Fluidised bed tube bundle heat exchanger - designed to avoid solids backflow and dead zone, contg. mostly riser tubes for solid-laden medium

摘要

In a heat exchange appts. in which most of the tubes are riser tubes for a solids-laden medium to be treated and the rest of the tubes are return tubes for fluidised solid particles for supply to an internal circuit, the novelty is that (a) the appts. has a medium entry chamber (1) contg. an internal container (13) which has a central outlet (16) in its base (15) and which can hold the entire fluidised material (10); (b) a gap (14) is formed between the internal container (13) and the housing (7) of the appts.; (c) a medium inlet (2) is located at the side of the entry chamber (1) and is connected to the outlet (16) by a pipe (22) which passes through the sidewall of the internal container (13); and (d) openings (17) are provided around the outlet (16). USE/ADVANTAGE - The appts. is a fluidised bed heat exchanger for heating or cooling media which tend to form crusts or deposits. It has improved shutdown and operating characteristics, i.e. backflow of solid particles is reliably and simply prevented on shutdown or system failure and, after re-starting, the entry chamber is maintained practically solids-free during continous operation.