Oilfield profile control agent and preparation method thereof

Abstract

The invention relates to the technical field of oilfield chemistry and oil extraction, and discloses an oilfield profile control agent and a preparation method thereof. The oilfield profile control agent comprises the following components in parts by mass: 28-62 parts of polyester polyol, 4-42 parts of hexamethylene diisocyanate, 2-41 parts of chloroprene rubber, 0.01-3 parts of a catalyst, 2-45 parts of a blocking agent, 1-31 parts of a solvent and 1-20 parts of a plasticizer. A polyurethane prepolymer is prepared by the polymerization of the polyester polyol and the hexamethylene diisocyanate, and then a blocking reaction is carried out on the blocking agent with the polyurethane prepolymer, the solvent, the chloroprene rubber, the plasticizer and the catalyst, so that the oilfield profile control agent provided by the invention is obtained. The product is in a liquid state at normal temperature, can fully enter into the deep micro pores of a stratum, and gels and expands in the stratum; the gelling temperature is controllable, so that the diversion function of the profile control liquid flow of a deep oil reservoir can be realized; the flood conformance volume is increased; thewater flooding effect is improved; and the recovery efficiency is improved.

Description

technical field [0001] The invention relates to the technical fields of oilfield chemistry and oil recovery, in particular to an oilfield profile control agent and a preparation method thereof. Background technique [0002] Most of my country's oilfield production is carried out by water flooding. The water content of the old oilfields in the east exceeds 90%, and the production decline is getting faster and faster. Water plugging and profile control technology has always been an effective means for oilfields to improve water flooding development effects and achieve stable production of oil reservoirs. Swelling particles are a product developed in recent years. Used for profile control of water wells, they can effectively improve water flooding effect, increase water injection swept volume, reduce oil water content, and increase oil recovery. However, when this kind of water plugging and profile control particles are used in deep water displacement, some problems arise, mai...

AI Technical Summary

Problems solved by technology

However, when this kind of water plugging and profile control particles are used in deep water displacement, some problems arise, mainly because the particles absorb water and expand quickly, and they have already begun to expand before they are pumped into the well pipe in the surface liquid distribution tank, so they are not easy to transport to In deeper formations, in addition, due to the low strength of water blocking particles and the expansion in advance, the strength drops significantly, so that during the pumping process, the shearing bulk particles passing through the screen and the formation are easily broken, thus losing the plugging effect. water profile control

[0003] Traditional bulky granule products are generally made of acrylamide, bentonite, additives, etc. under the action of crosslinking agents and initiators, after polymerization, drying, and crushing. It is easy to break due to shearing during transportation. When carrying out deep control and flooding in oil fields, as the transportation distance increases, the profile control effect is greatly affected, and the swept volume of water injection is significantly reduced.