Inventory of Innovative Indoor Smoke
Alleviating Technologies in Nepal
11
ash is spread on the brick shaped wooden mould which
is soaked in water for 30 minutes before casting bricks.
The prepared paste is then put in the mould and pressed
and levelled. After levelling the paste, the mould with
paste is overturned and the mould is removed slowly.
The prepared block is sun dried for 3 to 4 days.
The construction of the stove starts with preparation of
bricks and soil paste. Soil paste is used to join the bricks
and to fill up the small opening to make it air tight. A
layer of stones is fixed on the floor and a gap of two
inch is maintained between the kitchen wall and stove
wall. The gap is filled either with husk or ash for
insulation. Metal plate or metal rods/rings is placed
around the pothole for additional strength to prevent
the stove from cracking while cooking.
The outlet of the chimney, which is usually made of
metal (varying in shapes and sizes) is extended outside
through the hole of the kitchen wall. The chimney height
is maintained at 5 feet because longer chimney sucks
the flame and hot air thereby reducing the eifficiency
of the stove and the shorter chimney cannot create
sufficient draft. During construction, a small hole is made
on the stove at chimney side to remove soots deposited
in the chimney. Chimney should be bend free to prevent
pressure loss and ensure proper draft.
Chimney should be cleaned off from soots at least once
in 15 to 25 days. As these stoves are not portable,
wind direction should be considered before designing
the kitchen and especially the location of stove.
Ambient air, which contains oxygen for proper
combustion is denser than the smoke. So the kitchen
window should face the wind direction for proper
combustion as well as removal of smoke from the
kitchen as shown in Figure 3.2. Various types of mud-
brick ICS are described below.
Figure 3.2: Kitchen design consideration