High Temperature Kiln Injection Screw Conveyor

Plant Name and Location

Calgon Carbon Corporation
Gila Bend, GA

Consulting Engineer

Alstom Power, Inc.
Warrenville, IL

General Description

Calgon Carbon, a global leader in the manufacturing of granular, powdered and extruded carbon, needed a solution for feeding granulated activated carbon into rotary kilns in their new reactivation plant. Rotary kiln operating temperatures can exceed 1,800-degrees F and require very special equipment designs that can withstand the high temperature. KWS designed and provided cantilevered injection screw conveyors, which proved to be the ideal solution.

Design Parameters

Product Type: Granulated Activated Carbon
Material Density: 32 to 60 Lbs. per Cubic Foot
Conveyor System Capacity: 165 Cubic feet per Hour
Duty: 24 Hours per Day, 7 Days per Week

KWS Advantages

KWS worked closely with engineers at Alstom Power for over a year to design cantilevered screw conveyors that would meet and exceed the needs of Calgon Carbon. In doing so, we were able to eliminate potential design issues that could have proved to be costly in the field. KWS was able to provide 3D models and AutoCAD drawing to Alstom Power’s engineers to ensure proper layout and fit-up before the equipment’s arrival on-site. We utilized our extensive knowledge and experience in high temperature applications to provide a long-term solution for Calgon Carbon.

Special Features

The injection screw conveyors needed to extend approximately 3 feet into the rotary kiln and withstand elevated kiln temperatures in excess of 1,800ºF. The conveyors were manufactured using 310, 316, and 304 stainless steel components to withstand the high temperature as well as the corrosive environment of the process. The KWS design incorporated a screw that stopped short of the housing discharge to create a natural plug condition at the end of the screw conveyor. This plug prevents heat, gases and fumes from flowing back into the preceding equipment and processes. High-torque drive units were used to push the material plug into the rotary kilns. Most notably the units utilized a KWS custom manufactured 316 stainless steel hanger bearing with Stellite bearing inserts and coupling shaft with Stellite sleeve. These two components were able to add excellence wear resistance and withstand the extreme environment.