Case Study: TASKMASTER® TM8512 Twin Shaft Grinder Goes the Distance

The city of Longview, Texas Waste Water Treatment Plant treats the wastewater generated by approximately 100,000 customers. The plant handles an average of 15MGD with a maximum of 21 MGD and has the ability to handle 60MGD for short periods of time. The facility is a trickling filter/ activated sludge plant with tertiary filters and ultraviolet disinfection. Sludge is treated in four anaerobic digesters and subsequently dewatered. The effluent is discharged into the Sabine River and eventually flows into the Toledo Bend Reservoir.

For the past 25 years, the plant has undergone various upgrades and expansions including the installation of a TASKMASTER® 8512 Twin Shaft Grinder. According to Scott Baggett, Utility Plant Manager, the unit, installed in 1999, has been extremely dependable and reliable. “The macerator continuously processes waste activated sludge from four final clarifiers,” he explained. “The sludge is pumped approximately 1200 feet to the macerator and then to the Primary Thickener.”

The TASKMASTER TM8500 Inline is a high performance, twin shaft grinder that provides powerful size reduction capabilities, easy maintenance and exceptional durability. The unit features CUTTER CARTRIDGE® technology which increases unit strength completely and eliminates the need for cutter stack re-tightening.

With the TASKMASTER TM8500, banks of individual cutters and spacers are replaced by the one piece CUTTER CARTRIDGE. By eliminating these multiple parts, maintenance is dramatically simplified. These cutting elements are machined from solid alloy steel or stainless steel using a proprietary manufacturing process. The result is a high strength grinder that has a remarkable resistance to cutter and spacer cracking.

The cutters are installed on two counter rotating shafts, intermeshing one with another at close clearance to shear and shred solids into fine bits. One shaft feeds solids to the center of the unit while the other shreds them. The output achieved is easily processed by downstream equipment such as pumps, centrifuges, and belt filter presses.

The TASKMASTER can be successfully installed in sewage treatment plants, sludge lines, and pumping stations. It is supplied for open channel or in-line applications

Mr. Baggett recently expressed his satisfaction with the TM8500 “The unit was rebuilt in October, 2005. Since the rebuild, the macerator has been running like a champ!”