Patent ID: 8601958

Claim:
A process for the combustion of carbon-containing solids with production of carbon dioxide, wherein the carbon conversion is carried out without the aid of a metal, sulphate or sulphide oxygen carrier or a carrier of the M y O x type, with y and x being positive integer with y different from 0 and x which may also be 0 independently from each other, and the process comprises use of an oxidizing fluid bed reactor and a desorption tank operatively interconnected, said process comprising: (a) providing a fuel comprising a fluidized carbon-containing solid; (b) providing an oxidizing fluid bed reactor designed to flow a gas from the bottom to the top of the oxidizing fluid bed reactor, having: (i) a input source for a gaseous flow, wherein the gas comprises an oxygen in the form comprising H 2 O and CO 2 , or H 2 O or CO 2 ; (ii) a fluidized fuel input from the desorption tank or another source, (iii) an output connection to the desorption tank for moving an oxidized fluidized carbon-containing solid; and (iii) an outlet for CO 2 gas and impurities; (c) a desorption tank having: (i) a fluidized fuel input, (ii) an input connection from the oxidizing fluid bed reactor for taking in an oxidized fluidized carbon-containing solid, (iii) an output connection to the oxidizing fluid bed reactor for moving a post-combustion fuel to the oxidizing fluid bed reactor; and (iv) an outlet for CO 2 gas and impurities; (d) oxidating the carbon-containing solid with the gas comprising H 2 O and CO 2 , or H 2 O or CO 2 , wherein the carbon-containing solids are placed in contact with the gaseous flow comprising the oxygen, for a time period and at a temperature sufficient to allow formation of a superficial oxidized complex of carbon-containing solid, wherein the duration of the oxidation is defined according to the expressions: t o >t o.MIN t o <10 [(9500/To)-8] where t o is expressed in s and T o is expressed in K, and temperatures are low enough to avoid carbon consumption and associated release of CO 2 , but sufficient for oxygen to be uptaken by the fluidized carbon-containing solid, after the oxidizing passing the superficial oxidized complex of carbon-containing solid to the desorption tank; and (e) desorpting or combusting the oxidated carbon-containing solid in the absence of O 2 , wherein the superficial oxidized complexes generated by adsorption of the oxygen in step (d) are released in a gaseous form by a decomposition or combustion in the absence of O 2 , wherein the duration of the desorption step (d) is defined according to the expressions: t D <10 [(9500/TD)-8] , with T D expressed in K and t D in s T D <T D.max where t D ranges are in between about 1 and 150 min, T D equal or lower than about 1250K.