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www.rockproducts.com ROCK products • March 2017 • 55 Yerington contacted Clearwater Industries to investigate a potential solution. Founded in 1996 by Bob Gralton of Mequon, Wis., the Clearwater specializes in the design of polymer preparation systems, water clarifiers and fines recovery systems. Strategic and Tactical Solutions "Our strategy involves analyzing the application, evaluating the existing system and methods, and recommending the tactics and technologies that will deliver the desired results," said Joe Lamb, application engineer for Clearwater Industries. He added that it's been a joint effort with Wendling Quarries, working closely together on analysis, experimentation, lab testing, field testing and ongoing design improvements. For the Wendling site, the new custom-engineered sludge thickening clarification system has dramatically increased the percentage of solids in the discharge. With their prior setup, the percentage of solids averaged in the lower 20s. The new system ensures a consistent average of 64 to 68 percent solids, with solids as high as 77 percent depending upon the material feed. To keep the system simple and user-friendly, Yerington wanted to stick with a single 13,000-gal. clarification tank. The dirty process water is pumped into the clarifier as floc- culant is added via an automated system. Very clean water overflows the top of the clarifier and can go right back to the plant for reuse. The underflow, or thickened mud is discharged and is ultimately transferred to a final resting place. "Now we can convey the discharge material 100-ft. to an initial containment area where it dries in less than a week. Eventually we will pump the material rather than using a conveyor," said Yerington. Clearwater's automated flocculant system, said Lamb, is dosing the polymer automatically based upon the varying solids level. "That is such a critical issue as the right chem- istry must exist to allow the clarification process to work," he said. Also, Lamb stressed that the operation had been using a two-part-chemistry treatment that included a very expen- sive cationic component. "After our lab tests, we could Material is automatically dosed with flocculants again when it enters the discharge pipe, before being conveyed to a containment area.