• 자원리싸이클링
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• 제8권3호
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• pp.31-36
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• 1999

아크릴로니트릴 제조공정 중 부산물로 생성되는 물과 아세토니트릴 공비혼합물을 분비, 회수하기 위하여 혼합용매로서 toluene-ethylacetate를 선택하여 $25^{\circ}C$에서 4성분계 toluene(1)-water(2)-acetonitrile(3)-ethylacetate(4)에 대한 액-액평형 데이터를 구하였다. Tie-line 계산치를 예측하기 위하여 실험치를 UNIFA 모델식의 파라미터와 상호연관시켜 비교하였다. 또한 용매의 성능을 비교하기 위하여 분배계수 및 선택도를 고찰하였다.

• 한국응용과학기술학회지
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• 제22권4호
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• pp.379-384
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• 2005

In general, water treatment sludge (WTS) had high concentration of heavy metal, thus it made the reuse or recycling of WTS difficult. The optimal solidification conditions for maximum suppression of heavy metal elution from WTS were decided in this study. Under the optimal solidification conditions (i.e., temperature, $320^{\circ}C;$ ratio of WTS and MgO, 9:1; solidification time, 1hr), all of heavy metal including aluminum were not detected. Therefore there are no problems for reuse or recycling of WTS which was solidified under the optimal solidification conditions found in the study.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.561-568
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• 2002

PFA(Paper Fly Ash) are reclaimed mainly or used in cement industry field as mixture agent in terms of materials recycling. Recently, research for recycling PFA as embankment materials or soil stabilization agent are undergoing in geotechnical engineering field. In this study, physical characteristics of PFA stabilization agent-soil admixtures are examined in change of water content, void ratio, consistency, grain distribution, specific gravity and density. Futhermore, the physical characteristics are compared with unconfined strength as engineering characteristics. Test results showed that unconfined strength and density are increased with increasing of PFA stabilization agent mixed ratio. On the other hand, specific gravity, void ratio and water content are decreased with increasing of PFA stabilization agent mixed ratio. It would be concluded that natural high water content ratio weak soil could be highly improved engineering and physical characteristics with PFA stabilization agent

• 한국축산시설환경학회지
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• 제2권1호
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• pp.63-78
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• 1996

The main purpose of this research project is to monitor the present state of agricultural environment and to develope the countermeasures for the protection of the environment from the pollution by animal wastes. The results of this research were described largely 3 parts, 1) Monitoring of present state of environmental pollution by animal wastes, 2) Monitoring of animal wastes treatment technology, 3) Strategies for the protection of environmental pollution from animal wastes in future. The current most important problems from animal wastes are water pollution and air pollution commonly regardless of domestic or foreign country. Especially, intensive livestocks breeding pattern in restricted area is actually a real reason of eutrophication, soil acidification, ground water contamination, irrigation water pollution. As a result from this research project, authors recommend the 3 type of strategies for the protection of environmental pollution by animal wastes, 1 . Development of non-discharge type of wastes treatment technology 2. Manufacturing local structure for animal waste recycling system 3. Development of new international environmental program for transfer bioresource and soil environment prevention.

• 한국물환경학회지
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• 제25권3호
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• pp.404-410
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• 2009

In this study, research for physical and chemical characteristics were conducted through analysis of sediments, grading and heavy metals (e.g., Mn, Cu, Cd, Zn and Pb ) in sewers which are classified by drainage types. After that, cement solidification and yellow soil calcinations made heavy metals stabilized and then, ways of recycling it were examined. The grain size distribution of all sediments was relative graded. When evaluating heavy metal pollution through index of geoaccumulation (Igeo), Cu showed moderately pollution or strong pollution in forest and street site and Zn was assessed by moderately pollution in military, residential, and street site. Analysis of Pearson Correlation coefficient of heavy metal indicated that all items in street site have tight relationship respectively. Especially, Cd-Zn, Cu-Pb, Cu-Mn, and Pb-Mn have relationship at 99% confidence intervals in statistical analysis. Recycling it with cement solidification was satisfied with compressive strength standard under 55% deposit contents and Zn, Pb, Mn were stabilized effectively. If time and temperature plasticity and compressive strength would be standard, it is revealed that yellow soil calcinations is valuable aggregate when it has 50-60 Wt% contents. When considering economic feasibility and stabilization of heavy metals, cement solidification would be more appropriate than yellow soil calcinations as solution to recycling.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.192-199
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• 2010

This research produced internal model tester ($2.0m{\times}2.0m{\times}1.0m$) to evaluate the field application of Paju Unjeong District water recycling system for small streams eco-friendly river bed disparity method for the first time in Korea and conducted comparative analysis of the Paju Unjeong District water recycling system field test results and infiltration rate result of internal tests by each rainfall intensity following surface material. Infiltration rate result of internal tests concrete pavement by rainfall intensity following surface material, asphalt pavement, bentonite mate, stabilized soil construction and mixed soil construction manifested low infiltration rate. On the contrary, compaction soil, grassland and water permeable packaging materials resulted in significant amount of infiltration rate. As for the field permeability test results, they were manifested similar tendency as indoor permeability test results and they satisfied the standard for standard of water permeability of domestic disparity facility (less than $1.0{\times}10-7cm$/sec). As compaction rate increased, unconfined compression strength increased as well while coefficient of water permeability decreased.

