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www.rockproducts.com ROCK products • July 2017 • 27 in sand specifications, we were forced to add washing capacities, so we wanted a lower cost, lower maintenance solution that would limit water use. We have our own well but it only pumps 220 gal.- per-minute," he said. The local Superior Industries dealer, Kimball Equipment, referred Rudolf to John Bennington. Soon thereafter, Rudolf and the local dealer flew to a quarry in Traverse City, Mich., to see the prototype of the Alli- ance Low Water Washer in action. According to Bennington, the Michigan operation is processing about 100 to 120 tph of feed through the low-water washer, and generally runs 200 to 250 gal.-per-minute of water, pumped from a well. The raw feed averages about 22 percent minus-200 mesh. At that rate, the conventional sand screw would require 1,100 gal.-per-minute. "After washing, the operation is achiev- ing under a 6 percent minus-200 mesh, with a target of 4 percent after further refinements," Bennington said. At the Michigan site, Rudolf ran pre- and post-wash samples through the new washer, and found that the unit would meet Rilite's specification requirements. This led to the installation of the Alliance Low Water Washer in February 2017. "I had the site ready to go, so it was a matter of unloading the truck, plus one day of hookup, and we were in busi- ness washing bedding sand at 175 to 200 tph – and it handles that capacity in such a small footprint, allowing us to install the washer without making any modifications to the existing plant," said Rudolf. He added that he's placed a belt stacker in front of the washer that can swing to feed the washer or swing away to bypass the washer when needed. Rudolf said that the low-water washer averages about 300 gal.-per-minute of water usage fed from a large fresh water pond that acts as a surge system for the well, which is used daily to fill the water trucks. "Versus the previous use of twin sand screws at 2,200 gal.-per-minute, I now vary my flow rate to the low-water washer between 200 to 400 gal.-per- minute. This has dramatically lowered our washing costs. We can conserve water, and manage its use without jeop- ardizing our need for water trucks for dust control," he stressed. Importantly, Rudolf points to the moisture content of the material after washing. "It's between 11 and 13 per- cent. With that, we can sell the product within one day. With our previous setup, we had 22-percent moisture content after washing and had to let the material sit and dry for about a week," he said, summing up the biggest advantage – "low water use and large throughput." The low-water washer averages about 300 gal.-per-minute of water usage.