Polyethylene Gas-Phase Process

The monomer ethylene is first led through a series of dryers (not shown), mixed with recycle gas, hydrogen, and butylene, and enters the fluidized bed reactor (Rl) at the bottom. A catalyst is added from numerous locations on the side of the reactor (not shown). The reactor operates at approximately 85°C and 20 bar (the temperature depends on the desired grade). The heat of reaction is removed as sensible heat of the gas stream and by the evaporation of the partially liquid reaction mixture. The reactor gas exits the top of the reactor. 

Simplified flow diagram of a gas-phase polymerization process. 

---