Process and a plant for the production of Portland cement clinker

摘要

A process is disclosed for producing cement clinker, comprising the steps of: a) providing a mixture of ground calcareous materials and ground argillaceous materials; b) heating the mixture of step a) to a temperature sufficient to calcine and fuse the ground materials to form the cement clinker, and thereby producing an exhaust gas containing CO₂; c) catalysing the hydration of at least a portion of the CO2 contained in the exhaust gas and producing a solution containing bicarbonate ions and hydrogen ions; and d) adding to the solution obtained in step c) metal ions, and adjusting the pH of the solution to precipitate a carbonate or said metal. Preferably, the metal ions are Ca⁺⁺ obtained from the dissolution of a material selected from the group consisting of CaCl₂, cement kiln dust and sea salts and the carbonate is CaCO₃ which is advantageously recycled into the process by adding the CaCO₃ to the mixture of step a). A cement plant for performing this process is also disclosed.