Anaerobic Sludge Digestion

This process involves the anaerobic reduction of organic matter in the sludge by biological activity. The methane produced can be recovered and reused for heating and incineration. Four types of anaerobic digesters are commonly used for sludge stabilization. These are standard-rate, standard high-rate, two-stage and separate. These digesters are outlined below and illustrated in Figure 2.

                                      Figure 2: Typical Anaerobic Sludge Digesters