In designing a wastewater solution to significantly reduce heavy metals in battery manufacturing effluent, we incorporated technologies that had never previously been combined to achieve a totally closed-loop solution. Our process was awarded a patent and remains the best available technology for this industry.
New regulatory permits required substantial reductions in effluent heavy metals and total dissolved solids concentrations at the largest lead-acid battery manufacturing complex in the US. With rudimentary lime neutralization and clarification, it was challenging to comply with the proposed regulatory changes.
Our approach
We designed and managed the construction of a closed-loop process wastewater treatment and process water reclamation facility to recover distilled water and a commercial anhydrous sodium sulfate byproduct from the sulfuric acid-based process wastewater.
The process separates all lead-containing residues from the treated water and recycles them in the on-site secondary lead smelter. The recovered water is reused in manufacturing for acid cutting and all other water-consumer processes. In addition to membrane separation, the system includes a falling film evaporator and forced-circulation crystallizer.
Outcome
Constructing this facility enabled East Penn Manufacturing Company to close loop all process wastewater, resulting in total regulatory compliance and recycling 100 percent of water and process byproducts. The facility has successfully operated since 1996, producing more than 2,900,000 gallons of recycle/make-up water per week.
When East Penn Manufacturing embarked on a doubling of production capacity in 2009, they called AECOM to increase the capacity of the zero-liquid discharge system. In response, we doubled the capacity of the thermal water recovery and sodium sulfate generation processes.