Preparation And Properties Of Fluidized Bedheat Exchanger Dedicated PTFE/SiO₂ Solid Particles

With the development of modern industrial technology, continuous improvement and innovation in evaporation device. Inert particle fluidized bed evaporator, also kn-own as the vapor liquid solid three-phase flow fluidized bed evaporator is a new type of high efficient evaporation equipment. It has good heat transfer performance, filled with inert solid particles has good prevention and descaling effect and strengthen heat transfer function.Different physical properties of different inert solid particles, the to the destructive effects of the fouling layer and strengthen the effect of heat transfer are also different. The solid particle material of glass, ceramic, PTFE, corundum, quartz sand, etc, are single material, size rang from 1mm⁴mm. Due to the different properties of these particles, in varying degrees of defects and thus developed to meet certain operating conditions of the new inert solid particles, fluidized bed heat exchanger technology further popularization and application has important significance.This study considering the excellent characteristics of the SiO₂ powder and pol-ytetrafluoroethylene（PTFE）, in the PTFE powder adding different content of SiO₂,filling modification, adopts the paste extrusion method to prepare compound solid particles with different different proportion of solid particles, examines the different proportion of solid particles density, hardness and wear situation changes, and applied to the vapor-liquid-solid three phase circulating fluidized bed heat exchanger, further study on different ratio coefficient of heat transfer and flow performance of solid particles, and the suitable operating parameters of new particles in fluidized bed heat exchanger, the practical application of the industry has a certain guiding significance.Experiments show that:adding SiO₂ in PTFE can significantly increase the hardness and reduce friction coefficient of PTFE; When the SiO₂ content of 12%, the composite solid particles used in circulating fluidized bed heat exchanger can make the film heat transfer coefficient increased by 4.7%, improved heat transfer effect is the best; Suitable adding fluidized bed heat exchanger of the particle volume fraction is 4%.