Concrete Products covers the issues that attract producers of ready mixed and manufactured concrete focusing on equipment and material technology, market development and management topics.
Issue link: http://concrete.epubxp.com/i/551927
40 • August 2015 www.concreteproducts.com A family-owned business established in 1993 with 5-yd., single-axle truck, Ready Made Concrete Inc. has grown to a fleet of 26 full-load mixers, serving decorative concrete interests in Salt Lake City and, more recently, commercial slab and wall contractors. "Single- or two-truck deliveries were our maximum load size— it was a good fit for municipalities, small cities, little communities where there was a real need and demand for smaller loads," says Ready Made owner Paul Philips. "We filled the need there and just grew." CHALLENGES Located in an urban area, Ready Made has limited space on site to dispose of material. For years, plant staff used settling pits, which took up a large area and required near-daily muck removal. "The slurry was just that— liquid, messy and sloppy," notes Philips. "It was impossible to contain and as a result we were tracking slurry through our yard, and the trucks were tracking it into the streets and into public right of way." Once the settling pits had been mucked out, Ready Made was paying to have material hauled and disposed of. The vessels tended to leave waste material heavy and laden with water, boosting trans- portation costs. "We're within Salt Lake City, so we're not in an area where we can get rid of waste just by pushing it on the back 40," Philips affirms. "We're on a small, paved lot, and part of the agree- ment with West Valley City was to control and maintain process water on site." SOLUTION On 2014 World of Concrete day one, Philips and his sons noticed a new, innovative piece of equipment: the Concrete Washout System filter press, centerpiece of the McLanahan Corp. booth. After gaining insight on filter press operation and conditions where customers had deployed such a unit, the Ready Made team's interest was piqued. "We were having an issue with water and contamination, and trying to reuse settle water," Philips notes, adding that the Concrete Washout System has "a small footprint and we thought it would fit within the area designed for our reclaiming system." Through several meetings, he and his sons provided McLanahan sales and engineering staff data on the Salt Lake City plant site and fleet, helping determine the appropriate Concrete Washout System, which features a 15-plate filter press with 630-mm x 630-mm plates that produce a 35-mm thick cake and is designed to handle up to 400 tons of cement fines per day. After sufficient brainstorming with fam- ily and McLanahan staff, recalls Philips, "I could really see this being an important piece to our ready mixed puzzle." A Concrete Washout System with overall footprint of around 15- x 20-ft. was installed adjacent to Ready Made's existing reclaimer. Oper- ators early on observed a significant amount of sand was escaping the reclaimer and being passed along to the filter press, which is best suited to dewatering cement fines into easily handled, dry cakes, and recovering clear water with low suspended solids. Joined by McLanah- an representatives, says Philips, "We investigated, 'Why are we having problems with the press or the filters?,' and ultimately discovered that we were losing 50 percent of the sand." Based on extensive experience with fine sand processing, McLa- nahan engineers suggested their Separator, a cyclone fitted with an underflow regulator to improve recovery at the reclaimer and limit fil- ter press-bound material to primarily cement fines and water. "McLa- nahan engineered the whole process for us. We installed the cyclone and the pumps as designed, and all of a sudden we were recovering 100 percent of our sand," says Philips. RESULTS Recovery of sand has been extremely important: Ready Made can reuse it in most ready mixed orders, while eliminating hauling costs. Admitting limited knowledge of the Separator prior to the order, Philips recalls, "We evaluated and realized we were losing 50 percent of our sand. The Separator was a quick payback once we realized that we could recover material we were just hauling to the landfill." Return on the Concrete Washout System investment is easily calculated by the recovered sand alone, he adds. Additional savings and ROI are reflected in reduction of trips to the landfill—to which low-moisture cement fine cakes are dispatched. Indeed, filter press INNOVATIONS REPORT ENVIRONMENTS Filter press elevates best process-water management practice at Ready Made Concrete The flter press confgured to ft into Ready Made's existing truck washout station. It utilized the existing former settling pits as stor- age for recycled water, suited to truck washing and washout. Paul Philips Continued on page 42