| Microcapsule technology, which relies on the shielding effect of capsule wall, has a good protection effect for the original chemical properties of core materials and has the advantages of improving stability of core materials. This paper mainly studies the applying of microcapsule technology in fracturing gel breaking and plugging control. In fracturing applications we prepared liquid microcapsule breaker which is aimed at clear fracturing fluid by the method of coacervation. It has studied the influence of wall material density, core wall proportion and emulsification conditions on microcapsule products and make system optimization and performance optimization with microcapsule particle size distribution, the rate of retention, release rate, effective content etc as performance parameter by single factor experiment. Studies show that microcapsule gel breaker under the high temperature of 80℃, the release rate was only 15.4% after 5h, has slow release rate. In water plugging control, after injected into the formation, microcapsules slowly release inorganic crosslinker aluminum ion, aluminum ion and HPAM slowly crosslink. In deep formation due to less pressure particles in residence at the larger pores clogged pore throats, which play the role of deep fluid diversion. With super absorbent resin as nucleus and CMC, Part glutaraldehyde crosslinking carboxymethyl cellulose sodium, EC as wall materials making microcapsule, studying the influence of wall material solution density, wall thickness and temperature on release rate of Al3+and respective maximum release rate on condition of lab when microcapsules are made from different wall materials. Meanwhile according to the mechanism of microcapsule with CMC and Glutaraldehyde crosslinking CMC as the wall influencing the release of Al3+, microcapsule release physical model is put forward and its theoretical formula is deduced and established. |
PDF Full Text Request