US 11,926,787 B2
Well cementing method for improving well cementing quality by controlling hydration heat of cement slurry
Shuoqiong Liu, Beijing (CN); Hua Zhang, Beijing (CN); Jianzhou Jin, Beijing (CN); Ming Xu, Beijing (CN); Yongjin Yu, Beijing (CN); Fengzhong Qi, Beijing (CN); Congfeng Qu, Beijing (CN); Hong Yue, Beijing (CN); Youcheng Zheng, Beijing (CN); Wei Li, Beijing (CN); Yong Ma, Beijing (CN); Youzhi Zheng, Beijing (CN); Zhao Huang, Beijing (CN); Jinping Yuan, Beijing (CN); Zhiwei Ding, Beijing (CN); Chongfeng Zhou, Beijing (CN); Chi Zhang, Beijing (CN); Zishuai Liu, Beijing (CN); Hongfei Ji, Beijing (CN); Yuchao Guo, Beijing (CN); Xiujian Xia, Beijing (CN); Yong Li, Beijing (CN); Jiyun Shen, Beijing (CN); Huiting Liu, Beijing (CN); Yusi Feng, Beijing (CN); and Bin Lyu, Beijing (CN)
Assigned to PetroChina Company Limited, Beijing (CN); and CNPC Engineering Technology R&D Company Limited, Beijing (CN)
Filed by PetroChina Company Limited, Beijing (CN); and CNPC Engineering Technology R&D Company Limited, Beijing (CN)
Filed on Apr. 21, 2020, as Appl. No. 16/854,376.
Claims priority of application No. 201910547879.4 (CN), filed on Jun. 24, 2019.
Prior Publication US 2020/0399525 A1, Dec. 24, 2020
Int. Cl. E21B 33/14 (2006.01); C09K 8/467 (2006.01)
CPC C09K 8/467 (2013.01) [E21B 33/14 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A well cementing method for improving cementing quality of a well, comprising: controlling the hydration heat of cement slurry to control the degree and rate of hydration heat release from the cement slurry, wherein
the method improves the hydration heat release during formation of cement with curing of cement slurry, improves the binding quality between the cement and the interfaces, and in turn improves the cementing quality at an overlap section of a well;
wherein when the controlling is achieved the cementing quality at the overlap section is improved;
wherein lowering the degree of hydration heat release from cement slurry is achieved by reducing the addition amount of a material generating a high hydration heat;
wherein lowering the rate of hydration heat release from cement slurry is achieved by adding a retarder;
wherein the well cementing is performed on a short-overlap-section well having a length of the overlap section not greater than 150 m; wherein
for well cementing with a separable setting cement slurry comprising a lead slurry and a tail slurry, wherein for the lead slurry, controlling of hydration heat is achieved by lowering the degree and rate of hydration heat release from the slurry, wherein the lead slurry is cement slurry with high strength and low elastic modulus, and its additional safety time for thickening is 60-300 minutes; and wherein for the tail slurry, controlling of hydration heat is achieved by increasing the degree and rate of hydration heat release from the slurry, wherein the tail slurry is cement slurry with high strength, and its additional safety time for thickening is 30-60 minutes;
wherein the high strength occurs when the 7-day strength is greater than 28 MPa, and the low elastic modulus occurs when the elastic modulus is less than 10 GPa.