Heat Transfer Characteristics and Pressure Drop in a Horizontal Circulating Fluidized Bed Evaporator

Abstract

A vapor–liquid–solid horizontal circulating fluidized bed evaporation setup was constructed to study the thermal-exchange properties and pressure change. The influences of the operating variables, including the amount of added particles, heat flux, and circulating flow velocity, were systematically inspected using resistance temperature detectors and pressure sensors. The results showed that the heat transfer effect was improved with the increase in the amount of added particles, circulating flow velocity, and particle diameter, but decreased with increasing heat flux. The pressure drop fluctuated with the increase in operating parameters, except circulating flow velocity. The enhancing factor reached up to 71.5%. The enhancing factor initially increased and then decreased with the increase in the amount of added particles and circulating flow velocity, fluctuated with increasing particle diameter, and decreased with increasing heat flux. Phase diagrams showing the variation ranges of the operation variables for the enhancing factor were constructed.

Keywords

Heat transfer characteristics / Pressure drop / Horizontal circulating fluidized bed evaporator / Vertical heights / Fouling prevention and removal

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