Research On High Density Cement Slurry System

Shallow oil and gas reservoirs in China have entered the depletion period, thedevelopment of oil and gas in the future will gradually to the deep well, ultra-deep welldirection, since normal density cement slurry system has been unable to meet the needs ofcementing operation, so the research on the high density cement slurry system is particularlyimportant. At present, the density of commonly used high density cement slurry is not morethan2.6g/cm3, and has certain restriction on the use of temperature. In order to effectivelyimprove the performance and the density of cement slurry, this paper has developedexperimental researches on high density cement slurry system.In this paper, we selected out the filtrate reducer SWJ-1, dispersing agent SWJZ-1combined with their properties; Considered the high temperature resistant performance, weused silicon as a suspension stabilizer; Through the indoor experiment, density, we preferablyselected out the high purification iron powder and superfine manganic manganous oxide asthe weighting agent on the evaluation standard of the performance of density、rheology andstrength. Finally, we studied the composite stabilizer of the weighting agent and developed theformulations of the high density cement slurry based on the close packing theory.The density of high density cement slurry systems can be adjusted in the range of2.7~2.8g/cm3,they have with many good advantages such as good rheological、 bettersedimentation stability、 low water loss rate、high compressive strength、superior hightemperature resistance, good channeling ability, suitable thickening time, which can be usedin deep well and ultra deep well cementing.