Sand Manufacturer Modernizes Silo Aeration with Resulting Cost Savings

From more productive oil extraction to more durable coatings to scratch-resistant screens for our smart phones, high-quality sand plays a big part in our daily lives. U.S. Silica is a leading sand manufacturer and supplier of state-of-the-art products that are now matched by equally modern aeration devices for its storage silos.

“Five years ago, we embarked on a project to convert our screen style air pads to a better method of aeration. The pads were breaking off and contaminating the material requiring shutdowns,” explains Tom Proctor, production manager at the company’s Ottawa, IL mine. “I discovered the Solimar aeration system and began a replacement program. I haven’t regretted that decision.”

The sand product at this site is a finely ground crystalline silica supplied to the oil and gas market for hydraulic fracturing. The primary application is an additive to cement that slows the hydration of the slurry in high-temperature environments (hydration retardation) and enhances long-term performance of the cement sheath or wellbore plug. Also, enhanced long-term performance of the cement is achieved when finely ground crystalline silica is admixed with certain other cement additives. In selected hydraulic fracturing applications, fine ground silica can also be used as a fluid-loss control additive in hydraulic fracturing fluids to improve the volumetric efficiency. The product is produced from naturally mined sand that is ground to specification in a rotary ball mill.

The Solimar aerator utilizes silicone disks positioned strategically inside the silo, bin, or hopper. Compressed air provides the energy to move the material while the edges of the disk flutter to provide gentle vibration to loosen the product. The resulting action prevents bridging, rat holing, and compacting. The disks are available in various materials to be compatible with food-grade products or high-temperature applications.

In order to maintain the failing air pads in eight of its 120-tn silos, U.S. Silica had to shutdown rail- and truck-loading operations and workers were required to enter the vessels. “Since we have installed the Solimar disk-type aerators, we haven’t had to send anyone into a silo for aeration maintenance,” said Proctor. The company prefers to avoid enclosed workplace issues whenever possible. Using technical assistance from Solimar, the company decided on eight aerators per silo. These were easily installed without entering the confined space using the Solimar EZ-IN system.

The retrofit EZ-IN uses a unique gasket material to compensate for any imperfections in the silo. Since the gasket is permanently affixed to the mounting plate, installation was expedited. The zinc-plated, carbon steel mounting plate is compatible with flat or conical hoppers. Stainless steel plates are also available for food-grade applications. Three mounting plate styles are available to retrofit most existing hole patterns.

“We haven’t had to replace any of the disks in five years so maintenance has been nothing compared to air pads,” explains Proctor. “That is a savings of $8500 in maintenance alone.” Proctor also praised the low-profile aerators for their excellent flow characteristics and wear resistance with “very abrasive” sand. Proctor adds, "Keeping our employees safe and seeing a cost savings is a great achievement."

For more information on Solimar products, visit www.solimarpneumatics.com.