface area, pore volume, and functional group. The surface structure was studied by BET method with $N_{2}$ adsorption. The acid value and base value were determined by Boehm's method. The adsorption properties were investigated with benzene and MEK (Methylethylketone). According to the results, the specific surface area of the adsorbent was increased from 309.2 $m^{2}$/g to 553.2 $m^{2}$/g by $HNO_{3}$ oxidation. But $H_{2}SO_{4}$ and $(NH_{4})_{2}S_{2}O_{8}$ oxidation was decreased slightly. After Oxidation, surface acid value increased, but base value decreased. FAA-N shows the highest acid value. The content of oxygen increased greatly and oxygen group was created on the adsorbent surface. The surface oxidation improved the adsorbing capacity for MEK. The amount of adsorbing MEK was increased from 189 $m^{2}$/g to 639 $m^{2}$/g by $HNO_{3}$ oxidation.

• 한국지반환경공학회 논문집
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• 제10권5호
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• pp.33-39
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• 2009

본 연구는 정읍시에서 배출되는 하수 슬러지, 축산 분뇨, 음식물 쓰레기를 대상으로 Pilot Scale($100m^3$) 초고온 호기성 퇴비화 공정에서의 복합 악취 및 12개 지정 악취물질을 평가하였다. 각각의 대상 물질은 종균과 혼합하였고 1차 50일, 2차 60일 기간동안 운전하였다. 호기성 퇴비화가 진행됨에 따라 1차, 2차 퇴비화공정에서 온도가 상승하여 약 $90{\sim}95^{\circ}C$가 되었다. 악취 분석을 위한 시료는 1차의 경우 퇴비상부에서, 2차의 경우 Pilot Plant 경계지점에서 채취하였다. 지정 악취 물질 12개 항목의 기기 분석에서 악취의 주요 원인으로는 암모니아, 메틸머캅탄, 디메틸다이설파이드, 트리메틸아민이었다. 초기 복합악취의 농도는 퇴비화 공정이 끝난 후의 농도보다 높았지만 규제기준을 넘지 않았다. 초고온 호기성 퇴비화 공정에서는 적절한 교반시점과 발효 온도가 악취 발생의 중요한 인자라고 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제6권1호
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• pp.139-145
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• 1993

Biogas created from animal waste is a precious energy source. A practical and successful utilization of the biogas is not easy, because there lie some difficulties in biogas production and facilities investment. In this study, the requisites for a successful biogas utilization were discussed. The production results obtained in the previous operation of anaerobic digestion plant were used for the simulation. When the slurry heating was designed for constant biogas generation, depreciation costs of the facilities amounted 1,175,000 yen per year, and biogas productions at $24.5^{\circ}C$, $30.0^{\circ}C$ and $35.5^{\circ}C$ were $16.8m^3$, $17.6m^3$ and $25.1m^3$, respectively. Removal ratios of organic matters were not so high. At $35.5^{\circ}C$, energy value of the biogas produced was estimated 125.5 Mcal per day, and the following heat loss (y Mcal/day) was brought about by the temperature difference ($X^{\circ}C$) between the digester and atmosphere; y = 0.769X - 5.375. The costs of biogas production per cow were assumed to decrease according to enlargement of feeding scale, especially on scales of more than 30 cows. On recent levels of costs and prices of energy in Japan, they were nearly equal to 2 to 3 fold of the price of municipal mixed gas when a anaerobic digester was compulsorily heated and kept at $30.0^{\circ}C$ or $35.5^{\circ}C$.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.398-401
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• 2006

Two landfills of this study containing municipal wastes without any bottom liner and leachate treatment system have different landfill age, waste volume and most importantly different hydrogeologic settings. The one (Cheonan) is situated in an open flat area while the other (Wonju) is located in a valley. In the interior of the landfills, typical anaerobic conditions revealed by low DO and ${NO_3}^-$ concentrations, negative ORP values, high $NH_3$, alkalinity and $Cl^-$ concentrations were observed. Generally higher levels of contaminants were detected in the dry season while those were greatly lowered in the wet season. Significantly large decrease of Cl concentration in the wet season indicates that the dilution or mixing is one of dominant attenuation mechanisms of leachate. But detailed variation behaviors in the two landfills are largely different and they were most dependent on permeability of surface and subsurface layers. The intermediately permeable surface of 1.he landfills receives part of direct rainfall infiltration but most rainwater is lost to fast runoff. The practically impermeable surface of clayey silt (paddy field) at immediately adjacent to the Cheonan landfill boundary prevented direct rainwater infiltration and hence redox condition of the groundwaters were largely affected by that of the upper landfill and the less permeable materials beneath the paddy fields prohibited dispersion of the landfill leachate into downgradient area. In the Wonju landfill, there exist three different permeability divisions, the landfill region, the sandy open field and the paddy field. Roles of the landfill and paddy regions are very similar to those at the Cheonan. The very permeable sandy field receiving a large amount of rainwater infiltration plays a key role in controlling redox condition of the downgradient area and contaminant migration.

