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PROCESS & TECHNOLOGY FOR METHANOL AND DME

FIG. 2

Co- Production of Chemical & Power [3]

Air Air Separation Nitrogen
Unit
Electric Power
Gas Turbine
Syngas
Coal Gasification Syngas Steam/BFW
Island treatment HRSG
(CO shift)
Slag/Filter Cake
Steam Turbine
Sulphur Sulphur Acid Gas Clean Syngas
Recovery Unit Removal

CCS code
Methanol
CO drying and Methanol Plant
Utilities 2
compression
CO
2

At this point it is worth mentioning that several reports are available on coal/biomass or
municipal solid waste gasification with plasma. The biggest advantage here is that the molten
slag, which comes out of plasma gasifiers, typically operating at 3000 C, are vitreous when
0
solidified. Hence no toxic chemicals leach out from the vitrified mass. Also the overall power
requirement is quite low, compared to incineration [4, 5, 6, 7].
Considering the quality of Indian coal, fluid bed gasifiers with high pressure operation are
most suitable for immediate consideration, while for long term plans, we may explore the
development of plasma gasifiers.

2.1.2.2

SYNGAS FROM BIOGAS
Biogas is the product from digestion of biodegradable non cellular material such as food or
animal waste, including sewage sludge. The average composition of the biogas from anaerobic
digester is about 65 +/- 10% methane; the balance is carbon dioxide with a little hydrogen. The
carbon dioxide may be separated and the methane is used as natural gas in the reformer. In
view of the fact that the biogas contains a fair amount of carbon dioxide, it is possible to convert
it to syngas by dry reforming also.

Production of biogas can be economically done without much investment and the product gas is
reformed to syngas. However this anaerobic digestion is suitable only for certain specific types
of biomass such as agricultural waste, manure, municipal waste, plant material, sewage, green
waste, food waste, cake after oil extraction etc. Landfill gas is also biogas and easily reformed
to syngas. There are many installations for making methanol/DME in small scale from biogas.
With the recent growth of biodiesel production, large amount of oil cake is available. This
could be easily used in bio-methanation units along with other easily bio digestible materials
to produce biogas.

Methanol and DME Production: Survey and Roadmap | 2017 31