The invention relates to the technical field of
cement production, and particularly relates to a preparation process of a polyglycerol
cement grinding aid. The polyglycerol
cement grinding aid is prepared by mixing 90-95% of polyglycerol and 5-10% of inorganic reinforcer. The
polymerization process of the polyglycerol comprises the following steps: adding 15-30% of recovered
glycerol, 1-3% of NaOH and 69-84% of
kerosene into a reactor, heating to 120-180 DEG C under the condition of introducing N2 for protection, and reacting for 4-8 hours while keeping the temperature, wherein the average
polymerization degree n is calculated by determining the
refractive index of the reactant, and the average
polymerization degree n of the polyglycerol is controlled to be 3-5. According to the invention, the prepared
cement grinding aid can change the
dispersity of a material in a mill, effectively eliminate
electrostatic adsorption and mill bonding phenomena of fine cement particles and optimize the
gradation of the cement particles under the condition of not changing the status of the
cement grinding mill. The original yield of the
grinding mill is kept unchanged, the
cement grinding rate and specific area are increased, the 3d strength of the cement is increased by 15%, and the 28d strength is increased by more than 8%. Alternatively, the existing cement grinding rate and specific area are kept, and the yield of the cement
grinding mill can be increased by more than 10%.