Polyolefin autoclave reactor

The simplest reactor is the stirred autoclave reactor. In polyolefin production, this reactor is operated as a CSTR and is used in slurry, bulk and solution processes. The main advantages of this configuration are that the reactor is easy to build and to run, and provides a relatively uniform reaction medium with proper stirring. Its principal disadvantage is that the heat transfer area-to-volume ratio is relatively low and heat removal is, therefore, limited. This limitation is especially difficult to overcome for new plants with increasing production capacity. 

How many of these polyolefin production plants have been installed since the beginning of this industry One way to develop the answer to this question, which we do not pursue in depth here, is to follow the technology licensors. For example, we know that ICI were active in licensing LDPE and that by 1977, they had 23 licensees, and a total installed capacity of 812,000 tons. However, their founding technology was based on the stirred tank reactor (autoclave), and this could not be scaled up in the same way that tubular reactors, developed by others, could. By 1980, ICI had lost the first producer advantage , had not led the way in technology development, and in 1982, exited the PE business. 

Polyolefins are produced in practically all types of reactor configurations -autoclaves, tubular reactors, loop reactors, fiuidized-bed reactors - making them a prime choice for polymer reaction engineering studies. Polymerization may take place in either gas or liquid phases. For liquid-phase reactors, the monomers can be either liquid (as in the case of propylene and higher a-olefins) or dissolved in an inert diluent. Industrial catalysts for olefin polymerization are mainly heterogeneous, but some processes also use soluble catalysts. There are many different types of catalysts for olefin polymerization and they can be used to synthesize polymer chains with very different microstructures and properties. 

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