• 제목/요약/키워드: Volumetric Ratio

검색결과 386건 처리시간 0.024초

호기성 침지여상에 의한 제지폐수처리 (Papermill Wastewater Treatment by Indirect Aerated Submerged Biofilter)

  • 원찬희;권영호
    • 상하수도학회지
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    • 제8권1호
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    • pp.44-52
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    • 1994
  • The purpose of this experimental research was focused to improve the quality of the effluent and the yielded sludge when the papermill wastewater was treated by the indirect aerated submerged biofilter as a second treatment method of papermill wastewater. Changing the various experimental factors(Nutrient additions or not, HRT, F/M ratio, recirculation ratio, etc) with indirect aerated biofilter, the results obtained are as follows. 1. Because of the microbes concentration could be sustained to $9,000mg/l$ in submerged biofilter and then the volumetric organic loads could be increased to $2.7kg-BOD/m^3/day$(that of activated sludge is $0.8kg-BOD/m^3/day$), the reactor volume can be reduced to one third of the activated sludge treatment. 2. Because of the yield coefficient(Y) and the endogenous decay coefficient(kd) were revealed 0.4 and 0.07/d, the yielded sludge volume was reduced by for compared with that of the activated sludgg process. 3. The concentration of the sloughed sludge in the reactor was 2.62~4.01%, so the thickener could be omitted in the papermill wastewater sludge treatment process. 4. When the operating was conducted at HRT of 4hrs, the treatment efficiencies of BOD and COD were obtained 80% and 70%, Therefore operating time can be reduced to one half of the activated sludge treatment.

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PAC-A/O 공정을 이용한 안료폐수의 질소 제거 특성 (Nitrogen removal characteristics of pigment wastewater using PAC-A/O process)

  • 정종식
    • 상하수도학회지
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    • 제32권1호
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    • pp.19-25
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    • 2018
  • The objectives of this study were to evaluate the removal characteristics of total nitrogen, the influence factor of denitrification and the optimum operating condition in the pigment wastewater treatment using PAC-A/O process. The operating conditions of PAC-A/O process were mean BOD volumetric loading $0.86kgBOD/m^3/day$, mean F/M ratio 0.072~0.13 kgBOD/kgMLVSS/day and mean C/N ratio 3.47, respectively. The conditions of anoxic process in the field plant test were mean pH 8.3~8.7 and mean temperature $34.1{\sim}44.0^{\circ}C$. The ORP bending point knee was eventually appeared in the ORP -107 mV and $NO_3{^-}-N$ removal efficiency was increased according to the ORP decrease. In the ORP -107 mV below condition, the removal efficiency of T-N and $NO_3{^-}-N$ was 92.3~95.0% and 98.5~99.7%. Denitrification rate was calculated to be 1.581~1.791 mg $NO_3{^-}-N/gMLSS/hr$. The experimental results showed that the ORP control in the PAC-A/O process could be an effective method for treatment of pigment wastewater.

산촉매에 의한 대두유의 전이에스테르화 반응 특성 (Characteristics of Transesterification Reaction of Soy Bean Oil by Acid Catalysts)

  • 신용섭
    • 한국환경과학회지
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    • 제18권2호
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    • pp.231-238
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    • 2009
  • Characteristics of the transesterification reaction between triglycerides in soy bean oil and methanol were investigated in the presence of acid catalysts. such as sulfuric acid and PTS (p-toluene sulfonic acid). Concentrations of diglyceride and monoglyceride which were intermediates in the reaction mixtures, were far below 10% of triglyceride under any reaction conditions. Thus, conversion of the reaction could be determined from the concentration of triglyceride. Dried PTS had more superior catalytic power than sulfuric acid for transesterification reaction between soy bean oil and methanol. When transesterification reaction of soy bean oil was catalyzed by 1 wt% of PTS at methanol stoichiometric mole ratio of 2 and $65^{\circ}C$, final conversion reached 95% within 48 hours. If FAME (fatty acid methyl ester) was added into reaction mixture of soy bean oil, methanol and PTS catalyst, it converted reaction mixture into homogeneous phase, and substantially increased reaction rate. When reaction mixture was freely boiling which had equal volumetric amount of FAME to soy bean oil, methanol stoichiometric mole ratio of 2 and 1 wt% of PTS, final conversion achieved value of 94% and temperature approached to $110^{\circ}C$ within 2 hours.

