A chemical (Figure 1.1a) or a biochemical (Figure 1.1b) process consists of an upstream, reactor and downstream sections. The upstream section in a chemical plant will consist of the raw materials preparation. Whereas, the upstream section in a biochemical process consists of facilities for the preparation of micro-organism and media, sterilization of raw materials
and inoculation of the micro-organism. The reactor section is the fermentor or a reactor/bioreactor and the associated machinery. An aerobic fermentor may contain air purification, compression and injection systems. The product is prepared in the reactor section. The downstream in a biochemical or chemical process section may consists of the following:
1. separation, recovery, and recycle of micro-organisms, enzymes, catalysts (metal, heterogeneous or homogeneous catalyst, if present) or raw materials,
2. recovery of the product, 3. purification of the product to the required degree, and 4. effluent treatment and disposal.