Screw Conveyor Eliminates Dust Problem Lehigh White Cement in Waco, Texas
Lehigh White Cement Company
Plant Name and LocationLehigh White Cement Company
Waco, Texas
General Description
Since 1969, the Lehigh White Cement plant in Waco, Texas has produced consistent, high quality white portland and white masonry cements. The plant has made many improvements over the years to improve production and reduce environmental impact.
White cement is produced from white Texas lime and other specialized raw materials that are mined in the area around Waco using a very similar process as gray portland cement. Both types of cement have equivalent characteristics of strength, durability and workability. Producing white cement requires precise control of the process parameters to achieve brilliant white color. Lehigh white cement has thousands of uses in commercial and residential construction including, architectural and structural concrete for swimming pools, spas, reflective floors and tile grout.
Design Parameters
- Product Type – Cement Clinker and Dust
- Material Density – 60 Lbs. per Cubic Foot
- Capacity – 850 Cubic Feet per Hour
- Duty – 7 Days a Week, 24 Hours per Day
KWS Advantages
Before KWS Screw Conveyor
The Lehigh White Cement Maintenance Manager contacted KWS looking for a solution for a serious fugitive dust problem at the plant. An existing belt conveyor received cement clinker and dust from five belt feeders and three screw conveyors and transferred the combined bulk materials to a bucket elevator to be elevated to the grinding process. The existing belt conveyor was a maintenance nightmare and created a problem of emitting a large volume of dust. Visibility in the area was less than 10-feet.
An engineer from KWS made several plant visits to measure the existing area and locate the discharge points of every belt feeder and screw conveyor. KWS proposed a very special flared trough screw conveyor that would fit snuggly under the belt feeders and screw conveyors to transfer the cement clinker and dust to the bucket elevator. The proposed screw conveyor would be completely enclosed and dust tight to eliminate the fugitive dust problem.
Special Features
After KWS Screw Conveyor
KWS designed the new screw conveyor with a special flared trough to fit the width of the belt feeder discharge points and under the existing equipment. The screw conveyor trough was flared out wider than normal CEMA standards. The screws were built to handle the abrasive cement clinker with very heavy-duty construction. The carrying face of the screws were hardsurfaced with a special alloy to resist wear and extend service life. Intermediate hangers with bearings were required due to the long length of the screw conveyor.
The hangers were manufactured with structural channel to provide extra stiffness under the weight of the heavy screw sections. The hanger bearings and coupling shafts were sleeved with Stellite for abrasion resistance. The covers were manufactured from heavy gauge material and bolted on 12-inch centers to provide dust-tight construction. The drive unit was designed for cement-duty operations and could start and operate under 100-percent trough-loaded upset conditions.
Testimonial
"The KWS screw conveyor has been operating for over 12 years now with almost no downtime and minimal maintenance. The dust problem has been completely eliminated. Thanks for the help!"
Matt Hummel, Production Engineer – Lehigh White Cement Company
Before KWS Screw Conveyor
Dust accumulates on every surface and air is full of dust. Maintenance, safety and environmental health issues are a continuous issue.
After KWS Screw Conveyor
Dust is removed from all surfaces and air is clean. Maintenance, safety and environmental health issues are eliminated.