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 심포지움시리즈 Jan-97 수처리용 분리막 기술 및 응용
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• pp.55-62
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• 1997

In Japan, the membrane filtration is becoming a common technology for municipal water supply system especially for small plant. 6 years before (1991), the national research project of membrane filtration for small plant has started. The project was named as "MAC 21", MEMBRANE AQUA CENTURY 21. In the project the Ministry of Health and Welfare, 8 universities and 18 water treatment plant companies have been involved. This was the first attempt to research a common theme in joint with government, universities and private companies. After three years, the guide line for membrane filtration application for small plant has been established. This has promoted to install some actual plant. And also, another joint research for "RESEARCH OF MEMBRANE FILTRATION FOR ADVANCED WATER TREATMENT" has started in 1994 and completed in March, 1997. The project was named as MAC21. In the former project the main objectives were removal of turbidity and bacteria from water. However, in new project the objective was establishment of the further advanced membrane filtration technology which would be applicable for trace chemical components removal such as tri-halo-methane pre-courser, agricultural chemicals removal, offensive smell and taste removal and virus removal. For the objectives, application of nanofiltration and hybrid-system, a combination of micro-filtration ultra-filtration with biological, ozone and activated carbon treatment process have been studied. In addition, application of membrane filtration for treatment of back-wash waste water originated from membrane filters and conventional sand filters has.been studied. At the end of March of this year, about 30 membrane filtration plants are actually supplying the water, the total treatment capacity is about 6,000 m$^{3}$/day and another 20 will be installed within one year.led within one year.

• 분석과학
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• 제16권5호
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• pp.418-425
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• 2003

도시 생활폐기물의 소각로에서 발생되는 바닥재중의 무기원소 함량을 중성자 방사화분석법으로 결정하였다. D도시 소각장에서 월별로 채취한 바닥재 시료를 5 mm 크기의 체로 거르고 오븐에 건조한 후, 막자사발로 분쇄하였다. 시료는 한국원자력연구소의 하나로 연구용 원자로에서 NAA #1 조사공을 사용하여 중성자 조사하였으며, 조사된 시료는 HPGe-감마선 분광분석장치를 사용하여 방사능을 측정하였다. 측정된 핵종의 방사능으로부터 방사능 생성식과 핵 데이타를 적용하여 As, Cr, Cu, Fe, Mn, Sb 및 Zn을 포함한 33종의 원소를 정량하였다. 또한 미국표준기술원의 인증 표준물질을 동시에 분석하여 품질관리를 하였다.

• Environmental Engineering Research
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• 제11권4호
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• pp.217-231
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• 2006

The gas-phase formation of polychlorinated naphthalenes (PCNs) and dibenzofurans (PCDFs) was experimentally investigated by slow combustion of the three chlorophenols (CPs): 2-chlorophenol (2-CP), 3-chlorophenol (3-CP) and 4-chlorophenol (4-CP), in a laminar flow reactor over the range of 550 to $750^{\circ}C$ under oxidative condition. Contrary to the a priori hypothesis, different distributions of PCN isomers were produced from each CP. To explain the distributions of polychlorinated dibenzofuran (PCDF) and PCN congeners, a pathway is proposed that builds on published mechanisms of PCDF formation from chlorinated phenols and naphthalene formation from dihydrofulvalene. This pathway involves phenoxy radical coupling at unsubstituted ortho-carbon sites followed by CO elimination to produce dichloro-9, 10-dihydrofulvalene intermediates. Naphthalene products are formed by loss of H and/or Cl atoms and rearrangement. The degree of chlorination of naphthalene and dibenzofuran products decreased as temperature increased, and, on average, the naphthalene congeners were less chlorinated than the dibenzofuran congeners. PCDF isomers were found to be weakly dependent to temperature, suggesting that phenoxy radical coupling is a low activation energy process. Different PCN isomers, on the other hand, are formed by alternative fusion routes from the same phenoxy radical coupling intermediate. PCN isomer distributions were found to be more temperature sensitive, with selectivity to particular isomers decreasing with increasing temperature.

