• 한국산업보건학회지
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• 제29권3호
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• pp.404-413
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• 2019

Objectives: Chronic obstructive pulmonary disease(COPD) is an important cause of mortality in workers exposed to hazardous dust, such as crystalline silica or coal, and COPD is related to inflammation and oxidative stress in the lung. The aim of this study was to evaluate the association of oxidative stress and inflammation to COPD in retired workers exposed to mineral dust. Methods: The levels of malondialdehyde(MDA) in EBC as biomarkers for oxidative stress and C-reactive protein(CRP) and lactate dehydrogenase(LD) as biomarkers for inflammation were measured in 107 male subjects(63 pneumoconiosis and 42 COPD subjects). Results: Mean levels of EBC MDA(2.03 nmol/L vs. 4.65 nmol/L, p=0.010) and serum LD(170.3 U/L vs. 185.9 U/L, p=0.022) were significantly higher in subjects with COPD, but mean levels of serum CRP(p=0.469) did not show a statistical difference between the study groups. Level of EBC MDA was negatively correlated with ${%}FEV_1$ predicted(r=-0.279, p=0.004) and ${%}FEV_1/FVC$ ratio(r=-0.397, p<0.001). Conclusions: These results suggest that EBC is a useful biological matrix for investigation of respiratory oxidative stress. High levels of EBC MDA and serum LD are related to COPD in retired workers exposed to mineral dust.

• 대한환경공학회지
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• 제39권8호
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• pp.449-455
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• 2017

기준공정과 개선대상공정 간의 투입물(Input, Material and energy), 배출물(Output, Product, Co-product), 환경오염물(Environmental emission) 데이터를 수집하고 공정 성과를 분석하였다. 이를 통해 환경적으로 주요한 투입물과 환경오염물을 파악하였다. 제조공정의 투입물과 환경오염물 간의 상관관계 분석을 통해 각 환경오염물에 대한 기여도가 큰 투입물을 파악하였다. 주요 환경오염물 처리 시, 경제적 최적화를 통한 종말처리공정 조합을 선형 프로그래밍 기법을 사용하여 규명하였다. 사례 연구로는 동일한 형태의 시멘트를 생산하는 EU와 국내 시멘트 제조공정을 선정하였다. 국내 시멘트 제조공정에서는 석탄이 주요 투입물로, 먼지, $SO_x$가 주요 환경오염물로 파악되었다. 제조공정의 투입물과 환경오염물 간의 다중회귀분석결과 석탄>원자재>석고 순으로 $CO_2$발생량에 기여도가 큰 것으로 나타났다. $SO_x$발생량의 경우 석탄의 기여도가 가장 컸으며, Dust 발생량의 경우 석고>원자재 순으로 기여도가 큰 것으로 나타났다. Dust 종말처리공정 최적화에서 전기집진기술 100%, 섬유필터기술 2.4% 조합이 최적이었다. $SO_x$종말처리공정 최적화에서는 건식첨가공정기술 100% 습식세정기술 25.88% 조합이 최적이었다. 이 연구의 특징은 제조공정에서 문제가 되는 주요 투입물과 환경오염물을 파악하는 방법을 제시하였다는 점이다. 또한, 기술적 경제적으로 최적의 조합인 종말처리공정 선정 방법을 제시하였다는 점이다.

• Tuberculosis and Respiratory Diseases
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• 제50권1호
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• pp.76-83
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• 2001

