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: A method for producing cement clinker in a plant that includes: a first cyclone preheater and a second cyclone preheater for preheating first and second portions of a raw material, respectively; a precalcinator using a combustion gas for burning a fuel, the fumes released by the precalcinator being directed to the second cyclone preheater; a rotary furnace provided with a fuel burner, the fumes released by the rotary furnace being directed to the first cyclone preheater; and a clinker cooler that blows cooling air across the clinker at the outlet of the rotary furnace. According to the method, the precalcinator combustion gas contains between 90 and 100 vol % of oxygen. The precalcinator may consist of a fluidized bed, the fluidization gas being the combustion gas. The invention also relates to a plant as such.

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: A process of manufacturing cement clinker is provided in which a clean supply of CO2 gas may be captured. The process also involves using an open loop conversion of CaO/MgO from a calciner to capture CO2 from combustion flue gases thereby forming CaCO3/CaMg(CO3)2. The CaCO3/CaMg(CO3)2 is then returned to the calciner where CO2 gas is evolved. The evolved CO2 gas, along with other evolved CO2 gases from the calciner are removed from the calciner. The reactants (CaO/MgO) are feed to a high temperature calciner for control of the clinker production composition.

Abstract: A method for capturing CO2 produced by cement plants by using the calcium cycle method comprising the integration of the process known as calcium cycle to the cement plant by using the cement plant raw materials and sub products in the calcium cycle plant and by using the calcium cycle plant raw materials sub products and residual energy in the cement plant

Abstract: A method of manufacturing cement clinker includes a rotary cement kiln having a feed end, a mid-kiln feed location, and a burning end. The rotary kiln is tilted downwardly from the feed end to the burning end so that material introduced into the feed end travels downwardly to the burning end. Heat is directed at the burning end of the rotary kiln. Raw feed material is introduced in the feed end of the rotary kiln. Calcined material having a particle diameter of up to 12 inches is introduced at the mid-kiln feed location. The mid-kiln feed location is arranged in a calcining zone of the rotary kiln.

Abstract: In a method of producing cement clinker and electricity, cement raw mix and hydrocarbon are fed in a circulating fluidized bed boiler (1). Therein cement raw mix is calcined and steam is produced. Gas and solids out of the fluidized bed enter a cyclone (8), the solids being separated therein and returned to the bed. Part of those solids are first cooled down in a solids heat exchanger (9) producing steam. Fly ash consisting predominantly of lime and gas escaping the cyclone are passed through a heat exchanger (28, 33) and a filter (37). Hot bed material is discharged from the circulating fluidized bed and is ground with additives, then blended with lime being separated in the filter (37), then supplied to a rotary kiln (16), wherein the solids are clinkered. The produced steam is fed to a steam turbine island (42).

Abstract: Two-stage classification of a granular material, in particular a cement grinding feed, is accomplished in two classifiers connected in series in such a way that the separative behavior or the separative action and thus the particle-size distribution of the undersized or finished material coming from the second classifier can be modified with simple resources. Part or all of the oversized material of the second classifier is recycled to the second classifier.

Abstract: A process of treating dust from a cement manufacturing operation. The process comprises adding carbon bearing material to the dust catch from a cement manufacturing operation to form a mixture, which is formed into nodules and sizing the nodules to obtain a feed material having a selected size range. The nodules are directed as feed material to a fluidized bed which is maintained by passing air for combustion upwardly through a bed of material. The material is thermal processed within the fluidized bed in a reducing atmosphere by supplying fuel for combustion in the fluidized bed to maintain temperatures sufficient to volatilize alkali and sulfur compounds in the feed material and produce a product having an increased concentration of cement forming compounds and reduced alkali and sulfur compounds as compared to the feed material. The reduced clinker is then re-oxidized to minimize/reverse adverse color and mineralogy.

