Topped PFBC combined cycle power plants - 'second generation'

摘要

The coal conversion technology of 2nd-generation pressurized fluidized beds ranks between power plants with complete gasification and those with straight pressurized fluidized bed combustion. The following features are common to all 2nd-generation PFBC variants: · Binding of sulfur with injection of sorbents and its extraction together with the ash · Partial gasification of coal with air · Dry cleaning of the gaseous products generated, fuel gas and flue gas, following only moderate cooling of raw gases · Steam generation from char combustion. The attractiveness of the process lies in the usability of coals of very different grades combined with the conceptual goal of implementing standard gas turbines and operating them at their rated inlet temperatures without the need for extensive engineering expenditures of coal conversion and gas cleaning required for conventional pressurized coal gasification. Several variants have emerged to date, differing primarily in the type and degree of integration of char combustion. Among current commercially-available standard gas turbines, those with external combustion chambers are better suited for such processes than models with can-annular or hybrid burner ring combustors.