Utilization of bagasse in brickmaking
Practical Action
Table 1: Type and quantities of bricks produced at Kurmuta.
Product
Grade 1 bricks
Grade 2 bricks
Over burnt
Losses
Outer layer (grade 3)
Total bricks in kiln
Wood fired
Number
35700
9000
2850
1450
6000
55000
%
64.91
16.36
5.18
2.64
10.91
100.00
Bagasse fired
Number
42040
9520
3470
970
7000
63000
%
66.73
15.11
5.51
1.54
11.11
100.00
Table 2: Results of laboratory tests
Sample
Bag. blocks
Loose bag.
Miskit stem
Miskit root
Cow-dung
Green brick
Loose clay
Moisture
%
6.73
9.41
14.94
6.80
4.02
3.34
2.84
Volatile
%
62.41
66.23
76.25
72.22
47.93
Fixed
Carbon
27.99
29.34
21.93
25.81
7.3
Ash
Content %
9.60
4.42
1.82
1.97
44.77
Cal.
Mj/kg
Value
18.66
19.17
19.71
19.54
12.81
Table 3: Comparison of costs of dung and loose Bagasse with total production costs
Particulars
Internal fuel cost (LS)
Tunnel fuel cost (LS)
Tot. Production cost (LS)
Internal fuel %
Tunnel fuel %
Int. + Tunnel fuels %
Dung
43000
913920
3771339
1.14
24.23
25.37
Kiln 1
277388
337341
2441768
11.36
13.82
25.18
Kiln 2
317735
551317
2772749
11.46
19.88
31.34
Laboratory tests
Table (2) shows results of tests carried out by the Institute of Energy Research in Soba,
KhaI10um on fuel and clay samples.
Fuel Costs
Table (3) compares cost of energy between using bagasse and cow-dung as internal fuel in the
bricks. The column headed "Dung" refers to data collected from an earlier firing of a kiln of
capacity 140000 bricks, containing cow-dung, fired with wood. Kiln 1 and Kiln 2 refer to firings
with wood and bagasse blocks as tunnel fuels respectively and containing loose bagasse as the
clay additive,
In and around Kassala most brickmakers fire their kilns only with wood and do not add any fuel
to the day. The cost of fuel is then 50-60 % of total production cost. Reduction of this
percentage is an important objective.
From table (3) it can be seen that even though cow-dung is a very cheap fuel, using it as a brick
additive does not result in any reduction in the proportional total cost of fuel compared with
using the more expensive bagasse. However, with using bagasse blocks in the firing tunnels
instead of wood there is some increase in the proportional total fuel cost. Significantly, in each
case total energy cost compared to total production cost is below the disturbingly high
percentage of 50 – 60.
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