降低气相流化床聚乙烯装置原料单耗的措施

Reduction of raw material unit consumption in gas-phase fluidized bed polyethylene plant

气相流化床聚乙烯装置原料单耗的影响因素主要为:开、停车与床层再生原料消耗,低负荷下排放气回收系统原料消耗,进退冷凝操作原料损失,产品出料系统(PDS)携带乙烯及脱气塔排放原料损耗,造粒系统产品损耗。采用减少停车次数、更新床层再生频率、优化排放气回收系统、优化进退冷凝操作、调节PDS出料次数、减少精制系统排放、优化粒料损失量等措施可以降低原料单耗。

The main factors influencing the unit consumption in gas-phase fluidized bed polyethylene plant include:raw material consumption during start-up,shut-down and bed regeneration;raw material consumption in vent recovery system under low production load;raw material losses when changing between dry mode and condensing mode;raw material losses due to ethylene carried through product delivery system(PDS)and venting consumption from degassing tower and pellet system.The raw material unit consumption can be reduced by taking the following methods:avoiding frequent shut-down of the plant and upgradingthe frequency of bed regeneration;improving the vent recovery systemand the operation of changing between dry mode and condensing mode;adjusting frequency of PDS discharge;reducing purification system venting and decreasing pellet losses.