Related Experiment Video
Updated: Aug 7, 2025

Lab-Scale Model to Evaluate Odor and Gas Concentrations Emitted by Deep Bedded Pack Manure
Published on: July 19, 2018
Heat balance analysis for self-heating torrefaction of dairy manure using a mathematical model
Takanori Itoh1, Teppei Ogawa2, Kazunori Iwabuchi3
1Tanigurogumi Corporation, Shiobara 1100, Nasushiobara, Tochigi 329-2921, Japan; Research Faculty of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
None:
A self-heating torrefaction system was developed to overcome the difficulties in converting high-moisture biomass to biochar. In self-heating torrefaction, the ventilation rate and ambient pressure must be set properly to initiate the process. However, the minimum temperature at which self-heating begins is unclear because the effects of these operating variables on the heat balance are not theoretically understood. The present report presents a mathematical model for the self-heating of dairy manure based on the heat balance equation. The first step was to estimate the heat source; experimental data showed that the activation energy for the chemical oxidation of dairy manure is 67.5 kJ/mol. Next, the heat balance of feedstock in the process was analyzed. Results revealed that the higher the ambient pressure and the lower the ventilation rate at any given pressure, the lower the temperature at which self-heating is induced. The lowest induction temperature was 71 °C at a ventilation rate of 0.05 L min-1 kg-AFS-1 (AFS: ash-free solid). The model also revealed that the ventilation rate significantly affects the heat balance of feedstock and drying rate, suggesting an optimal range for ventilation.
Related Concept Videos
Quantifying Heat
Heat Flow and Specific Heat
Mechanisms of Heat Transfer
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant...
Mechanisms of Heat Transfer I
Mechanisms of Heat Transfer II
Mechanism of heat transfer

