Cementing defoamer is mainly composed of organic hydroxyl compounds, silica, special synergists, and dispersants. It has an obvious effect on removing stubborn fine foam in operation and has a good defoaming, foam inhibition, and degassing effect. The product has good dispersibility, low dosage, and can be well dispersed in the slurry, suppressing the stubborn foam in the mud due to other additives and other reasons. Because of its high temperature and high shear resistance, it will not lose its defoaming performance due to high temperature when drilling. It also has no effect on mud and related additives, which ensures normal production of oil extraction. Cementing is the reinforcement of the good wall, and the reinforcement of the good wall is individual cement and a certain amount of foam will be generated when the cement is mixed with the mixing due to the introduction of air, which is stabilized by the additives in the cement. If these bubbles are not eliminated will affect the strength and quality of the well wall.
Consequences of untreated cementing foam:
While drilling, the mud pump shall be used to pump the mud along the hollow of the drill pipe to the drill bit at the bottom of the drill pipe, and then return to the ground by the gap between the drill pipe and the good wall, and return to carry up the rock chips under drilling, and after the rock chips settle in the mud pool, the clean mud can be recycled again. In drilling, mud not only carries rock chips, cools the drill bit, lubricates the drill pipe, and protects the well wall, but also plays an important role in balancing the formation pressure. When drilling through a formation containing high-pressure oil, gas, and water, if there is no relatively dense mud to hold it down. Oil, gas and water will be automatically ejected.
Effect of adding cementing defoamer:
The defoamer has a certain temperature resistance of 140°C when added to drilling fluids with 0.2% of foaming agent. In the foam drilling fluid, the defoaming rate increased significantly when the addition amount was increased, the rheological parameters and the filtration loss decreased significantly, and the density also increased significantly, and the defoaming effect was good. After several hours of high stirring in the drilling fluid added with the defoamer, the full volume of the drilling fluid became slightly larger as the resting time became longer, and the holding effect of the defoamer was good.
The use of oilfield cementing defoamer will not affect the strength of cementing. cementing defoamer developed for the characteristics of the oilfield industry, specifically to solve the problem of defoaming in oil extraction, fast defoaming speed, long foam inhibition time; good dispersion, can be uniformly dispersed in the original fluid to suppress the generation of foam, no emulsion, no precipitation; in high temperature, high shear, strong acid, strong alkali environment can also be quickly defoamed; adding it will not affect the performance of the original fluid, will not pollute the surrounding environment.