Alter NRG’s WPC two-stage plasma process [114] (described in the previ­ous chapter) has been used to build plants of various sizes in the United States, Canada, and Japan. Table 7.12 depicts basic descriptions of some of these plants. This technology provides clean fuel (toxin free) from a vari­ety of mixed feedstock. The basic description of the process is described in Figure 7.4. The plasma technology is most suitable for a mixed feedstock. It uses a moving bed reactor. The temperatures are high enough so that ash is melted and molten ash and slag are collected, vitrified, and discarded into landfill. The composition of the fuel gas produced by this technology depends on the nature of the feedstock, but high temperature and lack of oxygen can lead to the production of clean syngas containing hydrogen and

Plant Locations and Their Capacities for Various WPC Operations

Source: The Alter NRG/Westinghouse Plasma Gasification Process. 2008. Independent Waste Technology report by Juniper Consulting Services Limited, Bathurst House, Bisley UK, November.

carbon monoxide. The product gas composition also depends on the operat­ing conditions. The syngas is purified and conditioned and then converted to numerous different products via FT, methanol, or other syntheses. As shown in Figure 7.4, the process is divided into a number of different steps such that each can be optimized individually or collectively. The feed preparation and handling are a very important part of all new plants. In the second step, the feed can be gasified in one or multiple reactors. Generally one reactor is preferred, because unlike in gasification the slag is not used for further applications.