Gr Sprenger Engineering Case Histories

Case History:
Cement Kiln Dust and Waste Fuel Incineration

Problem:
High QC/QA CKD Sample Required for EPA

A cement manufacturer in Texas completed their Trial Burn under the new Boiler and Industrial Furnace regulations in order to secure a permit to burn waste fuel in their kilns. Cement kiln dust (CKD), produced as a by-product of the process, must be sampled and analyzed for metals and organic constituents in order to comply with permit requirements. Sampling procedures consisted of taking a grab sample by hand from the process at a transfer point between a dust collector hopper screw conveyor and a bucket elevator. EPA sampling requirements demand a high level of quality control and quality assurance which caused the need to provide a better system of collecting a representative sample from the process.

Solution:
A Sprenger Continuous Solids Sampler was designed for installation between the bucket elevator and dust bin. The profile of the Sprenger Sampler allowed the device to be installed in the bucket elevator discharge chute without any major structural changes or additional return conveyors. The full CKD flow (2 to 5 tons per hour) passes through the Sprenger Sampler and drops to the CKD bin by gravity. A continuous sample stream of less than 1 pound per hour is collected by the sampler and stored in a closed five gallon container. The manual sampling procedure was eliminated during periods of waste fuel incineration.

Case History:
Cement Clinker Sampler

Problem:
High Abrasion, High Temperature and Unreliable Product Quality

Holnam, Inc. operates a large-scale cement plant near Fort Collins, CO. Strict Quality Control and aggressive efficiency standards demanded that the plant be able to tightly control their kiln operations. Normal samples collected from the discharge of the clinker cooler, as in most cement plants, gave only a rough and delayed approximation of clinker quality. A better method of collecting a representative sample of clinker as soon as possible after discharge from the kiln was needed.

Solution:
A Sprenger Continuous Solids Sampler, with specially designed refactory wear components, was installed beneath the second stationary grating of the clinker cooler. The plant installed a relatively small drop chute from this grating through the wind box. All of the material falling through this drop chute passes through the sampler. The sampler takes a small, representative cut of the clinker material the remainder of which reports to the dust conveyor. Since the sampler has no moving parts, maintenance has been minimal since installation in early 1997. The result has been that the standard deviation of clinker quality has been reduced by a factor of two.