This PFI: AIR Technology Translation project focuses on translating an electrochemical water treatment process that will increase water recovery and decrease waste brine production during nanofiltration (NF) and reverse osmosis (RO) water purification. The electrochemical pretreatment process will enable large-scale inland desalination using RO and NF. Currently, large-scale RO and NF are not commonly practiced in non-coastal areas due to the high costs of brine disposal. Decreasing the volume of brine production by one order of magnitude will make inland RO and NF cost-effective. This will enable both municipally treated wastewater and brackish groundwater to be used as sources of potable or industrial water. These two new sources of water will obviate water scarcity imposed restrictions on economic development in arid regions of the country. The project will result in a proof-of-concept for operating a fluidized bed crystallization reactor using base solutions produced via bipolar membrane electrodialysis. In contrast to commercialized pretreatment processes for RO and NF that only remove particulate contaminants, the proposed process removes both dissolved contaminants and particulates larger than 5 µm. This will greatly reduce membrane fouling and increase water recovery compared to conventional pretreatment processes for RO and NF.
Several key aspects of the proposed technology require proof-of-concept testing before commercialization. These include determining: 1) how system operating parameters affect removal of membrane fouling constituents; 2) the long-term operation and maintenance costs associated with operating the bipolar membrane electrodialysis reactor; and 3) the impact of micron-sized mineral solids on the concentrate side of a specially designed NF module. The testing will be performed using municipally treated wastewater at the Water and Energy Sustainable Technologies (WEST) Center that is co-located with the Pima County Agua Nuevo wastewater treatment plant. The experiments and testing will be performed by gradate and undergraduate researchers who will also participate commercialization workshops sponsored by Tech Launch Arizona and Innovate UA.
The project engages research partners EconoPure Water Systems, LLC, and HDR Engineering. EconoPure is an original equipment manufacturer producing unique NF modules that can be operated with particulates as large as 10 µm. EconoPure will be providing equipment and system design expertise, as well as commercialization assistance. HDR is a consulting firm that provides engineering and design services to industrial and municipal clients for both water and wastewater treatment. HDR will provide an objective, independent evaluation of this treatment technology based on their understanding of real world applications. As the technology's development warrants, HDR will help identify potential customers, and will also be involved in obtaining technology demonstration projects through collaborations with the Water Research Foundation (WRF), the Water Reuse Research Foundation (WRRF), and the Water Environment Research Foundation (WERF).