Analysis on the effect produced by the residual moisture content on the
limestone decomposition and the magnetite oxidation. The initial data for the
standard procedure were taken as follows: the rate of gas filtration in the preheating
zone was 1.0 m/s; the depth of the pellets layer was 300 mm; the length of heating zone
was 10 m; the velocity of the carriages was 2.25 m/s; the gas temperature in the
preheating zone was 1050
о
С; the content of residual moisture in the pellets were in
three value sets: 0 %, 1.5 % and 4%; 0 %, 3 % and 7.5%; 0 %, 0 % and 0%. The data
obtained on the limestone decomposition degree is reported in Table 4 while those on
the magnetite oxidation degree are in Table 5.
Table 4 The degree of limestone decomposition depends on the content of the
residual moisture within the pellets layer
Gas temperature,
о
С
1050
1050
1050
Pellet layer
depth, mm
Residual moisture (in pellet layer
depth), %
0
0
0
0
1.5
4
0
3
7.5
Degree of limestone
decomposition, %
100
100
100
300
100
100
100
240
100
100
100
180
60.2
5.1
1.1
120
5.1
0
0
60
Table 5 Dependence of the magnetite oxidation degree on the residual moisture
content in the pellets layer
Gas temperature,
о
С
1050
1050
1050
Pellet layer
depth, mm
Residual moisture (in pellet layer
depth), %
0
0
0
0
1.5
4
0
3
7.5
Degree of magnetite oxidation,
%
95.2
95.2
95.2
300
86.9
86.9
86.9
240
75
75
75
180
57.6
4.2
0.9
120
26.9
0
0
60
Figure 5. Dependence of limestone decomposition degree on the residual
moisture content within pellets layer
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