REACTOR DESIGN Reactor Selection Process Design Mechanical Design Heat Calculation Specification SheetSELECTION OF REACTOROur system is gas-liquid system. We select a batch stirred tank reactor. This is due to the following reasons: We need to have the bio mass and molasses in contact with each other for a long time. Need to mix the nutrients, bio mass and molasses well together. Visited MURREY BREWERY INDUSTRY RAWALPINDI where batch process was taking place. Concentration and temperature of the species is uniform through out. The following table tells us that a stirred batch reactor is common for gas-liquid systems.