• 한국환경보건학회지
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• 제40권6호
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• pp.477-483
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• 2014

Objectives: This study was carried out to investigate the characteristics of odors emitted from sewage in a sanitary sewer and its outlets. Methods: The concentration of mal-odorous sulfur was analyzed by gas chromatograph, and odor intensity was estimated by an on-site sensory test. Odor intensity calculated from instrumental analysis results was compared with odor intensity observed at field. Results: As a results, the concentration of $H_2S$ ranged from 2.4 ppb to 5,889 ppb (average 703 ppb), while $CH_3SH$, $(CH_3)_2S$, and $(CH_3)_2S_2$ showed from 10 ppb to 554 ppb (average 119 ppb) and from 20 ppb to 332 ppb (average 70 ppb) and from 2.7 ppb to 8.1 ppb (average 5 ppb) individually. Average odor intensity observed in the field was degree three. Odor intensity calculated from sulfur compound concentration was confirmed as similar to the observed odor intensity because the coefficient of variance between the observed and the calculated intensities was less than one. Conclusion: It was expected that the results of this study will be helpful to design a deodorizing device to reduce odor emissions from sewerage facilities in the future.

• Environmental Engineering Research
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• 제13권3호
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• pp.119-124
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• 2008

Ammonia is an inorganic compound that may cause severe odor problem. In this study the effectiveness of applying natural neutralizer to destroy and remove the odor-causing compound from gas streams was studied. Experimental result evaluated with a bench-scale apparatus via the neutralization of gas phase. This indicates that the natural neutralization depends on the gas concentration, gas residence time, temperature and pH. Removal efficiency of ammonia from gas stream was achieved by 95% using theconvection in the packed bed. This study proved the chemical neutralization technology was effective for controlling inorganic odor-causing compound.

• 센서학회지
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• 제24권1호
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• pp.29-34
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• 2015

This study aimed to evaluate the characterization of a metal oxide semiconductor and electrochemical gas sensor array for measuring wastewater odor. The sensitivity of all gas sensors observed in sampling method by stripping was 6.7 to 20.6 times higher than that by no stripping, except sensor D (electrochemical gas sensor). The average reduction ratio of sensor signal as a function of initial dilution rate of wastewater was in the order of food plant > food waste reutilization facility > plating plant. The sensitivity of gas sensors was dependent on both the type of wastewater and the dilution rate. The sensor signals observed by the gas sensor array were correlated with the dilution factor (OU) calculated by the air dilution sensory test with several wastewater ($r^2=0.920{\sim}0.997$), except the sensor signals of sensor D measured in the plating plant wastewater. It seems likely that the gas sensor array plays a role in the evaluation of odor in wastewater and is useful tool for on-site odor monitoring in the wastewater facilities.

• Journal of Biosystems Engineering
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• 제39권2호
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• pp.76-86
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• 2014

Purpose: The objective of this study was to measure emissions of gases (ammonia ($NH_3$), hydrogen sulfide ($H_2S$) and carbon dioxide ($CO_2$)), volatile organic compounds (VOC) and odor from two shallow pit pig nursery rooms. Gas and odor reduction practices for swine operations based on the literature were also discussed. Methods: This study was conducted for 60 days at a commercial swine nursery facility which consisted of four identical rooms with mechanical ventilations. Two rooms (room 1 (R1) and room 2 (R2)) with different pig numbers and ventilation rates were used in this study. The pig manure from both the R1 and R2 were characterized. Indoor/outdoor temperatures, ventilation rates/duration, $NH_3$, $H_2S$, $CO_2$, and VOC concentrations of the ventilation air were measured periodically (3-5 times/week). Odor concentrations of the ventilations were measured two times on two days. Three different types of gas and odor reduction practices (diet control, chemical method, and biological method) were discussed in this study. Results: The volatile solids to total solids ratio (VS/TS) and crude protein (CP) value of pig manure indicated the pig manure had high potential for gas and odor emissions. The $NH_3$, $H_2S$, $CO_2$ and VOC concentrations were measured in the ranges of 1.0-13.3, 0.1-5.7, 1600-3000 and 0.0-1.83 ppm, respectively. The $NH_3$ concentrations were found significantly higher than $H_2S$ concentrations for both rooms. The odor concentrations were measured in the range of $2853-4432OU_E/m^3$. There was significant difference in odor concentrations between the two rooms which was due to difference in pig numbers and ventilation duration. The literature studies showed that simultaneous use of dietary control and biofiltration practices will be more effective and environmentally friendly for gas and odor reductions from pig barns. Conclusions: The gas and odor concentrations measured in the ventilation air from the pig rooms indicate an acute need for using gas and odor mitigation technologies. Adopting diet control and biofiltration practices simultaneously could be the best option for mitigating gas and odor emissions from pig barns.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.247-251
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• 2005

This research was performed for developing of biological treatment process of odor gas such as MEK, $H_{2}S$, and toluene, which is generated from the food waste recycling process. To establish the operational conditions of odor gas removal by small-scale biofiltration equipment, it was continuously operated by using toluene as a treating odor object. When the odor treating microorganisms were adhered to fibril form biofilter, high removal efficiency over 93% was obtained by biofilm formation. At 400 ppm of inlet odor gas concentration and 10 sec of retention time, the removal efficiency was 76% and 93% in 1st stage reactor and 2nd stage reactor, respectively. However, the removal efficiency remained over 97% at the operational conditions above 15 sec of retention time.

