Implementation of circular economy of water in the automobile batteries recycling industry

Circular economy arises as an alternative to facilitate sustainable development in the industrial sector by enhancing water resource efficiency, reducing wastewater generation, and establishing closed-loop systems. This study presents two approaches to implement circular economy of water in the automobile batteries recycling industry. In these proposals, the key principles driving the circular economy model (reduce, reclaim, reuse, recycle, recover, and rethink) were considered, emphasizing the essential role of reduction, direct reuse, reclaiming, recycling, recovery and rethinking in achieving sustainable water management. Survey and measuring campaign were done to determine flowrates and characteristics of freshwater, wastewater, and treated wastewater stream. Then, water and pollutants mass balances were conducted. As a result, i) important reductions on freshwater consumption (69.5%) and total water inputs (> 66.0%) in the industrial process can be achieved by implementing direct wastewater reuse; ii) direct wastewater reuse and wastewater recycle can be increased in 12% and 18%, respectively, thus contributing in reducing 6.2% the wastewater generation; iii) batteries´ electrolyte is the main source of wastewater pollutants; therefore, it is recommended to rethink and redesign the industrial process to extract batteries’ electrolyte before they are processed; implementing this strategy will contribute in recovering 0.31 m 3 /1,000 batteries/month (248 m 3 /month) of concentrated sulfuric acid, achieving zero disposal of wastewater, attenuating aquifer pollution by heavy metals and salts, and reducing wastewater treatment costs in 90%, which represents savings greater than US$ 90,000.00/month or 1.15 million US dollars per year. • Transition to a circular economy of water in the industry is achievable and feasible • Circular economy can help the industry sector to face water shortages worldwide • Important water reductions can be achieved: freshwater (69.5%), total water inputs (66.0%) • These strategies potentialize direct wastewater reuse (12.0%) and recycling (18.0%) • Zero wastewater disposal and recovery of valuable constituents can be achieved • Important savings can be obtained in wastewater treatment (>US$ 1.15 million/year)