Gasification

Gasification is a partial oxidation process in which organic material is broken down into a gaseous mixture containing hydrogen (H₂), carbon monoxide (CO), methane (CH₄), and carbon dioxide (CO₂) along with contaminants, such as tars, char an ash. This mix of gases is also known as producer gas or syngas (synthesis gas). Conversion of organic material is achieved by exposing the feedstock to high temperatures, typically 700°C - 1600°C in the presence of a gasifying agent. The gasifying agents used are air, oxygen, steam or a mixture thereof.

Gasification of organic material offers several advantages. The produced syngas can be more efficient than direct combustion of the original feedstock, and can be used for multiple applications, such as heat and electricity generation, including high temperature heat for industry, for mechanical energy, as transport fuel, as raw material for chemicals, and when cleaned and upgraded to near pure methane, can be injected into the grid.

Feedstock

Origin and composition

Usually, gasifiers use wood and other lignocellulosic biomass. It can also be designed to convert the dry organic fraction of municipal solid waste (MSW). Depending on the nature of the organic material, the presence of the moisture content generally varies from 5% to 35%.

Pre-treatment

• Sizing (e.g., chipping, grinding)
• Drying

Process and technologies

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