Malt House #5 - Shakopee, Minn.
Rahr Malting Co.
Seven Wonders of Engineering in Minnesota Award for Distinguished Engineering
Achievement - 1995 Minnesota Society of Professional
Engineers Minnesota Award of Excellence, "$20 Million and Over" Category - 1994 ABC
This project was the first vertical tower in North America with both germination and kilning capabilities. It is unique because all processes are in one building rather than having them separated into multiple buildings. It is also one of the first round malt house facilities in the country. The facility uses 300 tons of barley each day to produce malt for the brewing industry.
The 270-foot-tall slipformed structure and its equipment are impressive. The interior tower floors are cast at grade and post-tensioned after the concrete achieved a specified minimum strength. Each floor, weighing over 2,000,000 pounds, was lifted in place with six cable jacks. The clear span of each of these floors is 79 feet and supports a live load of barley and water of over 1,000,000 pounds while deflecting only one inch.
Combined, the fans for the malting process have over 3,000 horsepower. The design of this malt house utilizes kiln fans that are placed on the cool side of the kilns, instead of the traditional hot side. By placing the fans on the cool side, the fans could be reduced in size by 3-1/2 percent and could be constructed of carbon steel instead of stainless steel. Although the fans have been reduced in size, they are still over 13 feet tall and weigh over 21,000 pounds.
In addition, Ibberson performed engineering and construction management on two other malt houses, increasing capacity by 20%. Rahr’s overall malt production from all five malt houses is 24,000,000 bushels of malt annually.