A typcical clinker and coal ash and CV is used to predict the impact of changing coal ah levels on clinker quality

1. Impact of Fuel Ash on Clinker Quality
Tom Lowes

2. Impact of Fuel Ash on Clinker Quality
 In the embedded spreadsheet the Bogue calculations for LSF, C3S etc
allowing for SO3 but not include IR are used to predict the change on the
clinker chemistry when changing a coal ash for 20 to 45% for a typical
calciner process
 This shows a drop in LSF of 8% and C3S of 23%, with a drop is one day
strength of 4 Mpa and 2 Mpa at 28 days.
 The spreadsheet is written in such a way that it can be readily modified to
incorporate more than one fuel and hence is ideal to assess the impact of
AFR. However note that these are Bogue and not actual C3S etc, the AFR
ash lumps do not combine easily and can make C3S much lower than
Bogue
 The prediction for a typical clinker and coal ash is on the next slide,
changes are permitted to the red cells, without knowledge of the
password

3. Bogue compound Composition Change with Coal Ash
Current Clinker
Coal Ash Analysis
BS w SO 3
New Climker
%
BS w SO3
SiO2
21.73
LSF
93.2
SiO2
50.00
Coal Ash Current %
Al2O3
4.87
LCF
91.8
AI2O3
19.16
Fe2O3
CaO
3.83
65.02
2.50
1.27
Fe2O3
CaO
MgO
2.00
S/R
A/F
C3S
55.0
SO3
0.79
C2S
20.8
K2O
0.72
C3A
Na2O
F. CaO
0.04
1.00
C4AF
C4AF+C2F
eqNa2O
Total
100.00
20
SiO2
22.89
LSF
85.2
Change in LSF
-8.0
Coal CV current kcals/kg
6500
Al2O3
5.46
LCF
83.9
Change in C3S
-21.3
7.47
15.00
Coal Ash New %
Coal CV New kcals/kg
45
4875
Fe2O3
CaO
3.98
62.97
2.42
1.37
Change in C3A
Change Ash/Clk
1.3
4.1
MgO
2.79
Plant kcals/kg
800
MgO
2.03
S/R
A/F
C3S
33.7
Drop 1 day Mpa
-4.0
SO3
1.40
% Coal Current/Clk
12.3
SO3
0.81
C2S
40.2
Drop 28 day Mpa
-2.2
6.4
K2O
2.79
% New Coal/Clk
16.4
K2O
0.81
C3A
7.7
11.7
0.0
0.51
Na2O
Cl
Total
0.77
0.62
100.00
t extra ash/100 t clk
4.1
Na2O
F. CaO
0.07
C4AF
0.98 C4AF+C2F
eqNa2O
100.00
12.1
0.0
0.60
Total