Pedosphere 25(5): 696--702, 2015
ISSN 1002-0160/CN 32-1315/P
©2015 Soil Science Society of China
Published by Elsevier B.V. and Science Press
| Production of biochar for soil application: A comparative study of three kiln models |
S. MIA1 ,
N. UDDIN2, S. A. Al MAMUN HOSSAIN3,
R. AMIN4, F. Z. METE1 and T.
HIEMSTRA5 |
1Department of Agronomy, Patuakhali Science and
Technology University, Dumki, Patuakhali 8602
(Bangladesh)
2Department of Agricultural Chemistry, Patuakhali
Science and Technology University, Dumki, Patuakhali 8602
(Bangladesh)
3Department of Agricultural Engineering, Patuakhali
Science and Technology University, Dumki, Patuakhali 8602
(Bangladesh)
4Globe Soft Drinks Ltd., Begumgonj, Noakhali-3820
(Bangladesh)
5Department of Soil Quality, Wageningen University,
Wageningen-6700 AA (The Netherlands) |
| ABSTRACT |
| Biochar has potentials for soil fertility improvement,
climate change mitigation and environmental reclamation, and
charred biomass can be deliberately incorporated into soil
for long-term carbon stabilization and soil amendment. Many
different methods have been used for biochar production
ranging from laboratory to industrial scales.However, in countryside
of developing countries, biomass is
generally used for cooking but not charred.~Biochar
production techniques at farmer scale have remained poorly
developed. We developed and tested biochar production
kilns for farmers with a dimension of 50.8 cm × 38.1
cm (height × diameter), using three different setups
for optimizing oxygen (O2) limitation and syngas
circulation: airtight with no syngas circulation (Model I),
semi-airtight with external syngas circulation (Model II)
and semi-airtight with internal syngas circulation (Model
III). A comparative assessment of these biochar production
kiln models was made considering biochar pyrolysis time,
fuel to biomass ratio, biochar to feedstock ratio and
thermogravimetric index (TGI). Among the models, the best
quality biochar (TGI = 0.15) was obtained from Model I kiln
taking the longest time for pyrolysis (12.5 h) and the
highest amount of fuel wood (1.22 kg kg-1 biomass).
Model III kiln produced comparatively good quality
biochar (TGI = 0.11), but with less fuel wood
requirement (0.33 kg kg-1 biomass) and shorter
pyrolysis time (8.5 h). We also tested Model III kiln in a
three times larger size under two situations (steel kiln
and pit kiln). The biochar to feedstock ratio (0.38) and
quality (TGI = 0.14) increased slightly for the larger
kilns. Quality of biochar was found to be mainly related to
pyrolysis time. The costs for the biochar stove and pit
kiln were US$ 65--77, while it was US$ 154 for the large
size steel kiln. Model III kiln can potentially be used for
both cooking and biochar production at farmer scale. |
| Key Words: biomass, farmer scale, feedstock, fuel
wood requirement, O2 limitation, pyrolysis time,
syngas circulation, thermogravimetric index |
| Citation: Mia, S., Uddin, N., Mamun, H., Amin, R., Mete, F. Z. and Hiemstra, T. 2015. Production of biochar for soil application: A comparative study of three kiln models. Pedosphere. 25(5): 696-702. |
| |
|
View Full Text
|
|
|
|
