Abstract: In the method according to the invention for producing cement clinker, raw cement meal is preheated in a preheater, the preheated raw cement meal is precalcined in a calciner and the precalcined raw cement meal is burnt in a kiln, fuel and combustion air having an oxygen content of at least 75 mol % being used in the calciner, and the raw cement meal being precalcined in a fluidized bed in the calciner. The exhaust gases occurring in the kiln are delivered to the preheater, bypassing the calciner, and the exhaust gases of the calciner are delivered to a CO2 preparation device.

Abstract: The method according to the invention for producing cement clinker comprises substantially the following method steps: raw cement material is preheated in a preheater, the preheated material is heated further in a calcining zone while admitting combustion air, and the material heated in this manner is fired in a kiln to form cement clinker, wherein a part of the waste gases developing in the kiln is used to preheat the raw cement material in the preheater, and another part is diverted, and is used in a heat exchanger to preheat the combustion air used in the calcining zone.

Abstract: In the method according to the invention for producing cement clinker, raw cement meal is preheated in a preheater, the preheated raw cement meal is precalcined in a calciner and the precalcined raw cement meal is burnt in a kiln, fuel and combustion air having an oxygen content of at least 75 mol % being used in the calciner, and the raw cement meal being precalcined in a fluidised bed in the calciner. The exhaust gases occurring in the kiln are delivered to the preheater, bypassing the calciner, and the exhaust gases of the calciner are delivered to a CO2 preparation device.

Abstract: In the method according to the invention for producing cement clinker, raw cement meal is preheated in a preheater, the preheated raw cement meal is precalcined in a calciner and the precalcined raw cement meal is burnt in a kiln, fuel and combustion air having an oxygen content of at least 75 mol % being used in the calciner, and the raw cement meal being precalcined in a fluidised bed in the calciner. The exhaust gases occurring in the kiln are delivered to the preheater, bypassing the calciner, and the exhaust gases of the calciner are delivered to a CO2 preparation device.

Abstract: In the method according to the invention for operating a cement plant, the raw meal is preheated in a preheating zone, the preheated material is precalcined in a calcining zone and the precalcined material is finally sintered in a sintering zone. The cement plant is operated in such a manner that the precalcined material which is supplied to the sintering zone has an SO3 concentration of at least 5.5% by mass and a CaSO4 proportion of at least 75%, preferably 90%, of the total salt content.

Abstract: In the method according to the invention for separating mercury from waste gases of a cement production process, the mercury is sorbed on a sorbent, the sorbent is subsequently discharged from the process and supplied to a discharge reactor which is operated with a carrier gas. The sorbent is heated there to temperatures of more than 250° C. so that the mercury is discharged from the sorbent and changed into the gas phase, the gas of the discharge reactor that has accumulated mercury subsequently having the dust removed from it in a preliminary dust removal device, and only a part-flow of the gas which has been enriched and had the dust removed from it in this manner being drawn off at high temperatures and cleaned in a subsequent sorption stage, whilst the remaining part-flow is brought to the temperature required for the discharge of the mercury in the discharge reactor in a heat transfer system and is again supplied as a carrier gas to the discharge reactor.

Abstract: The device according to the invention for carrying out chemical and/or physical reactions between a solid material and a gas, in particular for the preheating, cooling and/or calcining of fine-grain materials, essentially comprises at least one helical and/or spiral conduit, in which the gas-solid material suspension is separated by centrifugal forces into a solid material flow and a gas flow, and, connected to the end of the helical and/or spiral conduit, at least one separation region, to which a solid material conduit for discharging the solid material flow and a gas conduit for discharging the gas flow are connected. The separation region is here formed by a lower part of the gas conduit, the separation region in the region of the junction of the helical and/or spiral conduit and the part of the gas conduit above and adjoining it having the same diameter.

Abstract: The device according to the invention for separating a solid material and a gas substantially comprises an ascending conduit for conducting a gas-solid material suspension having a solid material supply port for feeding in a solid material and a gas supply port for feeding in a gas, a descending helical and/or spiral conduit, in which the gas-solid material suspension is separated into a solid material flow and a gas flow by centrifugal forces, a diverter head that connects the ascending conduit with the helical and/or spiral conduit, wherein in the region of the diverter head at least one bend is provided in the conduit configuration, connected to the end of the helical and/or spiral conduit a solid material conduit for discharging the flow of solid material and also connected to the end of the helical and/or spiral conduit a gas conduit for discharging the flow of gas.

Abstract: A device for performing chemical and/or physical reactions between a solid material and a gas, especially for preheating, cooling and/or calcining fine-grained materials has at least three stages arranged one above the other, each stage comprising the following components: a. a gas-solids suspension duct for conducting a gas-solids suspension, b. means for separating the delivered solid material from the delivered gas, c. a solids duct for discharging the separated solid material, d. and a gas duct for discharging the separated gas, the gas duct of one stage merging into the gas-solids suspension duct of the next-higher stage and the solids duct of one stage joining the gas-solids suspension duct of the next lower stage. In addition, the junction of the solids duct and the gas-solids suspension duct of the third or a higher stage is provided below the highest point of the gas-solids suspension duct arranged two stages lower.

Abstract: The method according to the invention for producing cement clinker comprises substantially the following method steps: raw cement material is preheated in a preheater, the preheated material is heated further in a calcining zone while admitting combustion air, and the material heated in this manner is fired in a kiln to form cement clinker, wherein a part of the waste gases developing in the kiln is used to preheat the raw cement material in the preheater, and another part is diverted, and is used in a heat exchanger to preheat the combustion air used in the calcining zone.

