• 제목/요약/키워드: Reduction efficiency

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돈사용 스크러버 및 바이오커튼의 축산악취 저감효과 분석 (Evaluation of Livestock Odor Reduction Efficiency for Odor Reduction Systems in Domestic Pig Farms)

  • 이민형;여욱현;이인복;정득영;이상연;김준규;크리스티나;최영배;강솔뫼
    • 한국농공학회논문집
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    • 제64권6호
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    • pp.77-86
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    • 2022
  • Various odor reduction systems are being operated at pig houses to improve livestock odor issues. However, the quantitative evaluation of odor reduction efficiency is not sufficiently conducted. The analysis of factors that affect the reduction efficiency also has not been sufficiently conducted. Therefore, in this study, the reduction efficiency of representative odor reduction facilities (bio-curtain, scrubber) operated by domestic pig houses was evaluated. The odor reduction efficiency was evaluated by sampling the air before and after the odor reduction facility in 6 pig houses. Livestock odors were evaluated for complex odors, ammonia, hydrogen sulfide, and VOC. To find factors for reduction efficiency, temperature, humidity, pH of washing resolution, type of washing water, and ventilation rate was measured. As a result, it was found that the scrubber system had the highest reduction efficiency. The reduction efficiency was found to be affected by the scrubber's washing resolution, filler, operating conditions, and size. Bio-curtains may have problems such as deterioration of fan performance due to ventilation fan load, groundwater pollution, and excessive use of groundwater.

Evaluation of Green House Gases (GHGs) Reduction Plan in Combination with Air Pollutants Reduction in Busan Metropolitan City in Korea

  • Cheong, Jang-Pyo;Kim, Chul-Han;Chang, Jae-Soo
    • Asian Journal of Atmospheric Environment
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    • 제5권4호
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    • pp.228-236
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    • 2011
  • Since most Green House Gases (GHGs) and air pollutants are generated from the same sources, it will be cost-effective to develop a GHGs reduction plan in combination with simultaneous removal of air pollutants. However, effects on air pollutants reduction according to implementing any GHG abatement plans have been rarely studied. Reflecting simultaneous removal of air pollutants along with the GHGs emission reduction, this study investigated relative cost effectiveness among GHGs reduction action plans in Busan Metropolitan City. We employed the Data Envelopment Analysis (DEA), a methodology that evaluates relative efficiency of decision-making units (DMUs) producing multiple outputs with multiple inputs, for the investigation. Assigning each GHGs reduction action plan to a DMU, implementation cost of each GHGs reduction action plan to an input, and reduction potential of GHGs and air pollutants by each GHGs reduction action plan to an output, we calculated efficiency scores for each GHGs reduction action plan. When the simultaneous removal of air pollutants with the GHGs reduction were considered, green house supply-insulation improvement and intelligent transportation system (ITS) projects had high efficiency scores for cost-positive action plans. For cost-negative action plans, green start network formation and running, and daily car use control program had high efficiency scores. When only the GHGs reduction was considered, project priority orders based on efficiency scores were somewhat different from those when both the removal of air pollutants and GHGs reduction were considered at the same time. The expected action plan priority difference is attributed to great difference of air pollutants reduction potential according to types of energy sources to be reduced.

저녹스 버너 설치 시설의 질소산화물 저감 효율 산정 방법 (The Methods Calculating the Reduction Efficiency of Nitrogen Oxide for the Facilities Including the Low NOx Burners)

  • 이기용
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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    • pp.295-296
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    • 2015
  • We presented the methods calculating the reduction efficiency of nitrogen oxide for the low $NO_x$ burner as the pollution prevention facilities. The standard $NO_x$ concentration was used on the emission factor of LNG, $3.7g/m^3$. The $NO_x$ reduction efficiency based on the $NO_x$ concentration was presented and the relationships between the $NO_x$ concentration and the emission factor or the specific heat emission factor were derived. These results could be accurately reflected on calculating the amount of the nitrogen oxide emissions. In addition, according to the arrangement of the low $NO_x$ burners the methods of applying their $NO_x$ reduction efficiency were proposed. The $NO_x$ reduction efficiency for the facilities consisting of the low $NO_x$ burners and the non-low $NO_x$ burners could be estimated with information about the reduction efficiency of each low $NO_x$ burners, the fuel consumption rate, and the heating value of fuel.

