Method of preparing recycled cementitious material by phosphogypsum-assisted carbon sequestration pretreatment process

A method of preparing a recycled cementitious material by a phosphogypsum-assisted carbon sequestration pretreatment process, comprising:

• (1) placing 100 parts by mass of phosphogypsum, 1 to 2 parts by mass of a grinding aid, 10 to 20 parts by mass of a sodium-containing alkali component, 150 to 300 parts by mass of zirconia balls, and 150 to 300 parts by mass of water into a wet grinding tank for wet grinding, before the wet grinding, a pH value of a slurry in the grinding tank being not less than 13, and after 10 min to 30 min of the wet grinding, introducing CO2 at a flow rate of 1.5 to 2.2 parts by mass/min and keeping a temperature of a wet grinding slurry below 40° C., and when the wet grinding slurry reaching a pH value of 10, ending the wet grinding and sieving out the zirconia balls from the wet grinding slurry;
• (2) mixing the wet grinding slurry with 500 to 1000 parts by mass of slag and 100 to 350 parts by mass of water to obtain the recycled cementitious material;
• wherein the sodium-containing alkali component is obtained by mixing one or two of sodium ethoxide and sodium hydroxide with sodium silicate.