개조된 LPG엔진에서 Mixer와 LPi 연료공급방식의 엔진성능 및 배기특성 (Engine Performance and Emissions Characteristics in an LPG Engine Converted with Mixer and LPi System Fuel Supply Methods)

  • 최경호;김진호;조웅래;한성빈
    • 대한기계학회논문집B
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    • 제28권9호
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    • pp.1075-1080
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    • 2004
  • In this study, performance and emissions characteristics of an liquefied petroleum gas (LPG) engine converted from a diesel engine were examined by using mixer system and liquid propane injection (LPi) system fuel supply methods. A compression ratio for the base diesel engine, 21, was modified into 8, 8.5, 9 and 9.5. The cylinder head and the piston crown were modified to roe the LPG in the engine. Ignition timing was controlled to be at minimum spark advance for best torque (MBT) each case. Engine performance and emissions characteristics are analyzed by investigating engine power, brake mean effective pressure (BMEP), brake specific fuel consumption (BSFC), volumetric efficiency, CO, THC and NOx. Experimental results showed that the LPi system generates higher power and lower emissions than the conventional mixer fuel supply method.

층상연료분사(경유/메탄올)를 이용한 디젤엔진의 NOx와 Soot 동시 저감에 관한 연구 (제1보 : 층상분사장치의 설계 및 층상분사 연소특성) (A Study on the Simultaneous Reduction of NOx and Soot with Diesel-Methanol Stratified Injection System in a Diesel Engine (Part I : Design of Stratified Injection System and Combustion Characteristics of Stratified Injection))

  • 강병무;김종률;이선봉;이태원;하종률
    • 한국분무공학회지
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    • 제5권2호
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    • pp.28-34
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    • 2000
  • To reduce the soot and NOx simultaneously, a new system of stratified injection is developed. This system discharges stratified diesel-methanol in a D. I. Diesel Engine. Nozzle and delivery valve of conventional injection system were remodeled to inject diesel and methanol from one injector sequently. The quantity of diesel and methanol was controled precisely by micrometers mounted on the injection control lack. The real injection ratio of dual fuel was measured by volumetric ratio. We could confirm the capabilities that soot and NOx simultaneously were reduced by diesel-methanol stratified injection from the results of in-cylinder pressure data obtained from combustion experiment by stratified injection, heat release rate and mass fraction bumed.

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상변화 물질을 사용한 축열조에서의 열전달 - 수직원관에서의 내향용융 실험 - (Heat Transfer in Heat Storage System with P.C.M. - Inward Melting in a Vertical Tube)

  • 손화승;황태인;이채문;최국광;임장순
    • 태양에너지
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    • 제9권1호
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    • pp.53-61
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    • 1989
  • In the present investigation, experiments on the melting of a phase change material were performed to research heat transfer phenomena generated by means of conduction and natural convection in the vertical tube at inward melting. The phase change material used in the experiments is 99 percent pure n-Docosane paraffin which is measured melting temperature of $42.5^{\circ}C$, latent heat of 37.5 cal/g, heat conductivity of $0.1505W/m^{\circ}C$. Experiments were performed both in the no-subcooling which is initiating it at melting temperature of phase change material, and in the subcooling which means to initiate it under melting temperature of phase change material, in order to compare and investigate the horizontal temperature history, vertical temperature history, ratio of melting and melted mass, figure of the melting front in the vertical tube. In the experimental results, heat transfer from tube wall to phase change material were due to conduction at early stage and due to natural convection with the passage of time, and then occurred melting downward from surface by volumetric expansion. Natural convection affects temperature distribution in the tube, ratio of melting and melted mass, figure of the melting front and then progress rapidly in case of nosubcooling compared to subcooling.

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마이크로 X-ray CT를 활용한 알루미늄 개방형 폼의 형상 및 압축 거동 분석 (Analysis of 3D Geometry and Compressive Behavior of Aluminum Open Cell Foam Using X-ray Micro CT)

  • 김영일;김지훈;이종국;김대용
    • 소성∙가공
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    • 제20권7호
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    • pp.518-523
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    • 2011
  • The three dimensional geometries of an aluminum open cell foam before and after uniaxial compressive loading were investigated using the X-ray micro CT(computed tomography). Aluminum 6101-T6 open cell foams of 10, 20, 40 ppi (pore per inch) were considered in this work. After the serial sectioning CT images of aluminum foams were obtained from non-destructive X-ray images, the exact 3D structure were reproduced and visualized with commercial image processing program. The relative density ratio was around the 7.0 to 9.0 range, the unit cells showed anisotropic shapes having the different dimensional ratios of 1.1 to 1.3 between the rise and the transverse directions. The yield stress increased with the relative density ratio and the volumetric strain increased proportionally with compressive strain. The plateau stress in the compressive stress-strain curve was caused by the buckling of ligaments.

