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U.S. Department of Energy
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Applauding the performing seal

Journal Article · · Chemical Engineering (New York); (United States)
OSTI ID:7206948

Whether the culprit is a pump, valve, compressor, or flanged pipe connection, the end result is the same: process-fluid leakage damages the environment and is costly to operators, in terms of lost product, lost production due to downtime, and the replacement of damaged process equipment. Hard-to-handle fluids, such as abrasive slurries of coal and flyash, can damage the seals that contain them, allowing potentially harmful fluids to escape. Even more insidious is the often-invisible escape of volatile organic compounds (VOCs) from equipment that handles liquid petroleum, petroleum by-products and chemicals. This paper reports that seal manufacturers are using their ingenuity to minimize the escape of liquid and gaseous emissions. One approach uses the power of magnetic attraction to create a seal along a rotating pump shaft by positioning magnetic fluids there. Ferrofluidics Corp. starts by creating a magnetic fluid - essentially a colloidal suspension of ultrafine magnetic salts dispersed in a carrier fluid - which is then used as a liquid O-ring seal in conjunction with a mechanical seal. The seal apparatus consists of a doughnut-shaped sandwich (centered around the pump shaft), with a permanent magnet as the middle layer, and a washer of magnetically permeable material on either side.

OSTI ID:
7206948
Journal Information:
Chemical Engineering (New York); (United States), Journal Name: Chemical Engineering (New York); (United States) Vol. 99:3; ISSN 0009-2460; ISSN CHEEA
Country of Publication:
United States
Language:
English