Chapter 12 - Dry Anaerobic Digestion of Wastes: Processes and Applications

Abstract

Dry digestion technology for biogas production is an innovative approach for treating organic solid wastes; it requires less added water without impairing the fermentation process. Dry anaerobic digestion processes are more robust, flexible in acceptance of feedstock, and better options for treating fiber-rich feedstock than conventional technologies. This new technology has been challenging for the industries despite its numerous benefits. Processes involved in the dry digestion of organic solid wastes and the major challenge of handling, pumping, and mixing of the highly solid and viscous waste streams in the bioreactors are addressed in this chapter. An appropriate inoculum-to-substrate ratio, generation of microbial culture adapted to the feedstock, suitable bioreactor design technology to enhance mixing, and process monitoring and control are the criteria for higher efficiency (reduced retention time and maximum biogas production) and are critical to the effective implementation of dry digestion biogas plants.