• 대한토목학회논문집
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• 제7권4호
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• pp.31-40
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• 1987

본(本) 연구(硏究)에서는 한국(韓國)의 도시(都市)에서 배출(排出)되어 매립(埋立)되는 고형폐기물중(固形廢棄物中) 약 40%를 차지하고 있는 유기성물질(有機性物質)로부터 biogas 생산(生産)에 대한 기초자료(基礎資料)를 얻기 위하여 광주시(光州市) 근교에 있는 매립장(埋立場)의 시료(試料)로서 1976년(年)부터 1985년(年)까지 연도별(年度別)로 함수율(含水率) 유기성물질함유율(有機性物質含有率)(VS)의 변화(變化)와 sacoharide계(系)와 lignin의 함량(含量) 변화(變化)를 측정(測定)하여 매립기간(埋立期間)의 경과에 따른 유기성물질(有機性物質)(VS)의 변화식(變化式)을 제안(提案)하였으며 sacoharide계(系)/lignin(S/L)로부터 매립(埋立)경과년수를 산정(算定)하는 방법(方法)을 수학적(數學的)으로 나타내었으며 S/L과 VS의 상관성(相關性)도 아울러 구하였다. 아울러 폐기물(廢棄物)의 종류별(種類別)로 분류(分類)한 시료(試料)와 혼합시료(混合試料)에 대한 가스 발생속도계수(發生速度係數)(k)를 구하여 도시폐기물(都市廢棄物)로부터 가스발생량(發生量)을 추정하는 수학적(數學的) 모형을 결정하였다.

• Carbon letters
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• 제18권
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• pp.49-55
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• 2016

Refuse-derived fuel (RDF) produced using municipal solid waste was pyrolyzed to produce RDF char. For the first time, the RDF char was used to remove aqueous copper, a representative heavy metal water pollutant. Activation of the RDF char using steam and KOH treatments was performed to change the specific surface area, pore volume, and the metal cation quantity of the char. N₂ sorption, Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES), and Fourier transform infrared spectroscopy were used to characterize the char. The optimum pH for copper removal was shown to be 5.5, and the steam-treated char displayed the best copper removal capability. Ion exchange between copper ions and alkali/alkaline metal cations was the most important mechanism of copper removal by RDF char, followed by adsorption on functional groups existing on the char surface. The copper adsorption behavior was represented well by a pseudo-second-order kinetics model and the Langmuir isotherm. The maximum copper removal capacity was determined to be 38.17 mg/g, which is larger than those of other low-cost char adsorbents reported previously.

• 대한환경공학회지
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• 제22권1호
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• pp.179-185
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• 2000

도시쓰레기 소각로에서 다이옥신류의 생성과 대기로의 방출을 최소화하기 위해 소각로의 후 연소 영역에서 다이옥신 전구물질의 원인이 되는 클로로페놀(이하 CP로 표기)의 거동에 대해 검토하였다. 전기관상로를 이용하여 온도조건 $300{\sim}500^{\circ}C$ 에서 CP을 주입하고 질소가스를 이용하여 반응시간을 조절하였으며 CP의 이성질체별 연소에 필요한 산소량은 계산된 실험식을 이용하여 주입하였다. 반응기내의 공간속도가 60~80/초의 조건에서 Mo-V계 촉매를 사용하여 촉매유무에 따른 CP의 분해 효율을 살펴보았다. 무촉매 열분해시 mono-CP은 74~80%, di-CP은 55~66%, tri-CP은 50~58%의 효율을 보였고, Mo-V계 촉매가 존재할 때 mono-CP은 90~99.9%, di-CP은 86~97%, tri-CP은 76~99%의 효율을 나타내 Mo-V계 촉매를 사용함으로써 약 20~30%의 효율이 증가함을 확인할 수 있다.