연구배경 : 탄광부 진폐증은 석탄 분진의 흡입에 의한 폐조직의 손상에 대하여 부적절하고 과도한 염증반응이 일어나 폐섬유화를 유발하여 발병하는 것으로 생각되어지고 있다. 이 반응에는 대식세포를 비롯한 많은 염증세포들과 그 세포들에서 분비되는 매개물질들이 중요한 역할을 한다. TGF-$\beta$는 특발성 폐섬유화증, 규폐증 및 석면증의 폐섬유화 과정에 관여한다고 알려져 있다. 그러나 비슷한 기전에 의해 폐 섬유화가 진행되는 것으로 생각되는 탄광부 진폐증에서는 TGF-$\beta$의 관여여부에 대한 보고가 거의 없다. 본 연구는 탄광부 진폐증 환자에서 혈청 TGF-${\beta}_1$을 측정하여 섬유화의 정도에 따른 그 활성도의 변화를 비교하여 탄광부 진폐증의 폐섬유화 과정에 TGF-${\beta}_1$이 관여하는지 알아 보고자 하였다. 방법 : 직업력과 방사선학적 소견 상 탄광부 진폐증으로 진단 된 환자 중 단순 탄광부 진폐증 20예와 복잡성 탄광부 진폐증 20예를 대상으로 하였다. 정상소견인 자 10명을 대조군으로 설정하였으며, 각 대상을 human TGF-${\beta}_1$ immunoassay kit (R&D system, Minneapolis, MN)을 이용하여 혈장 내 TGF-${\beta}_1$을 측정하였다. 결과 : 단순 탄광부 진폐증($0.64{\pm}0.17$ ng/mL)과 정상 대조군($0.63{\pm}0.18$ ng/mL)보다 복잡성 탄광부 진폐증 ($0.79{\pm}0.18$ ng/mL)의 혈중 TGF-${\beta}_1$의 농도가 의미 있게 높았다(p<0.05). 결론 : 탄광부 진폐증의 섬유화 진행 과정에 TGF-${\beta}_1$이 관여함을 알 수 있었다. 따라서 단순 탄광부 진폐증과 복잡성 탄광부 진폐증의 감별진단과 경과 예측인자로서 혈장 TGF-${\beta}_1$이 유용하리라 생각되며, TGF-${\beta}$의 생성을 억제한다면 탄광부 진폐증의 섬유화 진행을 저지함으로써 탄광부 진폐증의 치료에 있어 중요한 역할을 할 수 있을 것으로 기대된다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2009년도 추계학술발표논문집
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• pp.263-266
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• 2009

석탄광산의 선탄장(選炭場)에서 운용하는 장치들로부터 발생하는 석탄분진의 입도분포를 현장조사와 실내분석을 통하여 파악하였으며, 연구결과는 광해(鑛害)로서 작용하는 석탄분진을 포집하는 집진기(A Dust Collector)의 설계에 필요한 자료로 제시하고자 한다. 연구결과 TB업체의 분진 입도분포는 $1{\mu}m$이하의 미세(微細)입자와 $100{\mu}m$이상의 조대(粗大)입자가 차지하는 비중이 미약한 반면, 특히 $5{\mu}m{\sim}80{\mu}m$ 사이에 분포되는 분진들이 89.2%로 나타나 발생분진의 대부분을 차지하는 것으로 파악되었다. 이들 중 원심집진기에 포집된 분진은 $70{\mu}m$이하에서 89.5%인 반면 여과집진기에서 포집된 분진의 90.0%가 $20{\mu}m$이하인 것으로 나타났다. SD업체의 분진 또한 $1{\mu}m$이하와 $100{\mu}m$이상 입자는 적은 분포를 보인 반면, $5{\mu}m{\sim}70{\mu}m$사이에 분포되는 분진들이 89.6%로 나타나 발생분진의 대부분을 차지하는 것으로 파악되었다. 이들 중 여과집진기에 포집된 분진의 입도는 $30{\mu}m$이하에서 96.2%인 것으로 나타났다.

