Life Cycle Assessment Of Compressor Rotors Based On Multiple Inventory Analysis Methods

With the increasingly severe environmental and resources problems,various techniques have been widely concerned at home and abroad,such as ecological design,green manufacturing and cleaner production,and so on.Life Cycle Assessment(LCA)which is an effective and objective method to evaluate the environmental impact of product,process or activity has been studied intensively and applied widely.The compressor is a kind of important industrial equipment which is widely used in various industries.A comprehensive evaluation and analysis of the resources,energy consumption and environmental emissions in the whole life cycle of a large centrifugal compressor,and gives some reasonable improvement measures,which has important practical significance.This paper first elaborates the research background,reviews the research status of life cycle assessment methods,software tools and life cycle assessment of mechanical products at home and abroad,introduces research meaning and research contents.Then,the main LCA methods are analyzed,including process-based LCA,input-output-based LCA and hybrid LCA.And the problem of data double-counted in hybrid LCA is improved.Next,the life cycle inventory analysis and life cycle impact assessment are conducted for the compressor rotor based on process life cycle assessment method in detail,including raw materials production,raw materials transportation,rotor manufacture,rotor transportation,use and disposal.The evaluation results show that the comprehensive environmental impact of the compressor rotor usage stage occupies 75% of the whole life cycle stage.The comprehensive environmental impact of impeller production accounts for 89.4% of the total production stage.The comprehensive environmental impact of milling process accounts for 86.7% of impeller production.The life cycle inventory analysis and life cycle impact assessment are conducted for the compressor rotor based on input-output analysis and three hybrid analysis models,the differences and causes of the environmental impacts of different models are compared and analyzed.Some guidelines are proposed for the using and selection of LCA methods.The integrated hybrid model takes full account of the two-way relationship between the process system and the upper and lower sectors of the national economy.The data collection requirements are the highest,and the results among the three hybrid analysis methods are the highest.Compared with P-LCA,TH-LCA and IOH-LCA methods,the results of IH-LCA increase by 57%,16% and 24%,respectively.This paper evaluates the data quality based on the uncertainty analysis and sensitivity analysis concluding that results from process data are more accurate and more reliable.The use time and price of the compressor rotor are very sensitive to the LCA results.According to the results of life cycle inventory analysis and environmental impact assessment,the environmental improvement analysis of the rotor production,transportation,usage and end-of-life disposal stages are conducted respectively.In the production stage,the main measure is reducing the consumption of raw materials and energy.The focus of the transport phase is to reduce the automobile exhaust emissions.In the usage stage,the main measures are improving the efficiency of the compressor and optimizing the power structure.The environmental performances of three waste treatment schemes(whole landfill,recycling and remanufacturing)are compared and analyzed.Compared with the whole landfill,remanufacturing decreased by 33%,31%,31%,31% and 44% in PED,GWP,AP,EP and POCP respectively.This paper also designs and develops a prototype software system with process life cycle assessment and input-output life cycle assessment,and import some Chinese product data inventory and environmental impact factors.At the end of this paper,the main research achievements are summarized,the deficiencies of the research are analyzed and the future research is prospected.