Method for efficient and environmentally clean utilization of solid fuels

摘要

A process of oxidizing an ash and sulfur containing fuel such as coal in order to power gas turbines using a material such as the oxides of iron which in an oxidized state can be readily reduced and which in a reduced state is readily oxidized. Preferably, the oxides of iron are circulated between two fluid bed reactors and reduced by the ash and sulfur containing fuel in the first said fluid bed reactor and oxidized by air in the second said fluid bed reactor, with ash and SO₂ in the gases leaving chiefly from the first said fluid bed reactor. The temperature is controlled within the second said fluid bed reactor by use of a clean fuel and the rate of addition of the ash and sulfur containing fuel to the second fluid bed is controlled so as to limit the amount of SO₂ in the gases leaving the second said fluid bed.