Study On Membrane Spacer Fluid System

Membrane spacer fluid is a novel technologyof working fluid in oil and gaswells. This technology is from the view of stabilizing borehole andcontrolling formation damage and based on the fundamental principle oftransmitting substance between borehole and formation. At the same time,combined with the ideal of the physical and chemical stabilization borehole,the new system is expected to form the molecular membrane, namelyisolationmembrane,whichcanactasabarrierandpreventspacerfluidanditfiltrate from penetration. furthermore, the barrier has restrained availablyclay hydration, swelling, dispersion and borehole caving, then protectedreservoir.Based on optimizing synthetic methods, the thesis used pre-emulsion andpre-polymerization to synthetise membrane emulsion of spacer fluid, Thesynthetic method could well inhibit organosiloxane to hydrolyze andpolycondensate and get stable polymeric emulsion. In neutral conditions, itgot the best conditions in synthetic reaction. By analysising infraredspectroscopy, it showed that the synthetic polymer contained siloxane andacrylate composition, silicone monomer and acrylate monomer participatedin the copolymerization reaction to guarantee effectively the film properties.Through the single factor and orthogonal experiments, it determined the best formula of the filmogens FA-1 synthesis. Through analysising filtrate cakeandscanningelectronmicroscopeanalysis,itprovedthatthefilmogensFA-1obviouslyhadthefilm-formingproperty.It developed a membrane spacer system which density could regulate itsdensity from 1.10 gram per cubic centimeter to 2.00 gram per cubiccentimeter and had low filtrate and a good ability to control rheologyproperty. The spacer fluid system had well compatibility with drilling fluid,Jiahua G Cement and Shengwei G Cement in rheology, had no flocculation,thickening phenomenon and did not shorten the thickening time, whichwould not affect the cement operation and meet the requirements of cementoperation.