• 유기물자원화
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• 제8권1호
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• pp.103-108
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• 2000

2001년부터 정수장에서 발생하는 유기성오니의 직매립이 금지됨에 따라 이의 처리비용이 매우 증가할 것으로 판단되어 본 연구에서는 정수장 슬러지를 Chemical 및 Hydrothermal법을 사용하여 농업 및 임업용 비료로 재활용 할 수 있는 방법을 찾고자 진행하였고, 그 결과 두 방법 모두 유기물 및 유해 중금속을 제거할 수 있었으며 안정화된 무기질 비료를 제조할 수 있었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1463-1474
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• 2008

In order to investigate stabilization effect and sustainability on As-contaminated farmland soils which were affected the abandoned mine site and stabilized by zerovalent iron(ZVI) and industrial by-products, batch-scale and pilot-scale tests were carried out. In batch tests, ZVI and industrial by-products(blast furnace slag, steel refining slag and oyster shell powder) were used in treatment materials to reduce the As leaching. Industrial by-products were mixed with As-contaminated soils, in the ratio of 1%, 3%, 5% and 7% on the weight base of dried soil. The results of batch-scale tests was shown that the reduction of As concentration was observed in all samples and it was expected that ZVI and steel refining slag were more effective than other treatment materials to stabilize As compounds. In pilot-scale tests, columns were filled with untreated soils and treated soils mixed with ZVI and steel refining slag in the same mixing ratio of 3%. Distilled water was discharged into the columns with the velocity of 0.3 pore volume/day. During the test, pH, EC, Eh and As concentration were measured in the regular term(1pore volume). after six months, pilot-scale tests were retested to investigate sustainability of treatment materials. As a result, It was shown that the leachate from control column was continuously released during the test period and its concentration was greater than $100ug{\cdot}L^{-1}$ which was exceeded the national regulation of water discharged to river or stream ($50ug{\cdot}L^{-1}$). On the other hand, soil treated with ZVI and steel refining slag showed that the concentrations of leachate were lower than national regulation of water discharged to river or stream. Therefore it was expected that ZVI and steel refining slag could be applied to the farmland site as the alternative treatment materials.

• Safety and Health at Work
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• 제14권3호
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• pp.279-286
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• 2023

Background: This study aimed to evaluate the association between exposure to occupational hazards and the metabolic syndrome. A secondary objective was to analyze the additive and multiplicative effects of exposure to risk factors. Methods: This retrospective cohort was based on 31,615 health examinees at the Pusan National University Yangsan Hospital in Republic of Korea from 2012-2021. Demographic and behavior-related risk factors were treated as confounding factors, whereas three physical factors, 19 organic solvents and aerosols, and 13 metals and dust were considered occupational risk factors. Time-dependent Cox regression analysis was used to calculate hazard ratios. Results: The risk of metabolic syndrome was significantly higher in night shift workers (hazard ratio = 1.45: 95% confidence interval = 1.36-1.54) and workers who were exposed to noise (1.15:1.07-1.24). Exposure to some other risk factors was also significantly associated with a higher risk of metabolic syndrome. They were dimethylformamide, acetonitrile, trichloroethylene, xylene, styrene, toluene, dichloromethane, copper, antimony, lead, copper, iron, welding fume, and manganese. Among the 28 significant pairs, 19 exhibited both positive additive and multiplicative effects. Conclusions: Exposure to single or combined occupational risk factors may increase the risk of developing metabolic syndrome. Working conditions should be monitored and improved to reduce exposure to occupational hazards and prevent the development of the metabolic syndrome.

• 한국토양비료학회지
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• 제43권3호
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• pp.283-288
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• 2010

화산회토양에서 돈분퇴비 연용이 감자재배 토양의 토양화학성과 탈수소 효소활성 및 감자수량에 미치는 영향을 평가하고자 수행 하였다. 돈분퇴비 시용량이 증가할수록 점차적으로 토양 pH, 토양질소, Avail.-Phosphate, Exch.-K, Exch.-Ca, Exch.-Mg, Zn, Cu 함량이 증가하였다. 돈분퇴비 시용량이 많고 작기가 많아질수록 토양 탈수소효소활성은 증가하였다. 3작기 후 Dehydrogenase활성은 돈분퇴비 2톤구 3.5, 4톤구 6.3, 6톤구 8.0 ug TPF $g^{-1}\;24h^{-1}$를 나타냈으며 1작기 후 보다 2배 이상 증가하였다. 3작기 동안 Cu와 Zn함량이 증가함에 따라 dehydrogenase활성이 직선적으로 증가하였으며 Cu는 $R^2$=0.907, Zn은 $R^2$=0.859의 상관관계를 나타냈다. 돈분퇴비 시용량이 많을수록 감자수량은 증가하였으나 표준시비+돈분퇴비 2톤구에서 가장 많았다.