On-line measurement of the mass flow rate in hot circulating fluidized beds using electrostatic induction charges

An online measuring system which enables the recording of the two-phase flow parameters average velocity of flow and mass flow rate due to the detection of the electric charge of the particles is presented. This fixed noncontact sensor has been installed in the recirculation line of a pilot scale hot circulating fluidized bed that converts methanol to olefins (h=11 m, riserdia.=0.03 m) and works under rough conditions of process temperature up to 450/spl deg/C. The whole dynamic area of the integral mass flow in this hot circulating fluidized bed up to 350 g/min was measured. Further investigations show the applicability up to 600/spl deg/C.<
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