Combustion gas and NO emission characteristics of hazardous waste mixture particles in a fixed bed

Ling Tao,Guangbo Zhao,Rui Sun 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.3

Experiments with fixed-bed incinerators were carried out to model the combustion characteristics and gas emission characteristics of hazardous waste mixture particles in a grate furnace. The results indicate that combustion can be divided into three stages: ignition, main combustion and combustion completion stage. According to the various concentrations of O_2, CO-2 and CO, the main combustion stage can be subdivided into pyrolysis gas combustion and char combustion. Primary air rate, moisture and particle size have significant effects on concentrations of combustion gases and NO. Bed height has no effect on CO-2 concentrations but does have an effect on other combustion gases and NO emissions.

Experimental Investigations on Spray Characteristics of Potential Fuels for Advance Low Temperature Combustion Engines

( Saurabh Kumar Gupta ),( M. Murugesa Pandian ),( Anand Krishnasamy ) 한국액체미립화학회 2017 한국액체미립화학회 학술강연회 논문집 Vol.2017 No.-

Advanced low temperature combustion (LTC) strategies including Premixed Charge Compression Ignition (PCCI), Reactivity Controlled Compression Ignition (RCCI), Stratified Charge Compression Ignition (SCCI) and High Efficiency Clean Combustion (HECC) are proposed to simultaneously reduce oxides of nitrogen (NOx) and particulate matter (PM) emissions to near zero levels along with higher thermal efficiencies. However, precise control of ignition timings is difficult to achieve in these LTC strategies as it is primarily controlled by the molecular composition of fuel by altering physical and chemical delay period and creating reactivity stratification. Fuel spray characteristics plays a vital role in varying the rate of fuel-air mixing and physical delay period. The potential fuels for advanced LTC modes include fuels with optimal reactivity and better volatility. The effects of physical properties and its impact on spray behavior of potential fuels for LTC are sparsely available. The present work intends to study the effects of changes in properties and injection pressures on the macroscopic spray behavior of potential fuels for advanced LTC engines. The experiments are carried out in a constant volume spray chamber with different potential fuels for advanced combustion engines, viz. Diesel with 10%,20% and 30% gasoline (DG10, DG20 and DG30) and Diesel with 10%,20% and 30% kerosene (DK10, DK20 and DK30). The fuel injection pressures and the injection strategies have been chosen as representative of direct injection diesel engine working conditions. The spray characteristics such as spray tip penetration distance, spray cone angle are obtained by using a high resolution spray visualization system for the different fuel blends. The obtained results show that the changes in physical properties of the fuel blends affect the macroscopic fuel spray behavior. Further, as compared to that of conventional diesel, all the fuel blends show a significant difference in the macroscopic spray characteristics.

직접분사식 커먼레일 DME엔진의 성능 및 배출물 특성

안상규(Sang Gyu An),김명윤(Myung Yoon Kim),윤승현(Seung Hyun Yoon),이제형(Je Hyung Lee),이창식(Chang Sik Lee) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper is to investigate the effect of injection parameter and exhaust gas recirculation on the combustion characteristics and emission characteristics of a common rail direct injection diesel engine. In order to investigate the effect of combustion characteristics and emission reduction of DME fuel, the experiment was performed at various injection pressure from 35 ㎫ to 50㎫. Also, the exhaust emissions from the engine were compared with that of diesel fuel. In this work, 30% , 45% of EGR was implemented to reduce NOx. exhaust emissions. The results showed that DME has shorter ignition delay than that of diesel fuel. Despite of the increased NOx, emissions with DME at an equal engine power compared to the case of fueling diesel, the engine emitted zero soot emissions all over the operating conditions in this work. NOx. emission can be decreased greatly by adopting 45% of EGR while maintaining zero soot emission. Judging from the engine test, DME is suitable fuel for common-rail diesel engine due to it's clean emission characteristics.

