Emergy based sustainability evaluation of spent lead acid batteries recycling

Sustainability evaluation of lead acid batteries recycling enables quantitative analyses of the true value of resources, the environment and economy of the processes thus to provides recommendations to improve process sustainability. However, the environmental impacts of pollutants haven't been considered in the emergy-based sustainability assessment indicators. To this end, an improved emergy analysis method is proposed to evaluate the efficiency and sustainability of the lead acid batteries recovery process system. Firstly, the ecological effects of pollutant emissions are converted to equivalent waste emergy using dilution, eco-indicator 99 and the land erosion methods. Then, the waste emergy and product emergy are included in the emergy index system to provide improved emergy indices. In addition, in order to assess the system's resource recovery rate and clean production level, technical efficiency and environmental have been included into the performance indicators. Finally, according to the evaluation results of emergy indicators, improvement measures for the optimisation system can be improved. To verify the feasibility of the proposed method, the sustainability evaluation of the production process of the lead acid batteries recycling system (including disassembly, classification and various separation materials processing processes) is conducted, and the results show that pollutant emissions reduce the effectiveness and sustainability of the system. This method reflects the overall performance of the system, compared with the traditional emergy method. The proposed method can be utilized as an effective tool for sustainability evaluation and optimisation of lead acid batteries recovery process system.