Abstract: A sintering method of cement clinkers in which preheated cement raw material powder is granulated and sintered in a fluidized bed granulating and sintering furnace, and granulated and sintered clinkers are introduced into a cooling device, for manufacturing high-quality cement clinkers by use of a single fluidized bed-granulating and sintering furnace efficiently with a small heat loss, wherein clinkers are discharged from the fluidized bed granulating and sintering furnace through a clinker dropping hole which is provided in a fluidizing gas distributor of the furnace or in a radial direction extending from the gas distributor, an opening area of the clinker dropping hole is regulated by a gate portion to maintain the differential pressure in a fluidized bed within a predetermined range, air for classifying and cooling the clinkers is blown into a discharge chute connected to the clinker dropping hole, the amount of the blown air is regulated to make the flow velocity of the air blowing from the clinker drop

Abstract: A method of sintering cement clinker is provided including the steps of introducing raw material for cement to a spouted fluidized bed granulating furnace which includes a perforated distributor having a plurality of nozzle holes; passing fluidizing gas through at least one of the plurality of nozzle holes into the spouted fluidized bed granulating furnace while simultaneously blowing classifying gas at a selected flow velocity that is different from the flow velocity of the fluidizing gas into the spouted fluidized bed granulating furnace through a dropping port arranged facing and between the fluidized bed of the spouted fluidized bed granulating furnace and in communication with a fluidized bed sintering furnace; granulating the raw material in the spouted fluidized bed granulating furnace; discharging granules formed in the spouted fluidized bed granulating furnace into the fluidized bed sintering furnace while classifying the granules with the classifying gas; and sintering the granules injected into the

Abstract: With the present invention, a feed preparation system for producing cement includes mixing raw materials with a source of potassium. The mixture is conveyed to feed preparation system where it is placed in condition for treatment in a fluidized bed reactor for thermal processing to produce cement clinker. The potassium combines with the SO.sub.2 generated in the process to form potassium sulfate solids that are filtered from the process gas stream before emission to the atmosphere to thereby reduce sulfur emissions from the fluid bed cement process. The starting material may include white cement raw meal, grey cement raw meal and cement kiln dusts.

Abstract: The invention relates to a method of producing cement clinker from fine-grained cement raw material which after preheating and calcining is burnt in a clinker burning zone divided into two stages and is then cooled. Optimum process conditions, particularly in the clinker burning zone, are achieved in that the calcined material is first of all heated to a temperature up to the region of the sintering temperature in a stage formed by a fluidized bed or spouted bed so that a build-up granulation of the material is brought about, whereupon the material thus heated is heated to the sintering temperature in a second stage of the clinker burning zone which acts as the finish-burning stage and tempered to the finishing burn.

Abstract: A process for producing cement, including preheating a mixture of ground raw materials (raw meal) in a preheating cyclone to form a preheated raw meal, calcining the preheated raw meal in a calciner to form a calcined raw meal, burning the calcined raw meal in a rotary kiln with the aid of a high-grade fuel to form a cement clinker, cooling the cement clinker in a rotary kiln and grinding the cooled cement clinker. The process is characterized by replacing 50 to 70% of the high-grade fuel with a low-grade fuel, gasifying the low-grade fuel in a fluidized bed to form a resulting fuel gas, supplying a first portion of the resulting fuel gas to a main burner of the rotary kiln, a second portion of the resulting fuel gas to the exhaust gas stream from the rotary kiln and a third portion of the resulting fuel gas to the calciner.

Abstract: A suspension shaft furnace and process for producing clinkers from discrete pellets of cement-forming batch materials, the furnace having a top vertical shaft section comprising a pellet-feeding and preheating zone, an intermediate fluidized bed section containing fuel inlet conduits for clinkering of the pellets in a fluidized bed, an air-permeable clinker-impermeable support for supporting the pellets as a fluidized bed, and a lower clinker-cooling section beneath the fluidized bed section. Clinker-discharge means permit the gravity flow of clinkers from the top of the fluidized bed down into a cooling zone in the cooling section. Air inlet means supply a combustion-supporting cooling gas up through the cooling zone, to cool the clinkers therein, and upstream through the fluidized bed section to support the combustion of fuel at the fuel inlet conduits.