The Kennecott Smokestack is a 370.4 meter (1,215 ft) high smokestack west of Magna, Utah. It was built in order to spread the exhaust gases far away from the area of the Kennecott smelter for copper. In 1974 (the year it was completed), environmental rules were such that waste gases could be released in large quantities as long as they were diluted. At that time, up to 48,000 pounds per hour of sulfur dioxide were released. The stack remains as a monument of that time and is still used to exhaust remaining gases after a thorough recovery/scrubbing operation. In 1995 a much cleaner smelter of new design was built in cooperation with the Finnish company Outokumpu. Only a few pounds per hour are now released. The company produces and sells approximately one million tons per year of sulfuric acid made from the formerly released gas.The acid recovery plant was built by a division of Monsanto Corporation. This plant is also designed to recover waste heat from the process to produce electrical power.
The stack is 120 feet (37 m) in diameter at the bottom and rises directly from the ground. A large glass fiber reinforced plastic duct passes up the stack and carries gases to the top. The top can be accessed by a Swedish-built elevator that crawls up a gear track on the inside surface. It takes 10 minutes to ascend the stack. It is not open to the public, but those few who have been at the top are privileged with a magnificent view of the adjacent Great Salt Lake and Oquirrh Mountain Range.
The Kennecott Smokestack is the tallest free-standing structure west of the Mississippi River and the fourth tallest smokestack in the world.
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