40
Inventory of Innovative Indoor Smoke
Alleviating Technologies in Nepal
4.2 Beehive briquettes
Photograph 4.2: Dried beehive briquettes
Source: RONAST
Year of dissemination
Cost
Quantity produced
Manufacturing process and technical
description
Research started in 1980s which was then promoted by ICIMOD.
JICA and former RONAST were also involved in research. IDS
replicated and disseminated briquettes in 2004.
NRs. 6 at production site (in 2004), cost varies with retailers. In
Kathmandu valley the price ranges from NRs. 12 to 15.
Around 13,000 kg.
Banmara has tremendous negative impact on forest as it can not
be used as fodder and foliage for cattle. On the other hand, it has
low moisture and ash content suitable to produce fuel. Besides
banmara, the raw materials used for beehive biomass briquette
are clay, dung and lime. Clay has good binding and compaction
property - alumino-silicate compound and is named ‘benthonite
clay.' Dung contains digested/undigested starch which has both
binding property and fuel value, and mixing with other materials
possibly enhances fuel quality. Lime or calcium oxide (CaO) is
exothermic in nature which emits heat and diminishes the emission
of oxides from nitrogen and sulphur dioxide acting as a disulfurising
agent. It is also a good additive to lower smoke emission from fuel
(Beehive Briquette Project, 2005). Banmara sun dried for a week
is cut into one foot long pieces which are then charred in a drum or
pit. The recovery of charcoal in pit burning is comparatively better.
Once the moisture is driven out and sufficient temperature is
reached inside the pit, it is covered with a plain metallic sheet to
prevent further supply of air which is a necessity for charring process.
It is left overnight to cool and the formed charcoal is powdered by
either electric or manual driven grinder machine on the following
day and is mixed in different proportion with dung, clay, and lime.