Today, water sustainability is a priority for most cities and states. For utilities, this means investing in filtration systems that are not only cost-efficient, but also produce high water recovery and low amounts of waste. These systems can help to conserve water and limit the discharge of hazardous wastewater into waterways, which are typically heavily regulated by local authorities. If you are looking for a more sustainable water treatment solution, one of the following technologies may work well for your utility’s needs:
- Backwash/Recycle Systems
Backwash/recycle systems help to conserve water by storing and treating contaminated backwash water from filtration and treatment systems, so that it can be recycled within or outside of the utility. The systems are a great addition to existing treatment solutions and can be used with most adsorption, oxidation/filtration or coagulation/filtration systems. When implemented, the backwash/recycle systems are able to conserve up to 99.7 percent of water.
- Biological Filtration
Biological filtration is an option for water utilities that treat water with high ammonia levels. The process uses naturally occurring bacteria present in groundwater to enhance the natural nitrification process that converts ammonia to nitrite and then nitrate. Not only does biological filtration treat ammonia and other contaminants like arsenic, iron and manganese to non-detectable levels, it also results in high recovery rates. And because the process doesn’t use chemicals, the low-volume waste that is produced is non-hazardous.
- Flow Reversal Reverse Osmosis (FR-RO)
Reverse osmosis (RO) is a common filtration technology, but some systems require a lot of water to operate. Flow reversal reverse osmosis (FR-RO) desalination technology offers facilities a solution for brackish water and other industrial applications. The systems save water by periodically switching the flow direction of the saline stream so that scale does not have time to form on membrane surfaces before under-saturated feed solution conditions sweep it away. Using under-saturated feed to sweep away scale particles in the concentrate before they exceed a critical size prevents extensive precipitation and allows for higher recovery. FR-RO systems produce near zero limit discharge and boast up to 20 percent increase in water production, 20 percent decrease in raw water consumption and 60 percent decrease in brine volume.