층상연료분사(경유/메탄올)를 이용한 디젤엔진의 NOx와 Soot 동시 저감에 관한 연구 (제2보 : 층상분사 연소특성 및 배기 특성) (A Study on the Simultaneous Reduction of NOx and Soot with Diesel-Methanol Stratified Injection System in a Diesel Engine (Part II : Combustion and Exhaust Characteristics of Stratified Injection))

  • 강병무;이태원;정성식;하종률
    • 한국분무공학회지
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    • 제7권1호
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    • pp.7-13
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    • 2002
  • This paper is study on simultaneous reduction of NOx and soot for direct injection diesel engine using high and low cetane fuels. The stratified injection system was applied for diesel engine to use high and low cetane fuel. In this study, diesel fuel was used as high cetane fuels, methanol was used as low cetane fuels. Some parts of the injection system, ie. Nozzle holder. delivery vale, was remodeled to inject dual fuel sequentially from one injector. The leak injection quantity ratio of dual fuel was certificated by volumetric ratio at injection quantity experiment. According as concentration of low cetane fuel was varied, combustion experiment was performed using Toroidal and Complex chamber. Also, exhaust gas and fuel consumption were measured at the same time. Simultaneous reduction of NOx and soot was achieved at complex chamber regardless of concentration of low cetane fuel. However, according as concentration of low cetane fuel was increased, THC and CO was increased.

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Phenol 함유폐수의 처리를 위한 영향인자와 성능특성 (Influence factors and Efficiencies Characteristics for Treatment of Wastewater Containing Phenol)

  • 강선태;김정목
    • 상하수도학회지
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    • 제10권4호
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    • pp.119-126
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    • 1996
  • Influence factors and efficiency characteristics for treatment of wastewater containing phenol were studied with using Pseudomonas sp. B3. It took 130 hours to remove phenol, when only activated sludge of terminal disposal palnt of sewage was innoculated in batch culture, but it was required just 36 hours, when bacteria degrading phenol and activated sludge were simultaneously innoculated. If only phenol an carbon source was used, it necessary 36 hours for biodegradation of phenol, while glucose was added to medium, it took 73 hours. It was revealed as excellent effluent and SVI, when the F/M ratio, COD and phenol concentration were 53mg/l and 1.2mg/l, respectively, and optimum F/M ratio was revealed 0.31. The reactor were seriously shocked as reducing hydraulic retention time at constant phenol concentration more than increasing phenol concentration at constant hydraulic retention time, when volumetric loading rate was increased to $0.8kg\;phenol/m^3{\codt}d$ from $1.6kg\;phenol/m^3{\codt}d$. And also the effluent phenol concentration was 34mg/l after starting 12 hours of shocking and reactor was recovered as steady state after 65 hours of changing in the former test. Although the effluent phenol concentration was maximum value with 12mg/l after starting 20 hours of shocking and reactor was recovered as steady state after 54 hours of changing in the later test.

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축분을 이용한 바이오가스 엔진 개발 - 기초설계 및 성능분석 - (A Study on the Development of Bio-gas Engine Using Livestock Manure - Fundamental Design and Experimental Analysis on the Performance -)

  • 백이;김영중;강금춘;유영선;조기현
    • Journal of Biosystems Engineering
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    • 제30권6호통권113호
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    • pp.354-359
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    • 2005
  • This is a fundamental study to develop a bio-gas utilization technology using livestock manure. Especially, this study was carried out to develop an engine using bio-gas. A bio-gas engine was designed and manufactured by modification of a diesel engine of 3 cylinders powering 13.31 kW/2800 rpm, changing the fuel supplying system fit for bio-gas. The result showed that, when the Air/Fuel ratio was controlled with fixed spark timing, the power of biogas-fueled engine is about $10.6{\~}14.6\%$ lower then that of LNG-fueled engine because of low volumetric efficiency. The engine output and torque was $11.85{\~}13.3$ kW, $39.5{\~}40.8\;N{\cdot}m$, respectively at the engine speed of 2600 rpm. Bio-gas consumption rate was 260.20 g/kW/hr, 315.20 g/kW/hr in engine speed or 1000 rpm, 2800 rpm, respectively.