Study The Influence Of Biodiesel From Waste Cooking Oil On Heavy Duty Diesel Engine Emissions

Facing the urgent need of energy conservation and emission reduction,the development of alternative fuels for internal combustion engines is of great significance for reducing the dependence of imported crude oil and reducing environmental pollution in China.When the diesel engine burns biodiesel,it not only produces NO_x,CO,CO₂,THC,PM and other conventional pollutants,but also produces alkanes,alkenes,aromatic hydrocarbons,aldehydes and ketones containing oxygen compounds.These unconventional discharge pollutants are harmful to human health and the environment.In this paper,a series of studies were carried out on the emission effects of biodiesel on the heavy-duty vehicle and the high-power diesel engine of engineering marine.Based on the C-WTVC cycle,the experimental study on the vehicle of heavy-duty vehicle was carried out,and the variation of conventional emission,particulate component and gaseous unconventional emission of heavy-duty vehicle with biodiesel mixing ratio and vehicle operating condition was discussed.The diesel engine of two pumps in an engineering marine was tested,and the change of pollutant emission from B10 biodiesel to D100 was analyzed.In this paper,the emission test systems for heavy-duty vehicles and engineering marine were built.The conventional emission pollutants such as NO_x,CO,CO₂,THC,and particle count were measured online.At the same time,the differences between different cars are analyzed and particulate filter membrane samples and gaseous emission samples were collected.The results show that with the increase of biodiesel mixing ratio,NO_x emission per mile of heavy-duty vehicles gradually increases,and the emission of CO,THC and PM decreases,and the increase of nuclear particulate makes PN increase.NO_x emission sharing rate is mainly concentrated in urban operating conditions and high-speed operating conditions,while CO and THC sharing rate is mainly concentrated in urban operating conditions,and fuel consumption and CO₂ emissions are correspondingly increased.The carbon component analysis of OC and EC,water-soluble ion analysis and inorganic element analysis were carried out on the particulate matter respectively.The results show that OC and EC account for 48.14%±17.82%and 38.27%±17.29%of the PM respectively.After burning biodiesel,water-soluble ions account for 31.31%±12.08%of the total PM.The total amount of inorganic element components accounts for 9.20%±4.97%of the total mass of PM.In the analysis of particulate carbon composition of diesel engines used in pumps of engineering marine,it is found that OC1 and OC2 accounted for the major part,and they account for more than 62.06%of the total organic carbon,and EC2 has the highest content in EC1,EC2 and EC3.By summa canister and gas chromatography-mass spectrometry（GC-MS）,the effects of biodiesel on the concentrations of non-conventional substances such as aldehydes,ketones,aromatic hydrocarbons,alkanes and alkenes were analyzed.The results show that with the increase of biodiesel blending ratio,the total mass concentration of VOC_S first decreases and then increases.The mass concentrations of alkanes,halogenated hydrocarbons and alkenes in B10biodiesel increased relative to D100,but the mass concentrations of heavy-duty vehicle emissions decreased with the increase of mixing ratio,while the mass concentrations of aromatic hydrocarbons and aldehydes and ketones increased.For heavy-duty vehicles,benzene,toluene and m-p-xylene are the main aromatic hydrocarbons,accounting for an average of 54.14%.Ethanol,acetone,ethyl acetate,n-butyl acetate,benzaldehyde and acetaldehyde account for 80.31%of oxygen-containing compounds.For engineering marine diesel engine,the highest proportion of aldehydes and ketones reach 93.30%.