Special Cantilevered Screw Conveyor Columbia Pacific Bio-Refinery in Clatskanie, OR

General Description

The Columbia Pacific Bio-Refinery operates a fuel-grade ethanol production facility near Clatskanie, Oregon. Dried Distillers Grains (DDG) are a byproduct of the ethanol production process and a great, low cost alternative ingredient for animal feed. In the ethanol making process, distillers grains are produced in large quantities and are rich in the protein, fat, minerals and vitamins that animals need. The high nutrient content makes distiller grains an excellent replacement for more expensive corn, soybean meal and di-calcium phosphate ingredients.

Screw conveyors are used throughout the ethanol processing industry for conveying bulk materials such as corn and DDG. Columbia Pacific Bio-Refinery needed a very special screw conveyor for loading shipping containers. The screw conveyor would be unsupported on one end and project into shipping containers. As a shipping container was filled with DDG, it would be moved and the container would be evenly and fully filled with DDG. Columbia Pacific Bio-Refinery contacted KWS because of past experience with special-designed screw conveyors for difficult applications. KWS designed a cantilevered screw conveyor that exceeded the expectations of customer.

Design Parameters

1. Product Type: Dried Distillers Grains
2. Material Density: 52 Lbs. per Cubic Foot
3. Conveyor Capacity: 187,980 Lbs per Hour
4. Duty: 24 Hours per Day, 7 Days per Week

KWS Advantages

KWS has designed and manufactured cantilevered screw conveyors for many different industries. The engineers at KWS have a wealth of knowledge and experience and specialize in designing bulk material handling equipment for demanding applications. The cantilevered section of the screw conveyor for Columbia Pacific Bio-Refinery extended almost 20-feet in order to project inside the shipping containers. KWS verified the design of the cantilevered screw conveyor with Finite Element Analysis (FEA) and improved the design in high stress areas.

Special Features

The sides of the screw conveyor were re-enforced with 8-inch structural channels on both sides of the tubular housing to support the 20-foot long cantilevered section and minimize deflection and sway. The screw conveyor was designed to load 50,000 lbs. of DDG in less than 15 minutes. The new screw conveyor was driven from the inlet end with a 30-horsepower drive unit. KWS selected the drive unit to handle any worst-case upset condition.

CEMA standard screws were selected to minimize cost and for easy access to spare parts. Replacement screws are stocked at a local power transmission distributor. The last screw section extends 2-feet past the end of the trough assembly. The DDG discharges out the end of the screw conveyor and evenly fills the farthest corners of the shipping containers.