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The Fundamentals of Reduction of UO22+ Ions on a Pt Electrode and Methods for Improving Reduction Current Efficiency

  • Yeon, Jei-Won;Pyun, Su-Il
    • 전기화학회지
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    • 제10권2호
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    • pp.73-81
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    • 2007
  • This review article considered the electrochemical reduction of uranyl ions on a Pt surface. Specifically, we focussed on the improvement in its reduction current efficiency. First, this article briefly explained the fundamentals of the reduction of uranyl ($UO_2^{2+}$) ions on a Pt surface. Namely, they involved the electrochemical behaviour of uranium species, and electrochemical cell configurations for the reduction of $UO_2^{2+}$ ions. In addition, the effects of adsorbed hydrogen atoms were investigated on the reduction of $UO_2^{2+}$ ions. Finally, this article presented the methods for improving current efficiency of the reduction of $UO_2^{2+}$ ions on a Pt surface. Three different kinds of methods are introduced, which include electrochemical surface treatments of Pt electrode involving hydrogenation and anodisation, the use of catalyst poisons, and formation of thin mercury film on a Pt electrode. Moreover, this article provided some clues about how hydrogenation and catalyst poisons work on the reduction of $UO_2^{2+}$ ions.

기존 건축물의 에너지 효율화 리트로핏 패키지 방안 (Energy efficiency retrofit package plan for existing buildings)

  • 김수민;조현미
    • 토지주택연구
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    • 제11권1호
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    • pp.95-101
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    • 2020
  • In the past few decades, the global population growth and rapid economic development have resulted in significant increases in building energy consumption. To reduce greenhouse-gas emissions and building energy consumption, building materials and energy technologies must be optimized. Building retrofitting is a more efficient method than reconstruction to improve the building energy performance. In order to improve the energy performance of existing buildings, this study proposed energy-efficiency retrofit plans and derived cost-effective retrofit plan. The energy efficient retrofit method is achieved through the packaging of energy technology and the energy and cost reduction effect of the energy efficiency retrofit package are analyzed. As a result of the study, the energy-efficiency retrofit package showed an energy reduction effect of up to 60% or more and a construction cost reduction of about 30%. This study argues that optimal energy and construction cost reduction of existing buildings are possible through the packaging of energy efficiency technology.

감수제의 감수 효율에 따른 다성분계 결합재를 사용한 콘크리트의 물리적 특성에 관한 기초적 연구 (A Study on the Physical Characteristics of Concrete using Multi-Component Blended Binder According to Warter Reduction Efficiency of Warter Reduction Agent)

  • 김경환;오성록;최병걸;최연왕
    • 콘크리트학회논문집
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    • 제27권5호
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    • pp.559-568
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    • 2015
  • 본 연구에서는 감수제의 감수 효율에 따른 다성분계 결합재를 사용한 콘크리트의 물리적 특성에 대한 영향을 평가하기 위하여 고성능 감수제의 종류 3수준(0%, 8% 및 16%) 및 물-결합재비 3수준(40%, 45% 및 50%)에 따른 플라이애시 및 고로슬래그 미분말을 사용한 다성분계 콘크리트 배합을 제조하였다. 또한, 신뢰성 확보를 위하여 콘크리트 배합은 3회 반복실험을 실시하였다. 실험결과, 감수제 종류에 따른 압축강도는 약 20% 이상의 압축강도 차이가 발생하였으며, 감수제의 감수 효율이 콘크리트의 품질에 크게 영향을 미치는 것으로 나타났다. 따라서 감수제의 감수 효율을 반영한 다성분계 콘크리트의 압축강도 예측 모델식을 도출하였으며, 90% 이상의 높은 상관성이 있는 것으로 나타났다.

