ABSTRACT
Substrate biodegradability was used in previous equations to determine the amount of substrate energy available to drive the composting process, the requirement for additional energy amendments, the stoichiometric oxygen demand, the air demand to remove heat from the process, and the final product mass. This chapter aims to review available data on substrate biodegradability, discuss alternative techniques for measuring degradability, and present experimental results using respirometric techniques. It reviews a case study where laboratory testing of substrate degradability helped in solving a rather severe operating problem. Substrate biodegradability is an important parameter that should be determined during design of any composting facility. Degradability of the feed substrates determines: the quantity of available heat, which is the major energy input driving the composting process, the mass balance including the quantity of final product and the air supply needed for heat removal, and the stoichiometric oxygen demand.
