Low‐density polyethylene vessel reactors: Part I: Steady state and dynamic modelling

By the use of a perfectly mixed model and an imperfectly mixed one for lowdensity polyethylene vessel reactors, we show that increases in the initiator consumption with polymerization temperature are due to mixing limitations at the initiator feed. With all its parameters independently estimated, the imperfectly mixed model provides an excellent agreement with experimental data for several initiators, feed flow rates and polymerization pressures. In the temperature region of industrial interest for each type of initiator, the open‐loop reactor dynamics drastically change from open‐loop unstable, at low temperatures, to open‐loop stable at high polymerization temperatures.