top of page


Plant-wide Closed Loop Wastewater Recycling System

Precision Anodizing & Plating, a leading anodizing facility in Southern California, faced substantial operational costs and elevated sewer fees due to high water consumption. To address this challenge, Exergy implemented an efficient plant-wide closed-loop wastewater recycling system, incorporating our state-of-the-art Advanced Reverse Osmosis (ARO) technology and Electrodialysis (ED). The result was a remarkable 90 percent reduction in overall water consumption, accompanied by substantial cost savings and a significant decrease in sewer fees, establishing a sustainable and cost-effective solution for Precision Anodizing & Plating.



  • Reduced water consumption from 120,000 GPD to 10,000 GPD

  • Plant-wide closed-loop system with a payback of 2 years

  • Yearly savings in water costs, labor, and chemicals totaling $160,000

  • Recovery of rinse waters from plating operations

Exergy Design & Engineering's collaboration with Precision Anodizing & Plating (PAP) began with a previous project involving the design, testing, and installation of an acid recycling system on their anodizing line. During this venture, it became evident that the plant's escalating water consumption was driving up operational costs and sewer fees, prompting a need for a comprehensive water conservation solution. Drawing upon our extensive experience working with metal finishing companies spanning two decades and closely cooperating with PAP's management, we meticulously assessed the water flows to the five plating/anodizing lines. This in-depth analysis laid the foundation for developing a water recycling system tailored to the specific chemical characteristics of the wastewater.


The rinses were categorized into two wastewater streams, with one exhibiting low Total Dissolved Solids (TDS). This low TDS stream was directed to an Advanced Reverse Osmosis (ARO) system. The second wastewater stream, containing elements like aluminum, silica, and zinc, was channeled into an Electro-coagulation system before proceeding to a second ARO treatment. To further refine the process and prevent salt build-up from the rejected streams of the ARO systems, an electrodialysis (ED) system was incorporated. The permeates produced by the ARO and ED systems were efficiently recycled as rinse water, reinforcing sustainability efforts.


The amalgamation of these innovative treatment systems resulted in an impressive 90 percent reduction in water consumption, significantly curbing operational costs and sewer fees, thus alleviating the plant's monthly expenditures. Moreover, the successful implementation of the new water recycling system positioned PAP to qualify for the City Water Conservation Rebate program, further emphasizing the system's efficiency and contribution to environmental sustainability. This sophisticated water recycling technology has now been in operation for over two years.


Exergy's ARO technology emerged as a standout performer in this endeavor. It operates at elevated pressure, yielding higher concentrations in concentrates and superior-quality permeates. Notably, ARO's unique features, including recycle pump operation and patented membrane treatment, enable efficient operation across a wide pH range from 0.5 to 13. Beyond its exceptional performance, Exergy's ARO technology contributes significantly to reducing operating costs by enhancing the recovery and reuse of valuable waste by-products. Furthermore, our flexible ARO options and custom systems cater to diverse requirements, ensuring adaptability to evolving production needs and specific plant operating conditions. 

bottom of page