Abstract: Disclosed are a method and a system for recycling carbon dioxide. The method includes chlorinating a calcium-containing silicate and/or a magnesium-containing silicate to obtain a calcium chloride and/or magnesium chloride, mixing the calcium chloride and/or magnesium chloride with ammonia water and carbon dioxide and performing a carbonation reaction to recover the carbon dioxide and convert it into calcium carbonate and/or magnesium carbonate while generating an ammonium chloride solution, and recovering the ammonium chloride solution generated in the carbonation reaction. The ammonium chloride solution after being concentrated or hydrogen chloride generated from a decomposition reaction of the ammonium chloride solution is directly used to chlorinate the calcium-containing silicate and/or the magnesium-containing silicate. The ammonium chloride is used as a catalyst for the entire mineralization of the carbon dioxide, the final product is the calcium carbonate and/or the magnesium carbonate.

Abstract: A method of utilizing construction and demolition waste is disclosed. The method comprises pretreating the construction and demolition waste into particles with a predetermined range of size; and obtaining calcium carbonate from the particles. The method of the present invention enables to recycle a wide range of construction and demolition waste, furthermore it can convert these waste materials into the high purity calcium carbonate which can be widely used in many applications.

Abstract: The present invention relates to an apparatus for absorbing and mineralizing carbon dioxide comprising a reactor and a three-phase separator, in which said reactor comprises a tower body and a draft tube disposed inside the tower body, a liquid inlet pipe and a gas intake pipe being disposed on the tower body, the outlet ends of the liquid inlet pipe and the gas intake pipe both being located inside the draft tube; and the three-phase separator is disposed at the upper end of the reactor, and a method therefor.