Tervita Corp. controls dust

A Canadian environmental solutions firm operating a slag recycling plant in California is using industrial atomised mist technology to contain fugitive dust emissions and control runoff to satisfy strict state air quality regulations. Tervita Corp. was tasked with controlling dust while conserving water in an area known for high winds, Rancho Cucamonga. The firm integrated a tower mounted DustBoss® DB-60™ with a modified shipping container. The result was a drastic reduction in fugitive dust emissions, improved regulatory compliance and better community relations.

In 2012, the Gerdau Corp. chose Tervita to take over operations of the slag processing plant, servicing the company’s long steel mill located approximately 0.25 miles away.

“When we installed the new state-of-the-art crusher, we streamlined the recycling process into a faster operation that is dust-free because of the bag house filtration system,” said Carson Swartz, Operations Supervisor for Tervita. “But the storage and cooling area was a big issue. Whether offloading, churning or moving the slag to the crusher, it’s constantly being disrupted, causing a lot of dust.”

Prior to installing the DB-60, the company tried using the moveable sprinkler irrigation system left in place by the previous operators. Tervita found that the sprinkler system only saturated the surface material, which caused large amounts of runoff and did not properly address the fugitive dust.

The company placed a shipping container in the storage and cooling area. Working with DCT technicians, the container was reinforced with a heavy-duty steel frame and modified to mount a tall steel tower topped by the DB-60 equipped with a 359º oscillation system, making the total height from the ground approximately 28 ft. Inside the container, a touch screen panel is mounted on the wall that allows operators to control the elevation, oscillation arc, booster pump pressure, fan output and water volume. Many of these functions can also be modified outside the container by remote control.

Since the water used by Tervita for dust suppression is non-potable, it is first sent through an in-line 30 mesh, 595-micron filter before being delivered to the booster pump, where the water pressure is raised from 10 PSI up to 160 PSI. Pumped through a hose to a circular brass manifold, the water is forced through 30 atomising spray nozzles, which fractures it into millions of tiny droplets. The mist is then propelled by a powerful 25 HP electric fan that produces 30 000 CFM of airflow through a specialised cylindrical barrel design. Atomised droplets are launched in a cone at an adjustable 0 to 50° angle.

Due to the use of atomised mist, the facility has dramatically reduced the volume of water needed for dust management, making more water available for other parts of production in the plant, thus promoting sustainable overall usage for the entire facility. With fugitive dust levels compliant to SCAQMD regulations, Tervita achieved the goals set for the project and successfully applied a new technology that could be used in other locations and applications.

“As much as we run the machine, we’ve been impressed by how well it’s held up,” Swartz added. “Since the installation, the couple of times we’ve called DCT, they were very responsive and even came out to visit just to see the setup. Their service matches the quality of the equipment.”

Read the article online at: https://www.worldcoal.com/product-news/01092016/tervita-corp-controls-dust-2342/