• 대한기계학회논문집B
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• 제20권5호
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• pp.1639-1648
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• 1996

Protection of gas turbine blade from its erosion and abrasion at high temperature and pressure is the first goal to cleanup the hot gas upstream for IGCC and PFBC. Ceramic filters represent an attractive technology for particle removal at high temperature and high pressure condition. They have demonstrated being a good system for improvement of thermal efficiency and reduction of effluent pollutants in advanced coal-based power systems such as IGCC and PFBC. Ceramic filter elements currently being developed were evaluated in the previous paper. In this paper, we measured the ash size and distribution on cleaning of ceramic candle filter. The results are as follows : in this experimental range, ceramic candle filter was shown to be fully adequate for the removal process of dust under high temperature and pressure. Also filtration efficiency of ceramic candle filter was higher than 98% compared with the regulation limit of particle size in gas turbine inlet.

• 자원환경지질
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• 제25권3호
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• pp.317-336
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• 1992

The garden soils, main road dusts, residential road dusts, and playground soils/dusts of Seoul, Geumsan, Onsan, and Taebaek areas were analyzed in order to investigate the level of heavy metal pollution by urbanization and industrialization. The soil pH is in the range of 5.48~8.40 and was generally neutral. The color of soils and dusts is mainly Raw Umber to dark greyish Raw Umber. Some samples from Taebaek city, a coal mining area, showed a deep black color due to contamination by coal dusts. Major minerals of the dusts and soils are quartz, feldspars, and micas, reflecting the composition of the parent rocks. However, pyrite was found as a major mineral in the samples of industrial road dusts of Onsan, a smelting area, and resicential road dusts of Taebaek. Thus, the high level of heavy metals in mining and smelting areas can be explained with the sulfide minerals. The mode of occurences of heavy metals in Seoul, a comprehensive urbanized area, were related to the metallic pollutants and organic materials through observation by scanning eletron microscopy. In main road and residential road dusts of Onsan area, Cd, Zn, and Cu were extremely high. Some industrial road and residential road dusts of Seoul area showed high Cu, Zn, and Pb contents, wereas some garden soils and residential road dusts of Taebaek area were high in As content. In general, the heavy metal contents in dust samples were two to three times higher than those in soil samples. Main road dust samples were the most reflective from the discriminant analysis of multi-element data. Cadmium, Sb, and Se in Onsan area, As in Taebaek area, Pb and Te in Seoul area were most characteristic in discriminating the studied areas. Therefore, Cd in smelting areas, As in coal mining areas, and Pb in metropolitan areas can be suggested as the characteristic elements of each pollution pattern. The dispersion of heavy metal elements in urban areas tends to orignate in main roads and deposit in garden soils through the atmosphere and residential roads. The heavy metal contamination in Seoul is characteristic in areas with high population, factory, road, and traffic decsities. Heavy metal contents are high in the vicinity of smelters in Onsan area and are decayed to background levels from one kilometer away from the smelters.

• 한국건설순환자원학회논문집
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• 제5권3호
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• pp.305-312
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• 2017

본 연구에서는 국내 화력발전소에서 발생되고 있는 산업부산물을 활용하여 아스팔트 콘크리트용 채움재를 개발 및 혼합물에 적용하여 함량에 따른 특성 및 소성변형 저항성에 미치는 영향을 관찰하였다. 실험결과 석탄회 기반 채움재를 사용할 경우 최적아스팔트함량(OAC)는 기존 채움재 대비 0.1% 낮은 값을 나타내었다. 도출된 최적아스팔트함량에서 채움재 함량에 따른 간접인장강도 및 인장강도비 측정 결과 함량 증가에 따라 높은 성능을 발현하였고, 2.0% 이상의 함량에서 국내 단체표준 품질관리 기준 각 0.8 이상과 0.75 이상을 만족하는 결과를 얻을 수 있었다. 동적안정도는 채움재 2.5%의 함량에서 가장 높은 저항성을 나타내었으며, 함량이 2.5%를 넘어설 때 오히려 성능발현이 저하되는 결과를 나타내었다. 과도한 채움재의 혼입은 상대적으로 아스팔트 함량이 감소되기 때문에 취성파괴를 유발할 수 있으므로 최적의 채움재/아스팔트 의 비율을 찾아 적용하는 방안이 필요할 것으로 판단된다.

