The Noell Process
The Noell process was first developed by Deutsches Brennstoffinstitut Freiberg in 1975 for the gasification of the local browncoal and other solid fuels. It became known under the name GSP. After the Noell Group acquired the technology in 1991 it was further developed to gasify waste materials and liquid residues. This technology is now owned by Future Energy GmbH.
The Noell process features a top fired reactor where the reactants are introduced into the reactor through a single centrally mounted burner [Lorson, Schingnitz and Leipnitz 1995]. This concept has a number of special advantages in addition to those generic
to all dry-feed systems. These include the simple rotational-symmetrical construction without penetrations through the cylinder wall, which reduces equipment costs. Secondly, the use of a single burner reduces the number of flows to be controlled to three (coal, oxygen and steam). Thirdly, slag and hot gas leave the gasification section of the reactor together, which reduces any potential for blockages in the slag tap as well as allowing for both partial and total water quenches, depending on application.
|
Figure 5-18. (b) Noell Gasifier with Cooling Wall (Source: Future Energy GmbH) |
Within this overall concept there are a number of different variations of reactor design for the Noell gasifier, which can be selected and optimised for different feedstocks. Figure 5-18a shows the reactor with a spirally wound cooling screen, typically used for ash-containing conventional fuels (coal, browncoal) and liquids (residual oils, tars, and sludges). The cooling screen is covered with a SiC castible and a layer of molten slag. A partial quench is included in the lower section of the reactor. A reactor with cooling wall is shown in Figure 5-18b, which is used for applications with low or zero-ash feeds such as gas or organic liquid wastes. A third reactor type, which also uses a cooling screen, but has a total quench has been developed for black liquor gasification.