Abstract: The device according to the invention for separating or classifying material to be fed into at least two different grain fractions comprises a screen device, which is formed by rotatable elements, particularly a roller table screen, wherein at least one finer grain fraction passes between the rotatable elements and means are provided for cooling the rotatable elements.

Abstract: In the method according to the invention for separating mercury from waste gases of a cement production process, the mercury is sorbed on a sorbent, the sorbent is subsequently discharged from the process and supplied to a discharge reactor which is operated with a carrier gas. The sorbent is heated there to temperatures of more than 250° C. so that the mercury is discharged from the sorbent and changed into the gas phase, the gas of the discharge reactor that has accumulated mercury subsequently having the dust removed from it in a preliminary dust removal device, and only a part-flow of the gas which has been enriched and had the dust removed from it in this manner being drawn off at high temperatures and cleaned in a subsequent sorption stage, whilst the remaining part-flow is brought to the temperature required for the discharge of the mercury in the discharge reactor in a heat transfer system and is again supplied as a carrier gas to the discharge reactor.

Abstract: The device according to the invention for carrying out chemical and/or physical reactions between a solid material and a gas, in particular for the preheating, cooling and/or calcining of fine-grain materials, essentially comprises at least one helical and/or spiral conduit, in which the gas-solid material suspension is separated by centrifugal forces into a solid material flow and a gas flow, and, connected to the end of the helical and/or spiral conduit, at least one separation region, to which a solid material conduit for discharging the solid material flow and a gas conduit for discharging the gas flow are connected. The separation region is here formed by a lower part of the gas conduit, the separation region in the region of the junction of the helical and/or spiral conduit and the part of the gas conduit above and adjoining it having the same diameter.

Abstract: The device according to the invention for separating a solid material and a gas substantially comprises an ascending conduit for conducting a gas-solid material suspension having a solid material supply port for feeding in a solid material and a gas supply port for feeding in a gas, a descending helical and/or spiral conduit, in which the gas-solid material suspension is separated into a solid material flow and a gas flow by centrifugal forces, a diverter head that connects the ascending conduit with the helical and/or spiral conduit, wherein in the region of the diverter head at least one bend is provided in the conduit configuration, connected to the end of the helical and/or spiral conduit a solid material conduit for discharging the flow of solid material and also connected to the end of the helical and/or spiral conduit a gas conduit for discharging the flow of gas.

Abstract: In the method according to the invention for producing cement clinker, raw cement meal is preheated in a preheater, the preheated raw cement meal is precalcined in a calciner and the precalcined raw cement meal is burnt in a kiln, fuel and combustion air having an oxygen content of at least 75 mol % being used in the calciner, and the raw cement meal being precalcined in a fluidised bed in the calciner. The exhaust gases occurring in the kiln are delivered to the preheater, bypassing the calciner, and the exhaust gases of the calciner are delivered to a CO2 preparation device.

Abstract: The device according to the invention for performing chemical and/or physical reactions between a solid material and a gas, especially for preheating, cooling and/or calcining fine-grained materials has at least three stages arranged one above the other, each stage comprising the following components: a. a gas-solids suspension duct for conducting a gas-solids suspension, b. means for separating the delivered solid material from the delivered gas, c. a solids duct for discharging the separated solid material, d. and a gas duct for discharging the separated gas, the gas duct of one stage merging into the gas-solids suspension duct of the next-higher stage and the solids duct of one stage joining the gas-solids suspension duct of the next-lower stage. In addition, the junction of the solids duct and the gas-solids suspension duct of the third or a higher stage is provided below the highest point of the gas-solids suspension duct arranged two stages lower.

Abstract: In the method according to the invention for operating a cement plant, the raw meal is preheated in a preheating zone, the preheated material is precalcined in a calcining zone and the precalcined material is finally sintered in a sintering zone. The cement plant is operated in such a manner that the precalcined material which is supplied to the sintering zone has an SO3 concentration of at least 5.5% by mass and a CaSO4 proportion of at least 75%, preferably 90%, of the total salt content.

Abstract: The device according to the invention for performing chemical and/or physical reactions between a solid material and a gas, in particular for preheating, cooling and/or calcining fine-grained materials substantially comprises at least one helical and/or spiral line, in which a gas/solid material suspension is separated by centrifugal forces into a solid material flow and a gas flow and at least one separation chamber which is connected to the end of the helical and/or spiral line and which is connected to a gas line in order to direct the gas flow away or which is formed by a portion of the gas line, a solid material line for directing the solid material flow away being connected to the separation chamber. The helical and/or spiral line opens into the separation chamber tangentially at an angle of at least 30° relative to the horizontal and the cross-section of the separation chamber in the region of the opening is from 0.5 to 1.5 times as large as the cross-section of the helical and/or spiral line.

Abstract: The device according to the invention for separating or classifying material to be fed into at least two different grain fractions comprises a screen device, which is formed by rotatable elements, particularly a roller table screen, wherein at least one finer grain fraction passes between the rotatable elements and means are provided for cooling the rotatable elements.

Abstract: A method of desulphurizing flue gases polluted with SO.sub.2 comprising cooling the gases to a temperature of about 0.5 to 20.degree. above the dew point of the gases and flowing the gases through a granular sorbent prepared from a mixture of commercial cement and water.