Membrane - Based Solutions for Challenging Waters

The frontier of water treatment is being defined by hybrid approaches and thoughtful design integration. The use of increasingly sophisticated processes is driven by the need to treat dramatically impaired water supplies while maintaining low cost, high utilization, and high operational flexibility. Industrial wastewaters present an additional challenge, with increasing regulations and water scarcity driving the demand for novel approaches to treatment and reuse. Integrating membrane technologies into water treatment trains is one notable opportunity to realize substantial advantages in cost and performance compared to the use of more conventional processes. Reverse osmosis is ideally suited to desalinate low fouling streams to moderate levels of recovery. Recent innovations in reverse osmosis membranes and process design have enabled higher levels of recovery, extending the possibilities for application. Beyond reverse osmosis, the traditional answer for high salinity wastewater concentration is thermal evaporation. Dryers and crystallizers are typically used to convert saturated or organic rich liquors to solid products when zero liquid discharge is required; however, these unit operations are energy intensive and require high capital investment. Today, forward osmosis based brine concentration, enabled by high performance draw solutions and materials, is challenging this traditional paradigm. The integration of forward osmosis provides the opportunity to do more work with membrane-based processes and lessen the reliance on thermal systems, thereby reducing energy demand and capital costs. Equally important as the proper selection of technologies, is the integration of the unit operations and design of tailored pretreatments to enable robust, reliable solutions. In this discussion, we will cover membrane separations and explore how the integration of novel membrane technologies, in particular forward osmosis, provides new opportunities to deliver flexible and cost-effective solutions to treat difficult industrial wastewaters, minimize brine streams, and recover fresh reusable water.