Safe Silo Cleaning The Whip Keeps Material Flowing
When the Eagle Materials Illinois Cement facility experienced a serious blockage in its 80 000 ton storage silo, the company employed an innovative pneumatic cleaning technology that was remote controlled from outside the domed structure.
One of the United State’s leading manufacturers of cement and other building materials has overcome a severe blockage of Type I cement in its 80 000 short ton (approx. 72 000 tonnes) capacity storage silo by employing an innovative pneumatic cleaning technology that was remote controlled from outside the domed structure. The Eagle Materials Illinois Cement facility experienced the blockage when a support cable on the reclaim screw conveyor came loose, sending thousands of pounds of material down into the silo at one time. But with the unique whip design of the cleaning equipment and some round-the-clock dedication from a Martin Engineering crew, the accumulation was efficiently cleared and loaded out, allowing repair personnel to set up a crane and lift the auger back into position.
The unique design of the equipment allowed it to be lowered from the top through a manhole opening, and although the crew was on-site around the clock for nearly a month, the material could be loaded out with normal operating procedures. “During the process, we were able to use our auto load-out system from the bottom of the dome, because the material being knocked down fell primarily in the centre,” recalled Chief Chemist and Quality Control Manager Kevin Jensen. “There was no need to transfer cement in the tunnel, and that helped minimise the disruption.”
Founded in 1964, Eagle Materials is one of the nation’s largest cement providers, with four plants supplying a combined total of about 4 million short tons (approx. 3.6 million tonnes) annually. The company’s Illinois Cement facility in LaSalle manufactures approx. 1.1 million short tons (approx. 1 million tonnes) of that total each year.
A Massive Task
Like most cement manufacturers, the plant uses large storage vessels to hold finished material until it’s ready for shipment. At the LaSalle facility, the domed storage unit is 99 ft (approx. 30 m) tall and 186 ft (approx. 56 m) in diameter.
During the course of normal operations, the cable connectors on the reclaim screw worked themselves loose, causing the auger to fall onto the pile and halting the flow of material. The only way to rectify the situation was to position a crane over the top and lift the conveyor out, so the cable could be reattached. But to do that, operators first needed to clear out enough material to access the disabled equipment, a massive task in light of the nearly-full dome.
“Our first step was coming up with a plan to tackle the load-out job,” recalled Chief Chemist and Quality Control Manager Kevin Jensen. “We needed to remove a significant amount of material in order to make the repair, and there was just no easy way to go about it.”
Jensen contacted Martin Engineering, Neponset (IL), USA, for assistance, and technicians were on site to inspect the situation the next day. They reviewed the options and determined that the best approach was to employ the Martin Heavy Duty Whip, one of several technologies making up the company’s Silo Solutions product line.