The effects of the air-fuel ratio on a stationary diesel engine under dual-fuel conditions and multi-objective optimization

Cho, Jungkeun,Park, Sangjun,Song, Soonho Elsevier 2019 ENERGY Vol.187 No.-

<P><B>Abstract</B></P> <P>The fundamental combustion characteristics and engine performance of a dual-fuel engine, fueled with diesel and natural gas, were investigated using a commercial 1D simulation program (GT-Power). Furthermore, the effects of air-fuel ratio under dual-fuel combustion conditions were studied, and optimized design points that minimize brake-specific fuel consumption (BSFC) and nitrogen oxides (NO<SUB>X</SUB>) emissions simultaneously were determined using a multi-objective Pareto optimization method. The engine model was validated based on experimental results and previous work under various engine loads. The thermal efficiency of the engine, which was modified from a diesel to a dual-fuel engine, showed a decreasing tendency as the natural gas substitution ratio (NSR) increased due to changes in the combustion characteristics. The decline in thermal efficiency in dual-fuel combustion could be improved somewhat by optimizing the injection strategy. Under dual-fuel combustion conditions, an optimum air-fuel ratio value for BSFC could be determined, especially for higher NSR conditions. However, NO<SUB>X</SUB> emissions showed a tendency to increase with increasing air-fuel ratio. The relationship between the trends was more than a simple tradeoff, so multi-objective Pareto optimization was conducted to minimize both BSFC and NO<SUB>X</SUB> emissions, with start of injection timing and air-fuel ratio as variables. Ultimately, optimal design points were determined.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The large stationary engine was modeled and modified to dual-fuel engine. </LI> <LI> The characteristics of dual-fuel combustion were investigated. </LI> <LI> The effect of air-fuel ratio under dual-fuel combustion condition are investigated. </LI> <LI> The optimal design points for improving fuel economy and NOx emission are suggested. </LI> <LI> Helpful methodology for conceptual design of virtual engine system was suggested. </LI> </UL> </P>

A Numerical Study on Combustion Characteristics in a Syngas-Diesel Dual Fuel Engine

( Abubaker Ahmed ),( Ali Kabbir ),( Changup Kim ),( Yonggyu Lee ),( Seungmook Oh ),( Kiseong Kim ) 한국액체미립화학회 2018 한국액체미립화학회 학술강연회 논문집 Vol.2018 No.-

The objective of this study is to analyze the combustion characteristics of an LSLB(Low calorific Syngas Lean Burn) dual-fuel engine, operated under overly lean conditions of syngas for power plant usages. A comprehensive chemical kinetics and computational fluid dynamics analysis were performed. In the present work, syngas is derived from coal that consists of H₂, CO and a high percentage of N₂ and CO₂, having low calorific value. This syngas is used with the similar amount of diesel to compensate for the excessive lean condition of syngas. The results indicate that most of diesel is burned as premixed combustion mode in dual fuel engine, then flame propagates through the syngas region in the piston bowl and squish zone. The hydrogen content affects little in the squish zone combustion. The effects of several injection parameters on the combustion characteristics were investigated also.

정적연소기에서 직접분사식 바이오 에탄올-가솔린 혼합연료의 연료온도에 따른 분무 및 연소 특성에 관한 실험적 연구

박기영 ( G Y Park ),김종민 ( J M Kim ),이성욱 ( S W Lee ) 한국액체미립화학회 2014 한국액체미립화학회 학술강연회 논문집 Vol.2014 No.-

As environment problem became a worldwide issue, countries are tightening regulations regarding greenhouse gas reduction and improvement of air pollution problems. With these circumstances, one of the renewable energies produced from biomass is getting attention. Bio-ethanol, which is applicable to SI engine, showed a positive effect on the PFI(Port Fuel Injection) type. However, Ethanol has a problem in homogeneous mixture formation because it has high latent heat of vaporization characteristic and in the GDI(Gasoline Direct Injection) type, mixture formation is required quickly after fuel injection. Particularly, South Korea is one of the countries with great temperature variation among seasons. With this reason, South Korea supply fuel additive for smooth engine operation during winter. Therefore, experimental study and investigation about application possibility of blending fuel is necessary. This paper demonstrates the spray and combustion characteristic by using the CVC direct injection and setting the bio-ethanol blending fuel temperature close to the temperature during each seasons: -7, 25, 35℃. The diameter and the width of the CVC are 86mm and 39mm. High-pressure fuel supply system was used for target injection pressure. High-speed camera was used for spray visualization and combustion visualization. Exhaust gas was measured by using the gas analyzer after combustion. Fig.1 represents the schematic diagram regarding the experimental apparatus. The experiment was conducted by setting the injection pressure and ambient pressure according to each temperature of bio-ethanol blending fuel as a parameter. The result of spray visualization experiment demonstrates that as the temperature of the fuel is lower, the atomization quality is lower, and this increase spray penetration and make mixture formation difficult. Injection strategy and combustion strategy according to fuel temperature and bio-ethanol blending rate is needed for improving characteristics.

