Environmental Impact Assessment Of Automobile Manufacturing Process And Exhaust Emission Based On LCA

Since China’s accession to the WTO in 2001,China’s automobile industry had developed rapidly,ranking first in terms of annual and sales volume for ten consecutive years.As of 2018,the car ownership reached 230 million,second only to the United States.With the development of automobile industry,a lot of environmental pollution was produced in the process of automobile manufacturing and putting into use.In addition,the air pollution caused by automobile exhaust emission was becoming more and more serious,which had become the main source of urban air pollution.The environmental problems of automobile industry have become the focus of environmental protection in China.Data analysis and impact assessment were carried out on the impact of automobile production and using,especially for exhaust emissions on the environment,in order to provide theoretical foundation and technical guidance for the sustainable development of China’s automobile industry.The main contents and results were as follows:Aiming at the environmental impact analysis of automobile manufacturing process,this paper took the four manufacturing processes stamping,welding,coating and general assembly as the research object.Firstly,the pollution emission and prevention situation in the process of automobile manufacturing were investigated,and the main pollution sources and pollutants were determined by the equal standard pollution load method.The pollution source and pollutant with the largest load proportion were the centralized exhaust pipe(46%)and Volatile Organic Compounds(VOC_s)(85.1%).The process improvement measures to reduce VOC_s emission were put forward,and the emission was expected to be reduced by75.2%.Then,the environmental impact caused by the four major automobile manufacturing processes was comprehensively evaluated,including resource consumption and energy consumption.The evaluation method was Life Cycle Assessment,and the evaluation process was completed with eBalance software.The degree of environmental impact was characterized by digital results.This paper mainly selects five kinds of impact indicators of China’s resource consumption(CADP),water resource consumption(WU),eutrophication(EP),acidification(AP)and inhalable inorganic substances(RI).The evaluation results showed that automobile manufacturing process had the largest impact on China’s resource consumption(81%),which was much higher than the environmental impact(6%)caused by pollutant emissions.The contribution of different manufacturing processes to the impact index was analyzed.The evaluation results showed that the coating process had the greatest contribution to various environmental impacts,and was the process that causes the greatest comprehensive environmental impact,which the contribution ratio was 65.6%.Strengthening resource management and improving energy utilization rate can reduce the comprehensive impact on the environment,which is conducive to the sustainable development of automobile industry.The environmental impact analysis of vehicle exhaust emissions:1.From the perspective of pollutant emissions,combined with vehicle ownership in three aspects of vehicle type,fuel and exhaust emission standards,the data utilization value was mined,including the growth trend of different types of vehicle ownership and pollutant emissions.Based on the data analysis in 2018,the Logistic Growth Model was used to predict the growth of vehicle ownership in 2025 to 407.836 million vehicles,and the corresponding growth of pollutants will to be CO(63%),HC(61%),NO_x(53%)and PM(55%).According to the results of data analysis,suggestions were put forward to deal with the growth of pollutants in the future,which can completely reduce the increment of NO_x and PM in 2025.2.From the perspective of environmental impact,this paper used e Balance software to evaluate the environmental impact caused by automobile exhaust emissions in 2018,and selects three types of impact indicators:EP,AP and RI.The results showed that the contribution of vehicle exhaust emissions to EP was the largest,accounting for 18%of the total impact potential value of China’s EP,followed by AP(10%)and RI(4%).The contribution of different types of vehicles to the impact types was analyzed.The contribution of heavy-duty trucks accounting for 3%of the number of vehicles was about 5times that of minibuses which account for 87%of the number of vehicles.Among all models,the exhaust emissions of heavy-duty trucks had the greatest impact on the environment,and their NO_x emissions contribute more than 50%to all kinds of impacts.Therefore,increasing the emission control of heavy trucks in various types of vehicles in China,focusing on reducing the NO_x emissions,can reduce the environmental impact caused by vehicle exhaust emissions as a whole,which is conducive to the sustainable development of the automobile industry.