The City of Houston, Texas, US, has awarded a contract to Veolia Water Technologies Inc. to supply what the company says is the world’s largest Hydrotech Discfilter system, to be used for tertiary treatment at the utility’s 69th Street Wastewater Treatment Plant (WWTP).

The 440 MGD peak daily flow tertiary Discfilter system is designed to handle influent with a peak total suspended solids of ≤100 mg/l, and produce an average monthly effluent of ≤10 mg/l. This upgrade to the current facility involves retrofitting the Discfilter system into the basins of the existing traveling bridge filters. The Hydrotech Discfilter system will include 19 units, each supplied with filter chassis as well as media and a backwash pump. Veolia will also provide spare parts, instrumentation and field services as part of the contract.

According to Veolia, the existing travelling bridge filters at the 69th Street plant are near the end of their life and need replacement. A team of the City’s employees and their local consultant evaluated proposals to replace the filters, reviewing both capital and long-term operations and maintenance costs. According to Veolia, the Discfilter offered the best value of those assessed and so was selected for the tertiary filtration treatment upgrade.

In a statement from Veolia, Shannon Dunne of the City of Houston comments: ‘The innovative Hydrotech design provides treatment within a small footprint and allows us to use the existing filter structure while increasing our filter capacity. The system’s design is user-friendly and allows operation and maintenance to be efficient and easy to perform. We will also be able to save in electrical and operation costs because of the efficiency of the process.’