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PROBLEMS & ISSUES TO BE ADDRESSED

The utility and feedstock consumption for production of methanol depends on the process
scheme, feedstock type and export or import of power. Estimated raw material & utility
consumptions for production of 1 MT of methanol from different hydrocarbon feedstocks
and processes is shown in Table 19. It should be noted that autothermal reformer consumes
more gas but exports power with lower consumption of steam and water as compared to
that of steam reformer. Therefore, this option is more economical for gaseous hydrocarbon
feedstocks. However, these figures are only indicative because the calorific value of coal is
varying widely and the purity of methanol is also not fully defined.

TABLE 19
Feedstock & Utility Consumption per MT for Methanol

Per MT of Methanol Methanol from NG (Auto Methanol from NG
Inputs
Methanol from Coal Thermal Reformer) (Steam Gas reformer)
Coal MT/MT 1.72 - -
NG SM3/MT - 842 795
Oxygen MT/MT 1.07 0.72 -
Steam MT/MT 0.168 0.138 0.9 to 0.98
Power KWH/MT -- (-) 0.25 65 to 68
Water M3/MT 15 to 18 4 to 5 6.5 to 6.7

The cost of a large scale IGCC plant based on coal gasification, oxygen firing and carbon
sequestering with provision for producing both methanol and power is of the order of 2000
Euro (approx. 1,40,000 INR) per KW of power [126]. The overall energy efficiency for coal
conversion is about 50 to 55%. With time, the efficiency is increasing due to better design
and the investment cost is also reducing. On an average about 1Ton of coal is required to
produce little over 2 MW of power. When I Ton of coal is converted to methanol or DME via
IGCC, about 500 Kg of methanol or 350 Kg of DME is produced. Most of the IGCC based
methanol plants also produce some power for its internal consumption and some surplus for
the grid. The investment cost depends mostly on the location, feed characteristics and the plant
sophistication level. There is wide variation in product mix, technology selected, operating and
emission control strategy, feedstock type etc.
In Assam, one gas based plant for 500 TPD of methanol at a cost of Rs.1028 Crores is being
considered. However, this plant is based on Natural Gas. West Bengal Government is also
considering a plant for producing 1500 Ton of Methanol per day and fuel gas from Coal.

5.1.2
ECONOMIC FEASIBILITY FOR BIOMASS BASED PLANTS
A feasibility report was prepared by Envitech recently for 6 MW Biogas power Plants (in 3
Blocks) for 135,000 MT/year of manure and agricultural residue/forage crops. About 45 million
KWh Green power exported to the grid plus solid and liquid fertilizer for fertilizing 72 Hectares.
This plant would cost about 10 Million Euro (approximately Rs. 100 Crores) [111].
It is expected that the share of biomass in the world will soon be of about 60% of the renewable
power produced, which will be about 20% of total energy produced from all sources. It is thus
worth looking into this option to produce renewable electricity. This electricity could be used to
generate hydrogen for conversion to methanol with carbon dioxide. Both these technologies
are available, and the cost is much lower with all the associated environmental benefits [112].
The production of biogas by anaerobic digestion (biomethanation) is the cheapest way to
convert a major portion of organic wastes. Therefore, before using the biomass for gasification,
possibility of conversion to biogas through biomethanation must be explored. Use of this biogas

82 Methanol and DME Production: Survey and Roadmap | 2017