What is the reaction of coal gasification?

Coal gasification is the process of producing syngas—a mixture consisting primarily of carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), natural gas (CH4), and water vapour (H2O)—from coal and water, air and/or oxygen. Historically, coal was gasified to produce coal gas, also known as “town gas”.

What are the reactions involved in gasification?

Within a gasification process, the major chemical reactions are those involving carbon, CO, CO2, hydrogen (H2), water (steam) and methane (CH4), as follows: The combustion reactions: With the above, the combustion reactions are essentially carried out to completion under normal gasification operating conditions.

What is the mechanism of gasification technology?

Fischer-Tropsch Technology Gasification involves the reaction of a source of carbon, possibly associated with hydrogen, with a source of hydrogen (usually steam) and/or oxygen to yield a gas containing hydrogen, carbon monoxide, carbon dioxide and methane.

How does coal gasification work?

Gasification of coal is a process in which coal is partially oxidated by air, oxygen, steam or carbon dioxide under controlled conditions to produce a fuel gas. The hot fuel gas is cooled in heat exchangers, with the production of steam, and cleaned before combustion in a gas turbine.

What are the benefits of coal gasification?

In summary, gasification has inherent advantages over combustion for emissions control. Emission control is simpler in gasification than in combustion because the produced syngas in gasification is at higher temperature and pressure than the exhaust gases produced in combustion.

What is syngas formula?

This can vary significantly depending on the feedstock and the gasification process involved; however typically syngas is 30 to 60% carbon monoxide (CO), 25 to 30% hydrogen (H2), 0 to 5% methane (CH4), 5 to 15% carbon dioxide (CO2), plus a lesser or greater amount of water vapor, smaller amounts of the sulfur compounds …

What is the final product of gasification process?

Then, just as in the gasification process for hydrogen production, a shift reaction step (with steam) converts the carbon monoxide to carbon dioxide. The hydrogen produced is then separated and purified.

What are the disadvantages of gasification?

There is a lack of internal heat exchange in comparison to the updraught gasifier. Less efficiency due to the low heating value of gases. The gasifier can turn inefficient under high uniform temperatures and may become impractical for power ranges above 350 kW.

What are the three main types of gasifiers?

2.3 Types of gasifiers

• 1 Updraught or counter current gasifier. The oldest and simplest type of gasifier is the counter current or updraught gasifier shown schematically in Fig.
• 2 Downdraught or co-current gasifiers.
• Cross-draught gasifier.
• Fluidized bed gasifier.
• 5 Other types of gasifiers.

What are 2 advantages of coal gasification?

Carbon Capture and Storage Separating and capturing carbon dioxide is easier and less expensive when oxygen is used in the gasifier (rather than air), and it does more than lessen the amount of greenhouse gases that are emitted into our atmosphere. Carbon dioxide can actually be useful.

What is syngas used for?

Syngas, a mixture of carbon monoxide and hydrogen, may be used as a clean alternative to fossil fuels in generating electricity or for the production of liquid fuels such as synthetic diesel, dimethyl ether, and methanol (Lv et al., 2007). Syngas production is a two-step process.

What is the chemical equation for the gasification of coal?

Coal gasification reaction (unbalanced): CH 0.8 + O 2 + H 2 O → CO + CO 2 + H 2 + other species 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.

What is underground coal gasification?

Underground coal gasification. Jump to navigation Jump to search. Underground coal gasification ( UCG ) is an industrial process which converts coal into product gas. UCG is an in-situ gasification process, carried out in non-mined coal seams using injection of oxidants and steam.

What is gasification process?

Gasification is a process that converts organic- or fossil fuel-based carbonaceous materials into carbon monoxide, hydrogen and carbon dioxide. This is achieved by reacting the material at high temperatures (>700 °C), without combustion, with a controlled amount of oxygen and/or steam.

What is gasification technology?

Gasification is a technology that converts carbon-containing materials, including coal, waste and biomass, into synthetic gas which in turn can be used to produce electricity and other valuable products, such as chemicals, fuels, and fertilizers.