Ziang Zhao

Recycling used battery packs for electric vehicles has important economic and ecological benefits. However, existing studies lack a systematic comparison of the different models. There is also a lack of exploration of symmetrical bilateral disassembly lines in comparison to other disassembly lines. Therefore, this paper takes the battery pack dismantling line of a company as the object of study. The disassembly line model is established by considering the number of workstations, disassembly time, disassembly costs, and disassembly risks. This study quantifies the risk of disassembly at each process into specific indicators for modeling. The solving algorithm adopts the improved Northern Goshawk Optimization Algorithm and the Non-dominated Sorting Genetic Algorithm. A simulation demonstration was conducted using plant simulation to compare the advantages and disadvantages of the unilateral disassembly and symmetric bilateral disassembly line programs. The results show that the optimized unilateral and symmetric bilateral disassembly line schemes increase the efficiency by 23.08% and 38.46%, respectively, compared to the original program. The symmetric bilateral disassembly line scheme is the most efficient among the programs. The optimized schemes significantly improve the overall operational efficiency of the disassembly line. Programs to promote increased efficiency in battery recycling will contribute to environmental sustainability.

Straw burning can cause serious environmental pollution, whereas returning straw to the fields, as a green production method, can improve the rural environment and strengthen the sustainable development of agriculture. According to statistics, China produced 797 million tons of straw in 2020, but the current straw return technology still needs to be improved; the ability of farmers to choose the correct amount of straw to be returned to the field and their awareness of environmental protection still need to be strengthened. Straw is still openly burned in some areas, causing environmental pollution and the waste of resources, which are contrary to the concept of sustainable development in China. In this study, we estimated the amount of straw resources in Heilongjiang Province, a major grain-producing province in China, by quantifying the production of major crops between 2011 and 2020. We then identified and analyzed the current problems in terms of policy support and other aspects. We used an integrated AHP-fuzzy evaluation method to evaluate the comprehensive benefits of different straw return amounts, and we determined the amount of straw that should be returned to the soil to produce the best comprehensive benefits. We provide suggestions for the current main problems regarding the amount of crop straw to return to the soil in Heilongjiang Province, arguing that choosing a reasonable straw return amount will help farmers increase profit, reduce environmental pollution, and contribute to the sustainable development of the environment.