Generation and control of static in gas-phase polyethylene reactor
The main reason of reactor shutdown is the agglomeration caused by static during the industrial production in gas-phase polyethylene plant.The main factors that affect the generation of static electricity were analyzed,including the properties of resin particles,fluidized bed operating parameters,impurities in the system,and electrification of raw and auxiliary materials during transportation.The ways to reduce the charge amount in the fluidized bed were combined with theoretical and practical production experience to propose the control methods which include forming a smooth coating on the inside surface of the reactor,thoroughly displacing the reactor and pre-treating the bed during start-ups,operating in condensed mode,controlling the concentration of the impurities,operating the reactor under stable process parameters,and adding continuous additives.The methods reduce the agglomeration caused by static in the reactor,which is beneficial for the long-term operation of the plant.