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INDIAN SCENARIO

4.2.1.1
CHARACTERISTICS OF INDIAN COAL

The most important criteria is the quality of Indian coal. The different grades of coal produced
in India are shown in Table 14.

TABLE 14
Characteristic Features of Indian Coal [102]

Useful heating value Gross Cal Value
Grade Ash %
Kcal/kg Kcal/kg
A >6200 <19.5 >6454
B 5600-6200 19.6-23.8 6049-6454
C 4940-5600 23.9-28.6 5597-6049
D 4200-4940 28.7-34.0 5089-5597
E 3360-4200 34.1-40.0 4324-508
F 2400-3360 40.1-47.0 3865-4324
G 1300-2400 47.1-55.0 3113-3865

Much of the Indian coals are difficult to wash and the nature of the coal is also non coking
type. Although there are several coal based plants for methanol and/or DME in China but
the quality of Chinese coal is much better than Indian coal. The Gross Calorific Values for
most of the Indian coals vary in the range of 3500 to 4000 kCal/Kg while for the coal which is
imported in India from Indonesia the range is between 5400 to 6500 kCal.kg [102]. This clearly
implies that for processing the same quantity of coal, the chemical output in weight basis will
be almost half of what would have been expected from good quality coal. Since the plant cost
is directly proportional to the amount of coal processed, the investment cost for Indian coal
based methanol or DME plant will be proportionately higher. Moreover there is practically no
commercial experience in the world to process non coking coal with 50% ash for methanol or
DME production.
The Table 15 indicates the additional cost for using low grade coal for gasification.

TABLE 15
Additional Cost for Processing Low Grade Coal [104]

Increased
Process Units Increased Ash Increased Sulfur
Moisture
Fuel Preparation + +
Gasifier + +
ASU + +
Slag Handling +

Heat Recovery ? +
Sulfur Removal +
Steam Cycle +

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