Understanding the factors affecting the self-heating process of compost piles: Two-dimensional analysis


  • Thiansiri Luangwilai Navaminda Kasatriyadhiraj Royal Thai Air Force Academy
  • Harvinder Sidhu Applied and Industrial Mathematics Research Group (AIM), School of Science, University of New South Wales at the Australian Defence Force Academy
  • Mark Nelson School of Mathematics and Applied Statistics, University of Wollongong




compost, self-heating, spontaneous ignition, moisture, air flow, compost pile geometry


Industrial compost piles contain large volumes of bulk organic materials. Normally, there are two main heat generation processes—oxidation of cellulosic materials and biological activity within the compost pile. Biological heating occurs at a lower temperature range, but it may `kick-start' the oxidation reaction. Nevertheless, biological heating is desirable and is a key component in composting operations. However, there are cases when the temperature within the compost piles increases beyond the ignition temperature of cellulosic materials which can result in spontaneous ignition. This investigation considers the self-heating process that occurs in a compost pile using a two-dimensional spatially-dependent model incorporating terms that account for self-heating due to both biological and oxidative mechanisms. The variation of temperature distribution within different pile geometries is examined.


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