How Wastewater Can Become a Vital Resource for Industry in a Circular Economy
UN Water estimates that by 2025, 1.8 billion people are expected to be living in countries and regions with absolute water scarcity. In light of this impending crisis, water reuse is growing in importance, especially in drought-prone regions. Applying the water reuse mentality to business operations can help ease stress on groundwater sources and the supply of drinking water. Heineken recently opened a plant in Northern Mexico – a region with frequent severe droughts – that purifies water used in production and reuses 30% of it in other processes. This is a circular economy model that other sectors can follow to close the loop on industrial wastewater.
Wastewater can’t simply be reused without treatment. That treatment always involves the removal of organic carbon and can sometimes require recovering nutrients like nitrogen and phosphorous, which can also be reused as fertilizer for an added circular boost. Making wastewater reuse a success for industrial purposes can require nutrient treatment beyond regulatory requirements, depending on the particular operations. The challenge is achieving those elevated requirements without large capital investments that can prohibit adoption. For example, a major Californian wastewater plant sends some of its wastewater effluent to a nearby power plant for use as cooling water, which helps reduce the use of drinking water for this purpose. While this excellent example of water reuse can be replicated in other parts of the country, there could be a stumbling block to optimizing this new resource. Although the wastewater plant meets regulations for effluent ammonia levels, that legal amount of ammonia can lead to a phenomenon in pipes called ammonia-induced stress corrosion cracking when reusing the wastewater as cooling water in power plants.
Scaling up water reuse to its full potential will take additional planning, but thinking beyond traditional tactics can lower the barrier to entry. If that California wastewater treatment plant could reduce its ammonia levels below the regulatory requirements, the power plant would be able to use even more of the treated wastewater for cooling. Technologies that expand a wastewater treatment plant's processing capacity without large infrastructure investment can make closing the loop on industrial wastewater attainable by improving output. Some of those creative technologies are already helping now; advanced modeling tools combined with Drylet's proprietary microbe-delivery system can help a wastewater treatment plant increase its nutrient recovery capacity within its existing footprint. The technology relies on targeted microbes rather than increased chemicals or new equipment to process wastewater faster and more thoroughly.
These are just a few examples of how we can tap into a better wastewater resource; many more examples exist, and even more are yet to be discovered. The circular economy is about matching up waste flows with processes and applications that can put those waste flows to use, and technology is a huge part of creating those matches. Combining the technology that is driving wastewater treatment with the technology that is driving our industrial processes has vast potential to help close the loop on industrial wastewater and keep our precious drinking water for drinking.
[Editor’s Note: Dr. Malcolm Fabiyi will be speaking on a panel alongside Veolia SourceOne and Veolia North America. The panel will have an operations focus, discussing how a sustainability strategy can revolutionize a company’s approach to workplace safety and efficiency goals. Click here to learn more.]