• Safety and Health at Work
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• 제5권2호
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• pp.91-96
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• 2014

Background: Chronic obstructive pulmonary disease (COPD) is an important cause of occupational mortality in miners exposed to coal mine dust. Although the inflammatory mediators involved in COPD have not been defined, many studies have shown that inflammatory mediators such as reactive oxygen and nitrogen species are involved in orchestrating the complex inflammatory process in COPD. Methods: To investigate the relevance of exhaled biomarkers of oxidative and nitrosative stress in participants with COPD, we determined the levels of hydrogen peroxide, malondialdehyde (MDA), and 3-nitrotyrosine (3-NT) in exhaled breath condensate (EBC) in 90 retired elderly coal miners (53 non-COPD and 37 COPD participants). Results: Mean levels of MDA (4.64 nMvs. 6.46 nM, p = 0.005) and 3-NT (3.51 nMvs. 5.50 nM, p = 0.039) in EBC were significantly higher in participants with COPD. The median level of MDA did show statistical difference among the COPD severities (p = 0.017), and the area under the receiver operating characteristic curve forMDA (0.67) for the diagnostic discrimination of COPD indicated the biomarker. The optimal cutoff values were 5.34 nM (64.9% sensitivity and 64.2% specificity) and 5.58 nM (62.2% sensitivity and 62.3% specificity) forMDA and 3-NT, respectively. The results suggest that high levels ofMDA and 3-NT in EBC are associated with COPD in retired elderly miners. Conclusion: These results showed that the elevated levels of EBC MDA and EBC 3-NT in individuals with COPD are biomarkers of oxidative or nitrosative stress.

• 한국입자에어로졸학회지
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• 제15권3호
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• pp.105-113
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• 2019

The exhaust emissions from coal-fired power plants have received much attention because coal-fired power plants are the one of the largest sources of particulate matter (PM) emissions in South Korea. To measure the PM10 and PM2.5, we developed the novel diluter which is comprised of ejector and porous tube in series. The dilution ratio must be defined to calculate particle concentrations of the sampled air as well as to probe match for the isokinetic sampling. For this reason, we verified the dilution ratio of the developed diluter by the flow rate, numerical solution, gas concentration and particle concentration. The ejector-supplied flow rates were 10-50 L/min and the porous tube-supplied flow rates were 30, 50 L/min in this study. All methods above showed similar dilution ratios to each other within 10 % error rate. The dilution ratio was confirmed by comparing mass concentrations before and after the dilution process.

• KEPCO Journal on Electric Power and Energy
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• 제6권4호
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• pp.455-460
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• 2020

In order to identify the characteristics of fine particle emissions from thermal power plants, this study conducted measurement of the primary emission concentration of TPM, PM₁₀ and PM_2.5 according to Korea standard test method (ES 01301.1) and ISO 23210 method (KS I ISO 23210). Particulate matters were sampled in total 74 units of power plants such as 59 units of coal-fired power plants, 7 units of heavy oil power plants, 2 units of biomass power plant, and 6 units of liquid natural gas power plants. The average concentration of TPM, PM₁₀, PM_2.5 by fuel are 3.33 mg/m³, 3.01 mg/m³, 2.70 mg/m³ in coal-fired plant, 3.02 mg/m³, 2.99 mg/m³, 2.93 mg/m³ in heavy oil plant, 0.114 mg/m³, 0.046 mg/m³, 0.036 mg/m³ in LNG plant, respectively. These results of TPM, PM₁₀ and PM_2.5 were satisfied with the standards of fine dust emission allowance in all units of power plants, respectively. Also, this study evaluated the characteristics of fine particle emissions by conditions of power plants including generation sources, boiler types and operation years and calculated emission factors and then evaluated fine particle emissions by sources of electricity generation.