• 상하수도학회지
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• 제27권3호
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• pp.373-382
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• 2013

In this study, a biological odor treatment system was proposed to remove odor(foul smell) materials causing several problems in the closed sewage treatment plant. This odor treatment system was composed of a two-step biofilter system in one reactor. The two-step biofilter reactor was constructed with natural purification layer in upper part and artificial purification layer in lower part. The reed grasses of water purification plants were planted in the surface area and mixed porous ceramic media were filled with the lower part of biofilter reactor. By using the above experimental apparatus, the ammonia gas removal efficiency was attained to 98.3 % and the hydrogen sulfide gas removal efficiency was appeared more than 97.7 % which shows more effective than the conventional odor removal process.

• 한국환경과학회지
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• 제11권4호
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• pp.383-389
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• 2002

Odor sources of a chemical plant in Ulsan were surveyed and temperatures, humidities and flow rates of each exhaust gas were measured. The air samples collected from each source were transferred to the laboratory for sensory test and their odor concentrations were investigated. The odor emission rate of each source was estimated from the recorded results and assigned the sources expected to be needed for the odor prevention policy using the simple prediction equation of the affection by malodor to the nearest residential area. From the total odor emission rate of the examined plant and the relation table for expectable affection area it was concluded that total odor emission of this plant might be decreased for the prevention of residential complaint.

• 대한환경공학회지
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• 제34권8호
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• pp.541-548
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• 2012

본 연구에서는 생활폐기물 자동집하시설에서의 악취물질 배출특성을 파악하고자 2개소(A시설, B시설)의 시설을 선정하여 공기관로 내의 이송가스와 최종배출가스를 대상으로 복합악취와 22종의 지정악취물질을 조사하였다. 생활폐기물 자동집하시설에서 배출되는 주된 악취물질은 암모니아, 황 화합물, 아세트알데하이드이었으며, 악취처리공정의 종류에 따라 최종배출구의 악취 배출특성이 상이하였다. 이송가스를 대상으로 한 악취기여도 평가에서는 A시설의 경우, 디메틸설파이드 26%, 아세트알데하이드 18%, 메틸머캅탄 14%의 악취기여도를 보였으며, B시설의 경우에는 메틸머캅탄 56%, 황화수소와 디메틸설파이드가 각각 15%이었다.

• 한국가스학회지
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• 제5권3호
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• pp.36-44
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• 2001

부취 농도가 낮을 경우 안전사고 발생의 우려가 있고, 과다 주입할 경우 주배관, 정압 설비 등의 수명 단축 및 환경오염의 문제를 야기 시킬 수 있다. 또한 부취제의 물성상 일정량이 배관 등에 물리$\cdot$화학흡착 또는 반응을 통하여 손실되어 적정 농도 유지에 어려움이 있고 비경제적이다. 따라서 부취제의 농도를 적정하게 유지하는 것은 매우 중요하다 본 연구에서는 배관내 부취제 농도의 적정관리를 위해 국내외 부취 설비와 농도관리현황, 소규모 설비의 특징과 장단점을 분석하였다. 또한 소규모 시스템의 적용시 운영방안과 타당성 분석을 제시하였다.

• The Korean Journal of Ceramics
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• 제6권3호
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• pp.304-308
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• 2000

WO$_3$/SnO$_2$ceramics has been suggested as an effective sensing material for monitoring offensive odor or pollutant gases. This work was focussed on improving long-term stability, which has been a principal problem generally taking place in SnO$_2$semiconductor gas sensor. Miniaturized thick film gas sensors were fabricated by screen printing technique. Two types of sensor materials, W doped SnO$_2$and WO$_3$mixed SnO$_2$, were comparatively investigated on those long-term stability and sensitivites to several gases. Small amount of W doping(0.1 mol%) into SnO$_2$largely improved the long-term stability. The W(0.1 mol%) doped SnO$_2$gas sensor had higher sensitivities to both acetone and alcohol compared with WO$_3$(5 wt%) mixed SnO$_2$gas sensor. On the contrary, WO$_3$(5 wt%) mixed SnO$_2$gas sensor showed more superior sensitivity to cigarette smoke due to larger W content.