GASIFICATION

Gasification is a processes for converting solid or liquid feedstocks into an energy-containing gas (synthesis gas, or syngas) rich in hydrogen (H₂) and carbon monoxide (CO). Other gases such as carbon dioxide (CO₂), methane (CH₄), hydrogen sulfide (H₂S) and various hydrocarbons are also present, and much of the challenge of gasification technology development is conditioning and purifying the syngas to achieve the desired composition. The main gasification reactions are steam reforming (C + H₂O → CO + H₂) and partial oxidation.

Many types of reactors are used for gasification including fixed bed, fluidized bed, and entrained-flow. The choice of reactor depends on the nature of the feedstock, desired conversion and end-use of the syngas. Woody and agricultural residues are typically processed in fluidized bed gasifiers with mechanical belt- and auger-based feed systems, since those can handle that type of low-density, heterogeneous feedstocks. Such gasifiers are fluidized with some combination of steam, oxygen and air and they typically operate at low pressure. For liquid or slurry feedstocks, entrained-flow gasifiers are efficient and can be operated at high pressure with relative ease. Such systems usually involve partial oxidation of the feedstock with pure oxygen using a special type of burner.

At the Advanced Energy Systems Research Facility, we perform gasification testing in the Pressurized Entrained Flow Reactor, Pressurized Fluidized Bed Reactor, Dual Fluidized Bed Reactor or Circulating Fluidized Bed Reactor.