Monitoring and control of anaerobic digesters treating industrial effluents

Increasing charges by the private utilities for the treatment of industrial waste water are making on-site effluent treatment more attractive. On-site anaerobic digestion is increasingly being used by food processing factories as a cost effective solution to waste liquid waste disposal. Discharge of treated effluent to sewer or water course requires compliance to a maximum admissible concentration (MAC) value, therefore, there is a need for careful control of on-site waste water treatment. This research investigates the treatment of effluent from instant coffee production. This results in a liquid waste that contains recalcitrant and toxic compounds formed during the roasting process. This waste varies in strength and composition according to the different processes that are performed in the manufacture of instant coffee. Anaerobic filters are particularly attractive for wastes containing recalcitrant or inhibitory compounds requiring a long sludge age. Therefore, this study was aimed at firstly investigating the treatability of coffee waste, using anaerobic filters; and secondly monitoring and control of the digestion process in order to maintain a constant effluent quality. [Continues.]