Coal Gasification:
-
Process: Coal gasification is a process in which coal is partially oxidised with air, oxygen, steam or carbon dioxide to form a fuel gas.
-
This gas is then used instead of piped natural gas, methane and others for deriving energy.
-
In-situ gasification of coal – or Underground Coal Gasification (UCG) – is the technique of converting coal into gas while it is still in the seam and then extracting it through wells.
-
Production of Syngas: It produces Syngas which is a mixture consisting primarily of methane (CH4), carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2) and water vapour (H2O).
-
Applications:
-
Steel companies typically use coking coal in their manufacturing process. Most of the coking coal is imported and is expensive.
-
To cut costs, plants can use syngas, which comes from coal gasification plants in the place of coking coal.
-
It is primarily used for electricity generation, for the production of chemical feedstocks.
-
The hydrogen obtained from coal gasification can be used for various purposes such as making ammonia, powering a hydrogen economy.
-
Methane or natural gas extracted from coal gasification can be converted into LNG for direct use as fuel in the transport sector.
-
-
Concerns:
-
Coal gasification is one of the more water-intensive forms of energy production.
-
There are concerns about water contamination, land subsidence and disposing of waste water safely.
-
Coal gasification actually produces more carbon dioxide than a conventional coal-powered thermal power plant.
-
The syngas process converts a relatively high-quality energy source (coal) to a lower quality state (gas) and consumes a lot of energy in doing so.
-