Simulation Study On Municipal Solid Waste Pyrolysis Characteristics And Life Cycle Assessment Methodology

Recently our country's economy has been continuing rapid growth,and people's living standard improving,but the output of municipal solid waste is also a sharp rise,which casues serious environmental and social problems so that seriously affects the natural environment and people's normal life.The traditional ways,such as sanitary landfill,composting and incineration,have all sorts of shorts.So it is immediate cation of disposal of garbage which should be reduction,recycling and innocent.It is a technical direction in line with national policies and economic development trends to use pyrolysis for waste treatment.Therefore,this paper will conduct simulation research and life cycle assessment on waste pyrolysis,and explore the influencing factors and environmental impacts of low-temperature pyrolysis process of waste.Based on the chemical process simulation software Aspen Plus,this paper selects the typical components of plastics and rubber in municipal solid waste,establishes a low-temperature pyrolysis reaction model,then adjusts the pyrolysis temperature,sets different pyrolysis atmospheres and mixes different component proportions to simulate further and analyze the effects on the distribution of pyrolysis products and their yield,especially the effects of semi-coke yield,carbon emissions,and pollutant emissions.Then the life cycle assessment model is established by using eBalance software,and the process of model can be divided into four links of garbage collection product transportation,drying,pyrolysis,separation,which should be counted of input and output?i.e.,resource consumption and pollutant emission?,then make a list of that to quantitative analysis,and make the influence assessment by selecting six environment impact index of GWP?PED?CADP?AP?EP and RI.According to the quantitative analysis data,the links which should be improved first can be pointed out,which provides the basis for the optimization of the system.The results show that the reaction results are the best at 400°C.At this temperature,the mixing of N₂ and non-combustible gas has the best pyrolysis process,and the mixture of plastic and rubber is also optimally mixed.Under this simulated condition,the calorific value of semi-coke,the solid product obtained by pyrolysis,is 24.96MJ/kg,higher than that of general lignite,and it can be directly used as industrial raw material and fuel.In eBalance,The global warming potential is the most important environmental impact caused by the system,which is the type of impact that should be optimized first.The CH₄ in the exhaust emission can be recycled to reduce the GWP value.The environmental impact value of the pyrolysis link in the system link accounts for a large proportion,and it is necessary to focus on the optimization of the link,which can be solved by optimizing the selection,energy saving treatment and efficiency improvement of the pyrolysis equipment.