- modifying the combustion-air supply, particularly if a combustion-air controller is provided -
increasing the size of the jet openings (avoid if possible) The aim of all such measures is to
obtain a stable, compact, slightly bluish flame.
Table 5.16: Comparison of various internationally marketed biogas burners (Source:
OEKOTOP, compiled. from various sources)
Type of burner¹
Peking No. 4/PR China (3)
Jackwal/Brazil (1)
Patel GC 32/ludia
Patel GC 8/India
KIE burner/Kenya (2)
Number of
flames
1
2
2
1
2
Gas
consumption
200 l/h
2 X 1501/h
2 X 2501/h
2301/h
?
Burning
properties
+
++
o
+
+
Handling
o
+
++
++
++
++ very good +good o average
1 Number of burner shown in figure 5.31
Fig. 5.31: Various types of biogas burners. 1 2-flame lightweight burner (2 X 1501/h), 2 2-flame
stable burner (2 X 2501/h), 31-flame burner (200 I/h) (Source: OEKOTOP)
Gas cookers/stoves
Biogas cookers and stoves must meet various basic requirements:
- simple and easy operation
- versatility, e.g. for pots of various size, for cooking and broiling
- easy to clean
- acceptable cost and easy repair
- good burning properties, i.e. stable flame, high efficiency
- attractive appearance
A cooker is more than just a burner. It must satisfy certain aesthetic and utility requirements, which
can vary widely from region to region. Thus, there is no such thing as an all round biogas burner.
Field data shows that 2-flame stable burners are the most popular type (cf. fig. 5.31).
Table 5.17: Biogas consumption for cooking (Source: OEKOTOP, compiled from various
sources)
To be cooked:
11 water
51 water
31 broth
1/2 kg rice
1/2 kg legumes
Gas consumption
30-40 l
110-140 l
~60 l/h
120-140 l
160-190 l
Time
8-12 min
30-40 min
~40 min
~60 min
68