Polycarbonate Fluidized Bed Drying Experiments And Process Simulation And Optimization

Polycarbonate （referred to as PC） is a kind of comprehensive and excellentengineering plastics and it has been widely used. At present, the domestic productionprocess of polycarbonate still remains at a lower level; the PC drying is a crucial stepin the PC manufacturing process, so this paper on the drying study of polycarbonate isof great significance.In this paper, based on the fluidized and the related theory of fluidized bed, dryingprocess of a laboratory study and the pilot test is deeply studied and understand of thePC drying characteristics, establishing the drying mathematical model of fluidized bed,And use the model to a preliminary design for an annual output of20,000tons ofpolycarbonate fluidized bed drying process and key equipment, the main researchwork are as follows:（1）To design an experiment device and through the PC lab experimental study, usingexperimental data draws the curve of the drying rate, knowing the drying law ofPC fluidized bed and explore the feasibility of fluidized bed drying ofpolycarbonate. The results show that fluidized bed the dryer has goodapplicability in polycarbonate dry, and by the dry data analysis regression, toobtain a dry model parameters K=0.11399, the improved drying model is asfollows:Constant drying rate： M_CDR=0.11399M/d_s(P_sat*（T_s）/RT_s-X_H2OP/RT_SFall drying rate:M_FDR=X-X_eq/x_cr-X_eq*M_CDR（2）Pilot study explores the stability of the continuous test, according to the dryingresults, this experiment once again proved the feasibility of fluidized bed dryingof PC. Cold model experiment study pressure drop and gas velocity experiments in the different particle size of the PC particle. According to the experimentaldata, comparison of several model calculations and experimental values, a fewmodel calculation value and experimental value contrast, given the best ofpolycarbonate particle flow critical flow speed correlation are as follows.（3）Through the established model, a PC powder dryer is optimize designed, dryingmoisture content of from10%to500ppm and the annual output of20,000tonsof fluidized bed dryer. Calculating the operating conditions: inlet Temperature:140℃, the Gas flow:60836.05m3/h; fluidized bed device size:119.38m2, heatexchanger area:1876.02m2.