Coal gasification is the process of converting coal into synthesis gas (also called syngas), which is a mixture of hydrogen (H2), carbon monoxide (CO) and carbon dioxide (CO2).
The syngas can be used in a variety of applications such as in the production of electricity and making chemical products, such as fertilisers.
HOW DOES IT WORK IN HYDROGEN PRODUCTION?
- Chemically, coal is a complex and highly variable substance that can be converted into a variety of products.
- The gasification of coal is one method that can produce power, liquid fuels, chemicals, and hydrogen.
- Specifically, hydrogen is produced by first reacting coal with oxygen and steam under high pressures and temperatures to form synthesis gas, a mixture consisting primarily of carbon monoxide and hydrogen.
- After the impurities are removed from the synthesis gas, the carbon monoxide in the gas mixture is reacted with steam through the water-gas shift reaction to produce additional hydrogen and carbon dioxide.
- Hydrogen is removed by a separation system, and the highly concentrated carbon dioxide stream can subsequently be captured and stored
Benefits of Coal Gasification Technology:
- Promotes alternative usage of domestic coal in eco-friendly manner: This process is around 17 to 20% more efficient than conventional coal-burning to produce electricity
- Hence, it reduces the dependency on coal mining for energy generating power plants.
- Hydrogen Economy: It can be used in hydrogen fuel cell production because gasification of coal is one method that can produce power liquid fuel chemical and hydrogen.
- Reduce Fiscal Deficit: Use of more domestic Coal for energy uses will reduce imports of coal, urea, crude oil and gas, reducing fiscal deficit.
Challenges:
- High Cost: These technologies tend to have high initial cost set up and maintenance cost.
- Not Pollution Free:Develop carbon capture, utilization, and storage technologies that ensure minimal carbon dioxide is released in the production process
- Menace of Coal Mining: It cannot eliminate the environmental harm of coal mining.
- Develop new technologies that can replace the cryogenic process currently used to separate the required oxygen from air.