경계층 외부 수직날의 마찰저항 저감 기구에 대한 PIV 관측 (PIV Investigation on the Skin Friction Reduction Mechanism of Outer-layer Vertical Blades)

  • 박현;안남현;박성현;전호환;이인원
    • 한국가시화정보학회지
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    • 제9권1호
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    • pp.20-28
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    • 2011
  • An experimental assessment has been made of the drag reducing efficiency of the outer-layer vertical blades, which were first devised by Hutchins. The drag reduction efficiency of the blades was reported to reach as much as 30%. However, the drag reduction efficiency was quantified only in terms of the reduction in the local skin-friction coefficient. In the present study, a series of drag force measurements in towing tank has been performed toward the assessments of the total drag reduction efficiency of the outer-layer vertical blades. A maximum 9.6% of reduction of total drag was achieved. The scale of blade geometry is found to be weakly correlated with outer variable of boundary layer. In addition, detailed flow field measurements have been performed using 2-D time resolved PIV with a view to enabling the identification of drag reduction mechanism.

Analysis on an Oxidation-Reduction Reaction of Photocatalytic Plasma Complex Module

  • KIM, Young-Do;KWON, Woo-Taeg
    • 웰빙융합연구
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    • 제5권2호
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    • pp.21-27
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    • 2022
  • Purpose: This study is about photocatalytic technology and plasma oxidation-reduction technology. To the main cause of exposure to odor pollution, two deodorization techniques were applied to develop a module with higher removal efficiency and ozone reduction effect. Research design, data and methodology: A composite module was constructed by arranging two types of dry deodorization equipment (catalyst, adsorbent) in one module. This method was designed to increase the responsiveness to the components of complex odors and the environment. standard, unity, two types of oxidizing photo-catalyst technology and plasma dry deodorization device installed in one module to increase the potential by reduction to 76% of ozone, 100%, and 82%. Results: The complex odor disposal efficiency was 92%. Ammonia was processed with 50% hydrogen sulfide and 100% hydrogen sulfide, and ozone was 0.01ppm, achieving a target value of 0.07ppm or less. The combined odor showed a disposal efficiency of 93%, ammonia was 82% and hydrogen sulfide was 100% processed, and ozone achieved a target value of 0.07 ppm or less. Conclusions: Ozone removal efficiency was 76% by increasing Oxidation-Reduction Reaction(ORR). The H2S removal efficiency of the deodorizer was higher than that of the biofilter system currently used in sewage disposal plants.

수치계산에 의한 축류터보기계의 유동장과 유동온실의 평가 III [회전차 익말단의 누설손실과 효율저하에 대한 평가] (Evaluation of Flowfield and Flow Losses insied Axial Turbomachinery Using Numerical Calculation [Evaluation of Tip Leakage Loss and Reduction of Efficiency by Tip Clearance])

  • 노수혁;조강래
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 1998년도 유체기계 연구개발 발표회 논문집
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    • pp.240-247
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    • 1998
  • Leakage vortices formed near blade tip causes an increase of total pressure loss near casing endwall region and as a result, the efficiency of rotor decreases. The reduction of rotor efficiency is related to the size of tip clearance. In this study, the three-dimensional flowfields in an axial flow rotor were calculated with varying tip clearance under various flow rates, and the numerical results were compared with experimental ones. The effects of tip clearance and attack angle on the leakage vortex and overall performance, and the less distributions were investigated through numerical calculations. In this study, tip leakage flow rate and total pressure loss by tip clearance were evaluated using numerical results and aprroximate equations were presented to evaluate the reduction of rotor efficiency by tip leakage flow.

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수치계산에 의한 축류터보기계의 회전차 익말단의 누설손실과 효율저하에 대한 평가 (Evaluation of Tip Leakage Loss and Reduction of Efficiency of Axial Turbomachinery Using Numerical Calculation)

  • 노수혁;조강래
    • 한국유체기계학회 논문집
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    • 제2권1호
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    • pp.73-80
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    • 1999
  • Leakage vortices formed new blade tip causes an increase of total pressure loss near the casing endwall region and as a result, the efficiency of rotor decreases. The reduction of rotor efficiency is related to the size of the tip clearance. In this study, the three-dimensional flowfields in an axial flow rotor were calculated by varying the tip clearance under various flow rates, and the numerical results were compared with experimental ones. The effects of tip clearance and attack angle on the leakage vortex and overall performance, and the loss distributions were investigated through numerical calculations. In this study, tip leakage flow rate and total pressure loss by tip clearance were evaluated using numerical results and approximate equations were presented to evaluate the reduction of rotor efficiency by tip leakage flow.

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