Abstract: A method for operating a plant for producing cement clinker from raw meal having, as viewed in the materials flow direction, at least one calciner for deacidifying the raw meal, and at least one rotary kiln for sintering the deacidified raw meal to form cement clinker. The deacidified raw meal, after passing through the calciner, flows via a cyclone preheating stage into the rotary kiln. Exhaust gases are guided from the rotary kiln into a reactor, arranged between the rotary kiln and the calciner, with fuel being fed into the reactor superstoichiometrically in relation to the dwell time of the exhaust gases in the reactor, so that carbon dioxide in the exhaust gases is reduced to form carbon monoxide. The carbon monoxide is used as a reducing agent for nitrogen oxides, which are chemically reduced in the reactor independently of the short dwell time in the calciner.

Abstract: A method for operating a plant for producing cement clinker from raw meal having, as viewed in the materials flow direction, at least one calciner for deacidifying the raw meal, and at least one rotary kiln for sintering the deacidified raw meal to form cement clinker. The deacidified raw meal, after passing through the calciner, flows via a cyclone preheating stage into the rotary kiln. Exhaust gases are guided from the rotary kiln into a reactor, arranged between the rotary kiln and the calciner, with fuel being fed into the reactor superstoichiometrically in relation to the dwell time of the exhaust gases in the reactor, so that carbon dioxide in the exhaust gases is reduced to form carbon monoxide. The carbon monoxide is used as a reducing agent for nitrogen oxides, which are chemically reduced in the reactor independently of the short dwell time in the calciner.

Abstract: The aim of the invention is to create a bypass system for a cement clinker production line, which is characterized by particularly low investment costs and operating costs, thus being economically favorable. Said aim is achieved by installing the bypass system in such a way that the capacity of pre-existing system filters such as the main exhaust gas filter and/or the cooler exhaust filter can also be used for treating the bypass gas flow.

Abstract: The aim of the invention is to create a bypass system for a cement clinker production line, which is characterized by particularly low investment costs and operating costs, thus being economically favorable. Said aim is achieved by installing the bypass system in such a way that the capacity of pre-existing system filters such as the main exhaust gas filter and/or the cooler exhaust filter can also be used for treating the bypass gas flow.

Abstract: Cement clinker production apparatus having a precalcination stage connected upstream of a rotary kiln, in which precalcination stage a CO-containing reduction zone in the rotary kiln off-gas duct is employed for the purpose of reducing the pollutant NOx. In order to make certain that the quantitative ratio of O2 in the rotary kiln off-gas to fuel admitted by a deNOx burner, and thus control the effectiveness of NOx reduction, a pivoting throttle valve (33) is positioned in the precalcination stage to control the quantity of rotary kiln off-gas and thus the O2 content in the kiln off-gas. The throttle valve (33) is positioned in the rotary kiln off-gas duct (15) above the deNOx burner (19), above the raw meal inlet (13), and before the confluence of the tertiary air substream with the rotary kiln off gas.

Abstract: A system for the manufacture of cement clinker from cement raw meal in which the off-gases of the cement clinker production line not only undergo denitrification but also undergo desulfurization, so that even sulfur-rich raw materials and fuels can be employed without exceeding the prevailing pollutant emission limits. A substream of the oversize material (30) discharged from the mixing chamber (29) of the precalcination stage (16) as solid sorbent may be combined with the off-gas (22) and/or with a partial gas discharge (38) of the rotary kiln off-gas in order to convert the sulfur oxides contained in those off-gases to calcium sulfate (34), which is subsequently separated from the system off-gas.

Abstract: A system for the manufacture of cement clinker from cement raw meal in which the off-gases of the cement clinker production line not only undergo denitrification but also undergo desulfurization, so that even sulfur-rich raw materials and fuels can be employed without exceeding the prevailing pollutant emission limits. A substream of the oversize material (30) discharged from the mixing chamber (29) of the precalcination stage (16) as solid sorbent may be combined with the off-gas (22) and/or with a partial gas discharge (38) of the rotary kiln off-gas in order to convert the sulfur oxides contained in those off-gases to calcium sulfate (34), which is subsequently separated from the system off-gas.

Abstract: Cement clinker production apparatus having a precalcination stage connected upstream of a rotary kiln, in which precalcination stage a CO-containing reduction zone in the rotary kiln off-gas duct is employed for the purpose of reducing the pollutant NOx. In order to make certain that the quantitative ratio of O2 in the rotary kiln off-gas to fuel admitted by a deNOx burner, and thus control the effectiveness of NOx reduction, a pivoting throttle valve (33) is positioned in the precalcination stage to control the quantity of rotary kiln off-gas and thus the O2 content in the kiln off-gas. The throttle valve (33) is positioned in the rotary kiln off-gas duct (15) above the deNOx burner (19), above the raw meal inlet (13), and before the confluence of the tertiary air substream with the rotary kiln off gas.