PRODUCTION OF MANLY CARBONATE BONDED ARTICLE BY CARBONIZATION OF ALKALINE MATERIALS

摘要

A method of producing a mainly carbonate bonded article comprises a step of providing an alkaline granular material comprising one or more alkaline earth metal silicate phases. The method comprises a step of compacting the granular material to obtain a compact of the granular material. The porosity of the compact is smaller than or equal to 37% by volume. The intrinsic permeability of the compact is at least 1·10cm. The method also comprises a reacting step arranged to form at least 5% by weight of carbonates (CO), by reacting the granular material with carbon dioxide in the presence of water, thus transforming the compact into the article. In the reacting step, the compact, being unsaturated with moisture at the beginning of the reacting step, is brought in an atmosphere comprising said carbon dioxide. The atmosphere is at a temperature of at least and at a pressure of at least 0.5 MPa. The pressure is also higher than the saturated vapour pressure of water at said temperature. As a result, at least a portion of said carbonates are formed by reaction of the one or more alkaline earth metal silicate phases. The invention is also related to an article obtained by the method.