In 2009, the Wastewater Treatment Plant of West Lafayette, Indiana seized revenue and energy-savings opportunities for the thousands of gallons of grease the facility receives per month. The treatment plant implemented a major upgrade and installed two microturbines to generate electricity to make use of the methane produced in their digesters. The plant also installed a grease receiving station to convey grease to the digesters to increase methane production for the microturbines.
The plant handles, on average, 18,000 gallons of grease per month, and the material varies widely in consistency and fluidity. Thick grease prevents heavy solids from settling in the metal trap, while thin grease allows most of the debris to flow through the grease tank uninhibited. The plant soon found that, without a grinder on the discharge side of the grease trap, debris from the thicker grease entering the grease tank would get pulled into the grease pump and cause blockage, severe damage and continual maintenance at a big expense to repair the pump.
To solve the problem, the plant installed a JWC Environmental Heavy Object Trap (HOT) in 2011. The HOT (model GRS) features an adjustable bar screen with ½ inch (12mm) spacings, ideal for catching debris before reaching the pump. As grease is unloaded from the truck, the debris is captured by the HOT bar screen and allows the grease to flow freely through the pump without process interruption.
Since the installation of the HOT, the plant has significantly reduced the amount of debris being discharged into the grease tank. Plus, the easy-to-clean bar screen has cut down on operator maintenance and repair expense, decreasing downtime for the facility.