Southwest Petroleum University

Baowen Zhang

Zaoyuan Li

Sheng Huang

Yuan Gao

Can Zhou

Donghua Su

Disclosed is a low-molecular-weight composite contamination-resistant additive for well cementing, which includes: 60-85 parts by mass of low-molecular-weight phosphonic acid polymer solution and 15-40 parts by mass of silicate solution. The silicate solution is a low-modulus silicate solution with a mass fraction of 25%-45%, and the low-molecular-weight phosphonic acid polymer solution is a polymer solution with a mass fraction of 35%-60% and prepared from a phosphonic acid group-containing monomer, a rigid group-containing monomer and a carboxylic acid group-containing monomer. The present invention can form stable slurry after being added with drilling fluid, which meets the contamination-resistant requirements under low addition conditions and significantly reduces an amount of spacer fluid used. Compared with the retarder-type contamination-resistant additive that uses the retarding effect to prolong the thickening time, the present invention has a significant effect on abnormal gelation and reducing the consistency of mixed slurry.

Growing community of inventors

Chengdu, China

Baowen Zhang