Research On Environmental Evaluation Model Based On Life Cycle Thinking And Its Application In Aluminium Industry

Life cycle assessment(LCA) and materials flow analysis (MFA) are two important environmental evaluational tools based on life cycle thinking. LCA plays an important role in the assessment of clean production and green products. MFA is also becoming an important tool in analyzing consumption of materials and energy in national level as an important technical support to circular economy. The aim of the research is to establish the model for LCA and MFA and to use for China aluminium industry with a view of sustainable development of China's aluminum industry, The main results are as follows:1?A MEP (Material-energy-Process) inventory analysis model is proposed in LCA research and a cumulative life-cycle assessment model is established which operation simple and fast.2?A process-oriented input-output LCA model is established To solve the LCA border problem, the process environmental burden of the aluminum industry is calculated which is the first systematic research on environmental performance of aluminium related products and processes. The results indicates:1) The combination of Bayer process for alumina production with aluminium smelting(inert anode) and Hydropower is the best practice for the aluminium industry environmental performance. On the other hand, The combination of sinter process for alumina production with aluminium smelting(Hall-Heroult process) and fire power is with the worst environmental performance2)8249kg of sce is consumed in aluminum industry per tons of aluminum which is 4.69 times of the direct energy consumption in the process;also, its carbon dioxide emissions is 23.55t per ton of aluminum, which is 14 times of its direct emissions.3) CO2 and the largest source of power consumption is the result of bring the indirect environmental load to the process by the fire power. Change the current power structure, from thermal coal-based power to Hydropower is an important way to reduce the environmental burden and to abtain sustainable development of aluminum industry 4) Comparing Bayer method, sinter method and Bayer-sinter combination method for the alumina production, the sintering process is with the worst environmental performance. On the other hand, the Bayer method is with the best environmental performance. the steam producton process which cause indirect environmental burden gives the largest contribution to the life cycle. To reduce the consumption of steam or increase steam energy conversion efficiency is an important way to improve the environmental performance of alumina industry.3?In the improvement analysis stage, the concept of eco-efficiency is introduced and a DEA-based LCA model is established. Different processes for aluminum industry is compared and its potential for improvement is pointed out4?A MFA model based on entropy analysis is established and the gray logistics model results show that:the relative overall entropy of aluminum products are 0.027 and 0.022 in 2005 and 2007, respectively. The aggregation of aluminum-containing material degree increased.