Commercial Processes

The processes listed in Table 9.4 that are reported to be used commercially to supply synthesis gas for methanol production are the Lurgi process, the

Winkler process, the Koppers-Totzek process, and the Texaco process. Down­stream adjustment and treatment of the raw product gases is required when these processes are used to supply feedstock or cofeedstock to a typical low — pressure methanol process operating at 220 to 270°C and 5.066 to 10.132 MPa (50 to 100 atm). A few of the operating details of these and other commercial coal gasification processes are presented here.

Dry Ash Lurgi Process

This process is a fixed-bed process that gasifies crushed, dried coal at 620 to 760°C, 2.43 to 3.14 MPa, and residence times of about 1 h. The raw product gas exits the gasifier at 370 to 590°C and contains tar, oil, naphtha, phenols, ammonia, sulfides, and fines. Quenching with oil removes tar and oil. Catalytic shifting and scrubbing of the quenched product gas provides a gas that can be methanated to produce substitute natural gas, or the equivalent of pipeline gas. The process is limited to noncaking coals.

Добавить комментарий

Ваш e-mail не будет опубликован. Обязательные поля помечены *