Abstract
In this paper, we describe the use of various bulking agents for recovering heat from a vacuum-aeration composting system; in addition, we discuss the probability of utilization of the heat generated during composting processes. The materials were composted for 28 days using a 430 L reactor, and the heat recovered from vacuumed gases was calculated. Composting was carried out by employing four commonly used materials and two materials that are not commonly used, namely, rock wool waste generated from horticultural activities and spent mushroom waste. Heat energy of 229–601 MJm-3 was recovered from vacuum-aeration composting; 90 –162 MJm-3 of this recovered energy was obtained as utility energy. The heat recovered from vacuum-aeration composting was 13 % of the heat recovered in the case of combustion reaction.
