Type of Reactors

 

Reactors In Manufacturing Industry:

  The reaction stage is the heart of a chemical manufacturing process. In the reactor the raw materials are brought together under conditions that promote the production of the desired product; invariably, by products and unwanted compounds (impurities) will also be formed.

Homogeneous reactions are those in which the reactants, products, and any catalyst used

 

Heterogenous Reactions : two or more phases exist,

Liquid-liquid: immiscible liquid phases; ex: emulsion polymerizations.

Liquid-solid: with one, or more, liquid phases in contact with a solid. The solid may be a reactant or catalyst.

Liquid-solid-gas: where the solid is normally a catalyst

Gas-solid: where the solid may take part in the reaction or act as a catalyst.

Gas-liquid: where the liquid may take part in the reaction or act as a catalyst.

 

1.   Batch Reactor :

In a batch process raw materials added into reactor in sequence; then reaction proceeds, the compositions changing with time, and the reaction is stopped and the product withdrawn when the required conversion has been reached.

 

2.     Continuous Reactor:

All the reactants are fed to the reactor and the products withdrawn continuously; the reactor operates under steady-state conditions. Continuous production will normally give lower production costs than batch production, but lacks the flexibility of batch production.

 

3.   Stirred tank reactor: Used for Homogeneous liquid-phase

Stirred tank (agitated) reactors consist of a tank fitted with a mechanical agitator and a cooling jacket or coils. They are operated as batch reactors or continuously.

4.   Tubular reactor:  used for homogenous liquid phase, pipeline reactor used for homogenous gas phase

 Ex: Manufacturing of Trifluoro Acetic acid ( HF + TCAC )

5.   packed bed Reactor:

Packed bed reactors are very versatile and are used in many chemical processing applications such as absorption, distillation, stripping, separation processes, and catalytic reactions. 

6.   Fluidized bed reactor: Type of reactor device that can be used to carry out a variety of multiphase chemical reactions. 

 

 Design safety check list

(a) Exothermic heat of reaction

(b) Temperature control emergency systems

(c) Side reactions dangerous?

(d) Effect of contamination

(e) Effect of unusual concentrations (including catalyst)

(f) Corrosion

 

 

Selection of Reactor MOC in Manufacturing Industry:

 

Reactor MOC selection will be done based on nature of reaction i.e., Acidic  or Basic

 

	Acidic	Basic
Homogeneous	Glass Lined /Hastelloy	SS/Hastelloy
Heterogeneous	Glass Lined /Hastelloy	SS/Hastelloy