Micro-gasification: Cooking with gas from biomass - Amper

Micro-gasification: Cooking with gas from dry biomass
3.3 Feedstock ready to use without major processing
The list of usable feedstock is nearly endless and depends on what is readily available in a
certain location. The following table from FAO gives some ideas, where to look for appropriate
feedstock. Municipal by-products are not recommended for use in micro-gasifiers for
cooking or space-heating, due to high variability and the presence of potentially toxic ingredients,
such as used motor oil and rechargeable batteries.
Source: Unified Bioenergy Terminology ftp://ftp.fao.org/docrep/fao/007/j4504e/j4504e00.pdf, page 9
Agricultural residues are generated in large volumes season by season and often discarded
as waste - not put to use at all. Crop residues are the largest source of non-timber biomass
fuel: straw, stem, stalk, leaves, husk, shell, peel, lint, stones, pulp, stubble, etc. which come
from cereals (rice, wheat, maize or corn, sorghum, barley, millet), cotton, groundnut, jute,
legumes (tomato, bean, soy), coffee, cacao, olive, tea, fruits (banana, mango, coco,
cashew) and palm oil. In the developing world, most agricultural residues that are burnt as
fuel are used in their natural state with some pre-treatment like drying, and cutting, and
compacting in rare. Compared to wood-fuels, crop residues typically have a high content of
volatile matter, lower density and lower burning time. The next table provides a comparison:
Advantages Disadvantages
Agricultural residue is a fuel which is available
free of cost to the poor rural families.
It is also a useful way to dispose of the
crop residues in the field, instead of burning
them in situ.
Agricultural wastes remain safer than LPG
which poses some safety concerns in local
transport and use;
It is easy to handle and transport;
Low impact on women‘s time for harvesting
Agricultural wastes are much easier to light
than wood and charcoal
HERA – GIZ Manual Micro-gasification Version 1.01 January 2011
It is responsible for extreme cases of
air pollution when it is burned in open
fires or traditional improved stoves.
But it can burn well in gasifier stoves.
It is very bulky and has to be carried to
the homes.
The seasonal availability of crop residues
can be limit for its use.
Its burning time is shorter.
Its storage requires more space inside
a house or shelter and protected from
rain.
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