Search results
Results from the WOW.Com Content Network
Underground coal gasification (UCG) is an industrial gasification process, which is carried out in non-mined coal seams. It involves injection of a gaseous oxidizing agent , usually oxygen or air, and bringing the resulting product gas to the surface through production wells drilled from the surface.
Steam and carbon dioxide can also be used as the oxidants. As the metal oxide also serves as the heat transfer medium in the chemical looping process, the exergy efficiency of the reforming and gasification processes like that for the combustion process is also higher as compared to the conventional processes. [1] [2]
The pyrolysis (or devolatilization) process occurs at around 200–300 °C. Volatiles are released and char is produced, resulting in up to 70% weight loss for coal. The process is dependent on the properties of the carbonaceous material and determines the structure and composition of the char, which will then undergo gasification reactions.
[50] [51] Methane pyrolysis is the process operating around 1065 °C for producing hydrogen from natural gas that allows removal of carbon easily (solid carbon is a byproduct of the process). [ 52 ] [ 53 ] The industrial quality solid carbon can then be sold or landfilled and is not released into the atmosphere, avoiding emission of greenhouse ...
An integrated gasification combined cycle (IGCC) is a technology using a high pressure gasifier to turn coal and other carbon based fuels into pressurized gas—synthesis gas . It can then remove impurities from the syngas prior to the electricity generation cycle.
Catalytic fast pyrolysis is a fast process in which the cellulose is broken down to a liquid biofuel. In this approach the cellulose is heated to 500 degrees Celsius in less than one second in a chamber to break apart the molecules. The catalyst forms chemical reactions that remove oxygen bonds and form carbon rings
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. The product gas is brought to the surface through production wells drilled from the surface. [1]
In the Karrick process, 1 short ton of coal yields up to 1 barrel of oils and coal tars (12% by weight), and produces 3,000 cubic feet (85 m 3) of rich coal gas and 1,500 pounds (680 kg) of solid smokeless char or semi-coke (for one metric ton, 0.175 m 3 of oils and coal tars, 95 m 3 of gas, and 750 kg of semi-coke).