Abstract: Disclosed is a process of carrying out a combined gas turbine and steam turbine process of increased efficiency.A fuel gas is produced at a temperature of from 900.degree. to 1100.degree. C. in a circulating fluidized bed by a gasification of 70 to 95 wt. % of the carbon contained in the carbonaceous material and is treated at a temperature of from 850.degree. to 950.degree. C. with suspended solids consisting of calcium hydroxide, calcium oxide and/or calcium carbonate-containing solids to remove pollutants. The main portion of the fuel gas is burnt to produce a gas which is used to operate the gas turbine and which contains at least 5% by volume oxygen and is at a temperature of at least 1000.degree. C. Combustion of the carbonaceous gasification residue to produce process steam is performed in a second circulating fluidized bed at a temperature of from 800.degree. to 950.degree. C.

Abstract: A lime hydrating plant is provided with an external cooler 16 in which the rawer solids portion which is recirculated into a return flow fluidizer 2 (hydrater) is cooled outside the hydrater. This means that less water has to be atomized into the return flow fluidizer 2 than by known plants in order to keep the adequate temperature essential for the hydrating process. Thus dew point decrease may be avoided and a highly reactive hydrated lime may be produced.

Abstract: Disclosed is a process for removing sulfur oxides and optionally other gaseous pollutants from flue gases by means of a reactant which is contained in a circulating fluidized bed and contains sodium, potassium, calcium and/or magnesium as a cation and oxide, hydroxide and/or carbonate as an anion. The adaptation to all operating conditions of the plants by which the flue gas is supplied is simplified in that pollutants are removed from the flue gases when the temperature of the mixture of flue gas and reactant is not in excess of 50.degree. C. above the dew point temperature of water vapor. The reactant is selectively charged at different locations in a dry form, on the one hand, and as an aqueous solution or suspension, on the other hand, the form in which the reactant is charged being controlled in dependence of the temperature and the SO.sub.2 content of the purified gas. If the reactant is charged in a liquid phase it has suitably a solids content of 5 to 30 wt.

Abstract: In a process of removing pollutants consisting substantially of sulfur oxides from exhaust gases at temperatures below 150.degree. C. by means of a sorbent which contains calcium carbonate, calcium oxide and/or calcium hydroxide and which is included in a circulating fluidized bed system consisting of a fluidized bed reactor, a separator and a return line, a complete utilization of the sorbent is achieved in that a partial stream of laden sorbent is withdrawn from the circulating fluidized bed and is subjected at a temperature of 600.degree. to 1200.degree. C. to an oxidizing treatment, a major part of the sorbent that has been subjected to an oxidizing treatment is recycled to the circulating fluidized bed, and a partial stream which contains the sorbent mainly in the form of calcium sulfate is removed from the process. Fresh sorbent is supplied to the circulating fluidized bed and/or to the stage for the oxidizing treatment at the rate at which said partial stream is removed from the process.

Abstract: Hydrogen fluoride is removed from gases by introducing the gases into a fluidized-bed reactor to form a gas-solid suspension, entraining a major part of the solids in an upward direction separating the solids entrained by the gases without prior removal of the solids from the gas-solid suspension, by means of an electrostatic precipitator.