Solid Circulation Rate in Recirculating Fluidized Bed
Publication: Journal of Energy Engineering
Volume 127, Issue 2
Abstract
Recirculating fluidized bed (RCFB) is a spouted bed with a draft tube at the center. This is used for a variety of operations such as incineration, coal and heavy crude oil gasification, grain drying, blending and mixing, etc. Solid circulation rate is an important parameter for any circulation system, and it describes the efficiency of operation. Mathematical models do not always predict the circulation rates accurately. Hence, there is a need to measure the circulation rates directly. Most of the methods (for direct measurement) reported are either costly, involving high expertise and sophisticated equipment, or time consuming. A butterfly valve arrangement can measure the solid circulation rate accurately and quickly. It is sturdy, and the cost/expertise involvement is the bare minimum. Solid circulation rates measured directly using the butterfly valve arrangement are compared with the solid circulation rates computed based on the particle velocity and the operating voidage in the downcomer bed. Solid circulation rates measured directly are in close comparison (mostly within a deviation of 10%) with the computed circulation rates.
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Information & Authors
Information
Published In
Journal of Energy Engineering
Volume 127 • Issue 2 • August 2001
Pages: 51 - 68
History
Received: Apr 26, 2001
Published online: Aug 1, 2001
Published in print: Aug 2001
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