Egyptalum calciner plant was started up in 1983 ,currently it produces 140000 tpy and that is considered the designed capacity. The type of calciner at our end is rotary hearth type (dish).Calcination of the green petroleum coke is done by heating it to the temperature in the range of 1200 oC – 1350 oC to improve its chemical and physical properties where this process increase coke real density that directly reflects on the calcined coke strength properties , thermal conductivity and specific electrical resistance. The coke type is important especially in manufacturing in prebaked carbon blocks where anode grade green petroleum coke is used after calcining it. Calcined coke quality depends on :- Green coke quality , - Coke heat up , - Bed temperature and residence time. To have a good performance of prebaked carbon blocks , it is should manufactured from the coke that have t quality that attached below.
Physical and Chemical Properties of Calcined Coke
No
|
Properties
|
Unit
|
Value
|
1
|
Sulphur
|
%
|
3.5 Max
|
2
|
Ash
|
%
|
0.45 Max
|
3
|
Moisture
|
%
|
0.05 Max
|
4
|
Volatiles
|
%
|
0.55 Max
|
5
|
Nickel
|
ppm
|
250 Max
|
6
|
Vanadium
|
ppm
|
250 Max
|
7
|
Calcium
|
ppm
|
350 Max
|
|
Iron
|
PPM
|
350 Max
|
|
Silicon
|
ppm
|
250 Max
|
|
Chromium
|
ppm
|
20 Max
|
8
|
Magnesium
|
ppm
|
30 Max
|
|
Titanium
|
ppm
|
10 Max
|
|
Sodium
|
ppm
|
150 Max
|
9
|
Fixed Carbon
|
%
|
99 Min
|
10
|
Vibrated Bulk Density
|
|
|
|
-0.8 + 0.3 mm
|
gm/cm3
|
0.85 Min
|
|
- 0.5 + 0.3 mm
|
gm/cm3
|
0.85 Min
|
11
|
Density in He
|
2.04 – 2.09
|
gm/cm3
|
12
|
Specific electrical resistance
|
µΩm
|
450 - 550
|
13
|
CO2 Reactivity
|
%
|
3 - 15
|
14
|
AIR Reactivity
|
% Minute
|
0.05 – 0.3
|