Parametric performance studies on fluidized-bed heat exchangers. Task 1: Fouling characteristics

Analyses and experiments are being performed to investigate the heat transfer performance of single and multistage shallow fluidized beds for application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. Tests were conducted to investigate the effects of liquid condensate fouling on fluidized bed heat exchanger performance. Liquid condensates used in these tests were water and glycerol (which is more viscous than water). The tests showed that fluidized bed heat exchanger performance is degraded by condensation within the bed and the degradation is caused by bed particles adhering to the heat exchanger surface, not by particle agglomeration. Liquid condensate did not continuously build up within the bed. After a period of dry out, heat transfer equal to that obtained prior to condensation was again obtained.