Life-cycle Integrated Contrastive Analyses Of Liquefied Natural Gas(ING)heavy-duty Vehicle And Its Diesel Counterpart

Under the dual pressure of oil energy consumption and environmental pollution,clean energy powered vehicles have developed rapidly in recent years.Some heavyduty vehicle(HDV)companies have developed LNG HDVs to replace diesel HDVs in the context of environmental policies and rising fuel prices.But how to compare the energy-saving and emission-reduction effects of the two types of HDVs? Only by quantitatively evaluating life-cycle ecological effects(including ore material consumption,energy consumption and environmental emissions).Thus,this article applied the methods of life cycle assessment to construct a theoretical model of static and dynamic evaluation of the life cycle differences of the two types of HDVs,and takes two certain LNG and diesel HDVs as examples for practical comparative analyses to draw reliable conclusions.The main research contents are:(1)Put forward the general idea of the comparative study on the life-cycle of LNG and diesel HDV.Firstly,analyzes the problems existing in HDV industry of China and the necessity of developing LNG HDVs;then,points out the problems in the current life-cycle assessment methods of LNG HDVs;finally,the idea of life-cycle integrated contrastive analyses of LNG HDV and its diesel counterpart is put forward.(2)The static evaluation models for the ecological effect differences of two types of HDVs were constructed.Firstly,analyzes the evaluation objectives and system boundaries and determines the functional units and evaluation objects;then establishes the accessory mass difference matrix of two types of HDVs.Based on this matrix,establishes the life-cycle inventory difference analysis model of two types of HDVs,and analyses the Chinese local production inventory data;finally,establishes life-cycle impact assessment models of two types of HDVs.(3)The dynamic evaluation models for the ecological effect differences of two types of HDVs were constructed.Firstly,based on the theory of system dynamics,the dynamic evaluation system and the causal relationship between internal elements is analyzed,and then the dynamic evaluation models for the ecological effect difference of two types of HDVs were established,and the system variables that have a greater impact on the ecological effect differences between the two types of HDVs are selected for dynamic simulation.(4)Carry out a case analysis of the ecological effect differences of two types of HDVs.Static evaluation results show that LNG HDV perform worse than diesel heavy trucks in terms of resource depletion(ADP),photochemical smog(POCP),and greenhouse effect(GWP),but perform better in terms of acidification effects(AP)and human toxicity(HTP).When increasing the use ratio of material preparation with the same times,steel can reduce more ADP value than aluminum;when two types of HDVs reduce the same times of gas(oil)consumption in 100 kilometers,LNG HDV can reduce more life-cycle energy consumption and ADP,GWP values than diesel HDV.But in terms of AP,HTP and POCP,it performed poorly.Combining the evaluation results and the investigation of LNG HDVs manufacturers,suggestions for the development of LNG HDVs in China are summarized.