Microbiological heating
Initial temperature increases in stockpiles of hay, woodchip, etc. have usually
been attributed to microbial actio_n (Armstrong, 19?3). Conflict remains as to the
division between microbiological and chemical heating and the significance of
the latter at low temperatures. Experimentation with compost, soils etc. has determined the numbers of active microbial species which are present in these media.
Calculations indicate that if the corresponding numbers of active microbial
species were to be established in bagasse stockpiles, heating rates of the order of
20 “C per day may be achieved (Ashbolt, 1984). However consideration of the
limited published data for cell counts in hay, Woodchip and bagasse suggest that,
in the initial stages, microbiological heating rates of less than 2 °C per day would
be sustained (Gray, 1984). -