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Chapter 2
2.3 Equipment and unit operations
2.3.1 Reactors
[6, Ullmann, 2001]
The main equipment in multipurpose plants is the stirred tank reactor, which fulfils the
flexibility requirements arising from the varied physical states of the materials being used (e.g.
dry powders, wet solids, pastes, liquids, emulsions, gases).
The vessels are required to withstand a range of process conditions (e. g. temperature, pressure,
corrosion) and are thus usually made of stainless steel, rubber- or glass-lined steel, enamel
coated, or other special materials. The mechanical design of the agitator baffles and cooling
systems is constrained by the need to attach and maintain the rubber or glass lining.
Other characteristics:
• used for both batch and continuous mode, as well as in cascades
• sized up to 60 m 3 (fermentation reactors up to about 1000 m 3 )
• usually dished bottom (reactions may be carried out under pressure)
• equipped with one or more stirrers to ensure the requested mixing degree, heat-exchange
performance, etc.
• jackets or half pipe coils are often fitted around the vessel to provide heat transfer
• wall baffles are installed inside to prevent the gross rotation (“swirl”) of the contents with
the stirrer.
T C
0°C
-20°C
-5°C
T P
Gas inlet
Figure 2.4: Stirred tank reactor (conventional temperature control, left) and loop reactor (right)
Other used reactor types are, e.g:
• loop reactors (closed loop or continuous loop)
• bubble columns (closed loop or continuous loop)
• pipe reactors
• tubular reactors.
24 Dezember 2005 OFC_BREF
Pump
Heat-exchanger