US 12,486,445 B2
Lightweight composite cement compositions and methods of cementing wells with said compositions
Valerie Gisele Helene Lafitte, Sugar Land, TX (US); Dean Michael Willberg, Houston, TX (US); and Anatoly Medvedev, Cambridge (GB)
Assigned to Schlumberger Technology Corporation, Sugar land, TX (US)
Appl. No. 18/726,493
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
PCT Filed May 22, 2023, PCT No. PCT/US2023/023080
§ 371(c)(1), (2) Date Jul. 3, 2024,
PCT Pub. No. WO2023/225394, PCT Pub. Date Nov. 23, 2023.
Claims priority of provisional application 63/365,097, filed on May 20, 2022.
Prior Publication US 2025/0075115 A1, Mar. 6, 2025
Int. Cl. E21B 33/138 (2006.01); C04B 14/06 (2006.01); C04B 14/28 (2006.01); C04B 16/04 (2006.01); C04B 18/22 (2006.01); C04B 28/08 (2006.01); C09K 8/467 (2006.01); C04B 111/00 (2006.01); C04B 111/40 (2006.01)
CPC C09K 8/467 (2013.01) [C04B 14/06 (2013.01); C04B 14/28 (2013.01); C04B 16/04 (2013.01); C04B 18/22 (2013.01); C04B 28/08 (2013.01); E21B 33/138 (2013.01); C04B 2111/00146 (2013.01); C04B 2111/40 (2013.01); C09K 2208/10 (2013.01)] 18 Claims
 
1. A pumpable composite cement slurry comprising:
cementitious material at a concentration between about 12% by weight and about 34% by weight, calculated to a total weight of the slurry, wherein the cementitious material comprises one or more silica materials that form calcium silicate hydrates upon exposure to water, the one or more silica materials present at a concentration of at least about 12% by weight, calculated to the total weight of the slurry;
inert filler material at a concentration of at least about 30% by weight, calculated to the total weight of the slurry;
nano-sized calcium carbonate particles having a mean particle size of between about 5 nanometers (nm) and about 90 nm, wherein the nano-sized calcium carbonate particles are present at a concentration of between about 0.05% by weight and about 2.5% by weight, calculated to the total weight of the slurry; and
water present at a concentration between about 44% by volume and about 50% by volume, calculated to a total volume of the slurry,
wherein:
the one or more silica materials of the cementitious material have a mean particle size of between about 1 micron and about 20 microns,
the inert filler material has particle sizes of between about 50 microns and about 2 millimeters (mm),
the slurry has a density of between about 9.5 pounds per gallon (ppg) and about 12.5 ppg,
the slurry is curable at a temperature of at least about 100° F. to form a composite cement that has a compressive strength of greater than about 400 pounds per square inch, and
a solid volume fraction of the slurry is greater than about 50%.