Wednesday, June 15, 2011
The gradation of non-coking coal is based on Useful Heat Value (UHV), the gradation of coking coal is based on ash content and for semi coking / weakly coking coal it is based on ash plus moisture content , as in vogue as per notification.
Grades of Coking Coal
Grade
|
Ash Content
|
Steel Grade –I
|
Not exceeding 15%
|
Steel Grade -II
|
Exceeding 15% but not exceeding 18%
|
Washery Grade -I
|
Exceeding 18% but not exceeding 21%
|
Washery Grade -II
|
Exceeding 21% but not exceeding 24%
|
Washery Grade -III
|
Exceeding 24% but not exceeding 28%
|
Washery Grade -IV
|
Exceeding 28% but not exceeding 35%
|
Grades of Non-coking Coal
Grade
|
Useful Heat Value (UHV)
(Kcal/Kg)
UHV= 8900-138(A+M)
|
Corresponding
Ash% + Moisture %
at (60% RH & 40O C)
|
Gross Calorific Value GCV (Kcal/ Kg)
(at 5% moisture level)
|
A
|
Exceeding 6200
|
Not exceeding 19.5
|
Exceeding 6454
|
B
|
Exceeding 5600 but not exceeding 6200
|
19.6 to 23.8
|
Exceeding 6049 but not exceeding 6454
|
C
|
Exceeding 4940 but not exceeding 5600
|
23.9 to 28.6
|
Exceeding 5597 but not exceeding. 6049
|
D
|
Exceeding 4200 but not exceeding 4940
|
28.7 to 34.0
|
Exceeding 5089 but not Exceeding 5597
|
E
|
Exceeding 3360 but not exceeding 4200
|
34.1 to 40.0
|
Exceeding 4324 but not exceeding 5089
|
F
|
Exceeding 2400 but not exceeding 3360
|
40.1 to 47.0
|
Exceeding 3865 but not exceeding. 4324
|
G
|
Exceeding 1300 but not exceeding 2400
|
47.1 to 55.0
|
Exceeding 3113 but not exceeding 3865
|
Grades of Semi-coking and Weakly Coking Coal
Grade
|
Ash + Moisture Content
|
Semi coking grade –I
|
Not exceeding 19%
|
Semi coking grade –II
|
Exceeding 19% but not exceeding 24%
|
Grades of NEC Coal :
Grades
|
UHV (Kcal/Kg)
|
Corresponding
Ash% + Moisture %age
|
A
|
6200-6299
|
18.85 – 19.57
|
B
|
5600 – 6199
|
19.58 – 23.91
|
Source: Ministry of Coal