• 청정기술
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• 제7권4호
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• pp.225-242
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• 2001

산업체에서 부품을 가공하거나 완성품을 제조하는 과정에서 세정 공정은 필수적으로 사용하고 있고 현재 국내외 대부분의 제조업체에서는 오존파괴물질인 CFC-113이나 1,1,1-TCE 대신에 보다 환경친화적인 수계 세정제로의 대체가 진행중이다. 그러나 수계 세정시스템은 세정공정이나 헹굼공정에서 다량의 물을 사용하기 때문에 많은 폐수를 발생시키는 단점이 있다. 따라서 수계 세정시스템에서는 이러한 발생을 최소화하고 세정액과 헹굼수의 성능을 오랫동안 유지시키기 위한 모니터링 기술과 재활용 기술의 도입이 긴요하다. 본고에서는 수계 세정시스템에 사용하는 세정제와 주요 오염물질인 절삭유를 조사 분석하였고 산업현장에서 도입 가능한 수계 세정시스템의 모니터링 기술과 재활용 기술 등을 분석 평가하였다.

• 한국건설순환자원학회논문집
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• 제9권1호
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• pp.92-99
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• 2021

CaO 화합물의 원료로는 일반적으로 CaO, SO3, Al2O3 등으로 구성된 CaO 기반인 산업부산물이 있다. 이러한 CaO 계 산업부산물을 레미콘의 회수수에 적용할 경우 시멘트, 플라이애시, 슬래그미분말 등의 콘크리트 분말 원료의 수화 반응이 가속화되어 콘크리트 성능을 향상시킬 수 있다. 본 연구에서는 레미콘의 회수수에 C12A7을 함유한 열연 슬래그를 혼입하여 레미콘의 회수수에 적용할 수 있는 활성슬러지를 제조하였으며, 시멘트 페이스트 응결시간 및 모르타르 압축강도 성능 테스트를 통해 수화반응에 대한 영향을 확인하고자 하였다.

• 한국건설순환자원학회논문집
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• 제10권1호
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• pp.48-55
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• 2022

본 연구는 콘크리트의 운반 과정 중 발생하는 레미콘 회수수의 재활용율 증대 및 온실가스 저감을 위한 연구의 일환으로 회수수를 배합수 및 인공경량골재 프리웨팅수로 사용하고 고로슬래그 미분말 및 플라이애시를 시멘트 대체재로 사용한 3성분계 경량 골재 모르타르의 공학적 특성을 검토하였다. 이를 위해 3성분계 경량 골재 모르타르의 플로우, 기건단위질량, 압축강도, 건조수축, 중성화 깊이, 염화물 이온 침투 저항성을 측정하였으며 측정 결과 회수수를 사용할 경우 높아진 알칼리도에 의해 시멘트계 재료들의 반응성이 높아졌으며 3성분계 배합과 함께 사용할 경우 고로슬래그 미분말 15 %, 플라이애시를 5 % 사용할 시 모르타르의 압축강도 및 내구특성 향상에 긍정적인 것으로 나타났다.

• 한국환경보건학회지
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• 제45권3호
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• pp.222-230
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• 2019

Objectives: This study aims to evaluate water quality in terms of microorganisms and identify the antibiotic resistance of Enterococci isolated from the recycling water in floor fountains at three parks and one reservoir in the Gwangju area. Methods: Water samples were analyzed for Enterococci using membrane Enterococcus indoxyl ${\beta}$ d glucoside agar (mEI) as described in USEPA Method 1600. The vancomycin-resistant Enterococci with VanA and VanB were identified by PCR. An examination of the antibiotic resistance of isolates against 14 antibiotics was performed by the disk diffusion method. Results: The drinking water quality criterion was exceeded for total colony counts in 68% of all recycling water samples. The average concentration of total califorms and fecal coliforms was 139,325 and 413 CFU/100 mL, respectively. VanA and VanB were not detected from the isolates. We found the antibiotic resistant Enterococci strains to be E. faecalis, E. faecium, E. durans, E. mundtii, E. hirae, and E. thailandicus. The isolates were resistant to Rifampin (50%), Erythromycin (25.8%), Tetracycline (10.2%), Nitrofurantoin (8.1%), Minocycline (3.1%), Erythromycin (1.2%), Penicillin (0.7%), Norfloxacin (0.5%), and Teicoplanin (0.5%) among the 14 antibiotics tested. Antibiotic resistance tests for Enterococci from the recycling water of floor fountains resulted in 30.2% showing resistance to two or more antibiotics. Conclusions: These results showed that the multi-antibiotic resistance of Enterococci, E. coli, and others should be investigated continuously in each environment field.