Abstract: A method for manufacturing supplementary cementitious material and sequestering CO2 by carbonating concrete fines has the following steps: grinding the concrete fines obtained from crushed concrete demolition waste in a mill at a temperature from 1 to 10° C. above the water dew point in a carbonating atmosphere provided by a gas containing from 10 to 99 Vol.-% CO2, circulating the ground and partially carbonated concrete fines in a fluidized bed reactor in contact with the carbonating atmosphere, and withdrawing decarbonated gas and carbonated concrete fines.

Abstract: A method of exhaust gas scrubbing includes providing recycled concrete fines as a waste material rich in carbonatable Ca and/or Mg phases and with d90?1000 ?m and a Rosin-Rammler slope n from 0.6 to 1.4 , injecting the waste material into an exhaust gas stream containing CO2 and/or SOx for reaction with CO2 and/or SOx at a relative humidity of 50 to 100 Vol.-% and a temperature from 40 to 130° C. in an amount of dry waste material ranging from 5 to 30 kg/m3, withdrawing a partly carbonated and/or sulphurized waste material and purified exhaust gas, and recycling a part of the partly carbonated and sulphurized waste material while the remainder is discharged, as well as use of a waste material slurry for exhaust gas cleaning of CO2 and/or SOx.

Abstract: A method for manufacturing supplementary cementitious material and sequestering CO2 by carbonating concrete fines has the following steps: grinding the concrete fines obtained from crushed concrete demolition waste in a mill at a temperature from 1 to 10° C. above the water dew point in a carbonating atmosphere provided by a gas containing from 10 to 99 Vol.-% CO2, circulating the ground and partially carbonated concrete fines in a fluidized bed reactor in contact with the carbonating atmosphere, and withdrawing decarbonated gas and carbonated concrete fines.

Abstract: A method of exhaust gas scrubbing includes providing recycled concrete fines as a waste material rich in carbonatable Ca and/or Mg phases and with d90?1000 ?m and a Rosin-Rammler slope n from 0.6 to 1.4 , injecting the waste material into an exhaust gas stream containing CO2 and/or SOx for reaction with CO2 and/or SOx at a relative humidity of 50 to 100 Vol.-% and a temperature from 40 to 130° C. in an amount of dry waste material ranging from 5 to 30 kg/m3, withdrawing a partly carbonated and/or sulphurized waste material and purified exhaust gas, and recycling a part of the partly carbonated and sulphurized waste material while the remainder is discharged, as well as use of a waste material slurry for exhaust gas cleaning of CO2 and/or SOx.

Abstract: Method for the purification of exhaust gas from the production of cement clinker in a rotary kiln, in which raw materials are ground in a mill to form raw meal, raw meal is preheated in countercurrent in a preheater with exhaust gas from the rotary kiln and optionally precalcined, preheated and optionally precalcined raw meal is supplied to the rotary kiln and burned in the rotary kiln to form cement, the exhaust gas from the rotary kiln is denitrified before entering the preheater of a selective non-catalytic nitrogen oxide reduction with a reagent which provides ammonia, and wherein, according to the invention, the exhaust gas from the preheater is subjected to gas conditioning and catalytic oxidation of ammonia. The object is further solved by means of a device for gas conditioning and catalytic oxidation which is arranged between the preheater and the mill.

Abstract: The apparatus for separating toxic organic substances from a dust-containing exhaust gas of a sintering plant, includes a clay adsorption agent, advantageously consisting of kaolinite, bentonite, illite and/or mixtures thereof, having a mean particle diameter of from 5 to 100 micrometers; a solids-entraining reactor (4) connected to the sintering plant (1) to receive the exhaust gas containing dust from it and a supply device (5) with feed line (6) for supplying the clay adsorption agent to the solids-entraining reactor (4) to bring the entire exhaust gas containing dust into contact with the clay adsorption agent for a reaction time of from 0.5 to 10 seconds above a dew point of the exhaust gas at a temperature from 90.degree. to 180.degree. C. and at a velocity from 6 to 20 meters per second to thus form a gas-solids suspension having a mean suspension density of from 5 to 500 g solids per sm.sup.

Abstract: The process for separating toxic organic substances from a dust-containing exhaust gas from a sintering process, particularly a process of sintering iron ore, includes bringing the entire exhaust gas from a sintering conveyor into contact with clays, layer silicate, and diatomaceous earth or mixtures thereof within a gas-solids suspension for a reaction time of from 0.5 to 10 seconds above the dew point at a temperature from 90.degree. to 180.degree. C. and at a velocity from 6 to 200 meters per second. The median particle diameter, d.sub.50, of the solid adsorption agent in the gas-solids suspension is from 5 to 100 micrometers and the mean suspension density of the gas-solids suspension is from 5 to 500 g solids per sm.sup.3 exhaust gas. The dust and other solids are subsequently jointly separated from the gas-solids suspension, and part of the separated solids is again contacted with the exhaust gas from the sintering conveyor. An apparatus for carrying out the process is also described.