US 11,725,130 B2
Sodium lignosulfonate as a retarder additive for oil and gas wells cementing
Sara Abdulaziz Alkhalaf, Alkhobar (SA); Abdullah Al-Yami, Dhahran (SA); Vikrant Wagle, Dhahran (SA); and Ali Alsafran, Dhahran (SA)
Assigned to SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed by SAUDI ARABIAN OIL COMPANY, Dhahran (SA)
Filed on Oct. 5, 2021, as Appl. No. 17/494,406.
Prior Publication US 2023/0108150 A1, Apr. 6, 2023
Int. Cl. C09K 8/467 (2006.01); C09K 8/42 (2006.01)
CPC C09K 8/467 (2013.01) [C09K 8/426 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A system, comprising:
a well extending through a downhole formation;
a cement slurry held within a portion of the well, the cement slurry comprising:
a cement in amount of 58% to 79.9% by weight of the cement slurry, wherein the cement comprises 70% to 90% of at least one silicate by weight of the cement;
water in amount of 20% to 40% by weight of the cement slurry; and
an admixture including a retarder in amount of 0.1% to 2% by weight of the cement slurry, wherein the retarder comprises sodium lignosulfonate with an alkali content of no more than 5.0 g Na2O equivalent/liter of the admixture and methanol in an amount of greater than 0 and less than 5 wt % based on weight of the retarder;
wherein the retarder lengthens thickening time of the cement slurry at a temperature range from 100° F. to 195° F.