직접분사식 바이오에탄올-가솔린 혼합연료의 분무 및 희박연소 특성에 관한 실험적 연구

박기영 ( Gi Young Park ),강석호 ( Seok Ho Kang ),김인구 ( In Gu Kim ),임철수 ( Cheol Soo Lim ),김재만 ( Jae Man Kim ),조용석 ( Yong Seok Cho ),이성욱 ( Seong Wock Lee ) 한국분무공학회 2014 한국액체미립화학회지 Vol.19 No.3

As a demand for an automobile increases, air pollution and a problem of the energy resources come to the fore in the world. Consequently, governments of every country established ordinances for green-house gas reduction and improvement of air pollution problem. Especially, as international oil price increases, engine using clean energy are being developed competitively with alternative transportation energy sources development policy as the center. Bio ethanol, one of the renewable energy produced from biomass, gained spotlight for transportation energy sources. Studies are in progress to improve fuel supply methods and combustion methods which are key features, one of the engine technologies. DI(Direct Injection), which can reduce fuel consumption rate by injecting fuel directly into the cylinder, is being studied for Green-house gas reduction and fuel economy enhancement at SI(Spark Ignition). GDI(Galoine Direct Injection) has an advantage to meet the regulations for fuel efficiency and CO2 emissions. However it produces increased number of ultrafine particles, that yet received attention in the existing port-injection system, and NOX. As fuel is injected into the cylinder with high-pressure, a proper injection strategy is required by characteristics of a fuel. Especially, when alcohol type fuel is considered. In this study, we tried to get a base data bio-ethanol mixture in GDI, and combustion for optimization. We set fuel mixture rate and fuel injection pressure as parameters and took a picture with a high speed camera after gasoline-ethanol mixture fuel was injected into a constant volume combustion chamber. We figured out spraying characteristic according to parameters. Also, we determine combustion characteristics by measuring emissions and analyzing combustion.

직접분사식 커먼레일 단기통 디젤엔진에서 EGR율에 따른 연소 및 배기특성

허정윤(Jeong Yun Heo),차준표(Junepyo Cha),윤승현(Seung Hyun Yoon),이창식(Chang Sik Lee) 한국자동차공학회 2011 한국 자동차공학회논문집 Vol.19 No.2

The purpose of this work is an experimental investigation of combustion and emission characteristics in DI diesel engine applied high EGR rate as a method of low-temperature combustion. In order to analyze the effect of EGR rate variation, a single-cylinder DI diesel engine was operated under various EGR rate conditions. In addition, injection timing was variously controlled to investigate the effect of injection timing in DI diesel engine using the cooled-EGR system. The NOx emissions were decreased in accordance with the increase of EGR rate. On the contrary, soot emissions were generally increased under applied EGR conditions. However, soot emissions were decreased in a few injection timings under high EGR rate conditions. The EGR results show that the ignition delay were increased by decreased oxygen concentrations in combustion chamber under the high EGR rate.

강제 맥동류를 이용한 연소특성 연구

양영준(Young-Joon Yang) 한국기계가공학회 2012 한국기계가공학회지 Vol.11 No.5

The combustion characteristics using forced pulsating flow were experimentally investigated with confined premixed flames stabilized by a reward-facing step. The intermittent combustion has many merits, for instance, such as high load combustion, high heat transfer, low emission gas, compared with those of continuous combustion. For these purposes, data processing of binary image was conducted to reveal the differences between intermittent and continuous combustion. As the results, it was possible to calculate the reaction zone using OH-emission band and, therefore, showed that forced pulsating flow was useful in combustion technology.

함산소 및 파라핀계 혼합 디젤유 액적의 연소특성에 관한 연구

김봉석(Bongseock Kim),宮本 登(Noboru Miyamoto) 한국자동차공학회 2006 한국 자동차공학회논문집 Vol.14 No.2

The single droplet combustion characteristics of multicomponent fuel such as diesel-oxygenate and diesel-paraffin blends under high ambient temperature and atmospheric pressure were investigated in the study. The results of the study may be concluded as follows : In the combustion of diesel fuel droplet with additive of oxygenate and paraffin, the dimensionless droplet size of (D/D<SUB>o</SUB>)² was linearly decreased with time. A fuel droplet with low boiling temperature additives and in high boiling temperature diesel fuel evaporates and burns faster than usual diesel fuel. This rapid burning may result from so-called “micro-explosion” and its burning intensity varies with the types of additives. The results above may suggest that rapid evaporation of oxygenate additive in the middle stage of combustion can contribute much to combustion improvement of blended fuels. When compared to ordinary diesel fuel, neat oxygenate and paraffin fuels show blue flame during entire combustion which prove smokeless combustion.