Classification of bioreactors

Bioreactors can be classified on the bases of: 

1. Mode of operation: 

A bioreactor may be classified as batch, fed batch or continuous reactor on the bases of mode of operation. 2. Mode of flow of fluids: A bioreactor may be classified as CSTR bioreactor (continuous flow stirred reactor-the content of the bioreactor is ideally mixed), bioreactor with piston flow and bioreactors with non- ideal flow of fluids (cascade of ideal mixtures, dispersed flow of fluids) on the bases of mode of flow of fluids. The quality of flow of fluids significantly influences the rate of grow of cells and the degree of conversion of substrate and consequently, the yield and selectivity of the products. 

3. Number of phases treated into the bioreactor: we can distinguish bioreactors as homogeneous bioreactors (e.g. one phase tubular bioreactor with enzyme diluted in the liquid substrate) and heterogeneous bioreactors (e.g. two phase solid-liquid bioreactor like the column type bioreactor with immobilized enzyme and liquid substrate) and/or three phase bioreactors with submersed culture: gas (air bubbles)-liquid (substrate)-solids (cells).