Method to capture CO2 produced by cement plants using the calcium cycle

摘要

A method for capturing CO2 produced by cement plants using the method of calcium cycling, in which the cement is produced by the cement plant by the following method: grinding raw materials comprising limestone, clay and iron ore; homogenize the raw materials in order to produce a raw meal; preheating the raw meal in the preheater section of a cement kiln to produce a flour preheated oil; calcining the preheated raw meal in the calciner section of the cement kiln to produce a calcined raw meal; supplying the raw meal in a rotary kiln calcined in order to produce a clinker; cool the clinker and supplying it to a mill for mixing the clinker with gypsum and cement production, in which the section of the calciner of the cement kiln and rotary kiln produce combustion gases are cooled and have a content of between 30% CO2 and unreacted raw meal containing CaCO3 filtered gas; and wherein the method cycle calcium comprises: contacting said flue gases containing CO2 with a solid stream having a high content of CaO within a first fluidized bed reactor in order to produce a reaction exothermic between CO2 and CaO to produce a solid-gas mixture comprised of a CaCO3 stream and a gas stream having a lower CO2 content; supplying said solid-gas stream to a cyclone to separate the solids from the gas stream and obtain solids and a hot gas CaCO3 having a lower CO2 content; supplying solids CaCO3 to a second fluidized bed reactor to which heat is provided by means of a combustion reaction, in order to decarbonate the CaCO3 and produce a mixture of solid gas comprised of a stream of solid CaO and a stream of gas comprised primarily of CO2 from the hot gas stream leaving the cement plant and the combustion reaction provides heat to the second fluidized bed; supplying the current solid CaO and hot CO2 stream to a second cyclone in order to separate solids from the hot CO2 and produce a stream of CO2 separated from a stream of hot solid CaO; and recycling the CaO to the first fluidized bed reactor, in which the method of the present invention comprises: supplying the combustion gases produced by the section of the calciner and the rotary kiln plant production cement to the first bed reactor fluidized cycle of calcium method; supplying the current solid CaO separated by the second cyclone to the first fluidized bed reactor; purging a quantity of CaO separated by the second cyclone when the ability of CaO to react with CO2 falls, and supply it directly to the rotary kiln cement plant; and provide fresh CaO to the second fluidized bed reactor of cycle calcium method and in the establishment of fresh CaO to the second fluidized bed reactor comprises a mixture obtained by any combination of limestone, raw meal unreacted filtered the flue gases produced by the cement plant (CKD) and cement raw meal taken, for example, directly from a silo of the cement plant.