I.COAL GRADES :
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 cokng 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 |
II.BIO-MASS FUELS:
SNo | Fuel | Approx heating value Kcal/Kg | |
Dry state | |||
1 | Wood | 1500 | 3500 |
2 | Cattle dung | 1000 | 3700 |
3 | Bagasse | 2200 | 4400 |
4 | Wheat and rice straw | 2400 | 2500 |
5 | Cane trash, rice husk, leaves and vegetable wastes | 3000 | 3000 |
6 | Coconut husks, dry grass and crop residues | 3500 | 3500 |
7 | Groundnut shells | 4000 | 4000 |
8 | Coffee and oil palm husks | 4200 | 4200 |
9 | Cotton husks | 4400 | 4400 |
10 | Peat | 6500 | 6500 |
III.FOSSIL FUELS:
1 | Coal | 4000-7000 |
2 | Coke | 6500 |
3 | Charcoal | 7000 |
4 | Carbon | 8000 |
5 | Fuel oil | 9800 |
6 | Kerosene and diesel | 10000 |
7 | Petrol | 10800 |
8 | Paraffin | 10500 |
9 | Natural gas | 8600 |
10 | Coal gas | 4000 |
11 | Electrical (Kcal(KW) | 860 |
12 | Bio gas(Kcal/cu mtr) (12 kg of dung produces 1 cu. Mtr gas) | 4700-6000 |
IV.OILS
LDO (As Per IS 1460-1974) : It is generally used for start up of boiler
Description | Values |
Relative Density @15oC/15oC | 0.85 |
Flash Point PMCC oC min | 38oC |
Kinematic Viscosity CST | 2 to 7.5 |
Sulphur %by weight max | 1% |
Ash weight max | 0.02 |
Gross calorific value Kcal/Kg(Average) | 10720 |
LSHS/HFO (As Per IS 1593-1971) :
It is generally used for Warm up & flame stabilization of boiler.
Description | Values |
Relative Density @15oC/15oC | 0.9579 |
Flash Point PMCC oC min | 66oC (min) 120oC (min) |
Kinematic Viscosity CST | 500 CST max |
Pour Point oC max | 72oC |
Sulphur %by weight max | 4.5% |
Sediment % by weight Max | 4.5% |
Ash weight max | 0.1 |
Water content % Vol .Max | 1.0 |
Gross calorific value Kcal/Kg(Average) | 10000 |
