5results about How to "Easy to flow back" patented technology

The invention provides a low-viscosity temperature-resistant acid solution retarder and a preparation method thereof. The low-viscosity temperature-resistant acid solution retarder disclosed by the invention is a novel retarder which is formed by polymerizing DMC (Dimethyl Carbonate), AM (Acrylamide), DMDAAC (Dimethylaminoethyl Ammonium Chloride), DMAAC-18, perfluorooctyl acrylate and the like. Experiments show that the low-viscosity temperature-resistant acid solution retarder provided by the invention has multiple beneficial effects in the field of petrochemical engineering, on one hand, cationic surfactants such as DMDAAC and DMAAC-18 are added, so that a barrier film can be formed on the surface of rock, and the acid rock reaction rate is reduced; on the other hand, the addition of perfluorooctyl acrylate can reduce the molecular weight of the polymer, so that the pollution to the stratum is reduced.

The present invention provides a quaternary pyridine ammonium salt type perfluoroalkyl ether compound and a preparation method and application thereof. The quaternary pyridine ammonium salt type perfluoroalkyl ether compound has a structural formula of: #imgabs0#. The quaternary pyridine ammonium salt type perfluoroalkyl ether compound of the present invention has multiple functional effects, taking into account the effects of corrosion inhibitor, bactericide and drainage agent for oil fields, and can be used as an oil field auxiliary agent and widely used in related fields, thereby solving the problems of single effect, poor compatibility and complicated liquid preparation of existing oil field auxiliary agents.

The invention discloses a preparation method of a self-diverting acidifier based on a nano process, which comprises the following steps: placing quartz sand in a hydrofluoric acid solution for ultrasonic treatment, then taking out, washing and drying to obtain surface-etched quartz sand; dissolving beta-cyclodextrin in an acid solution, then adding the obtained surface-etched quartz sand and a silane coupling agent, stirring for reaction, standing after the reaction is ended, then centrifuging, washing, drying, grinding and sieving the obtained precipitate to obtain modified quartz sand powder; the preparation method comprises the following steps: sequentially adding a mixed monomer into a polyamino acid solution, simultaneously adding an initiator for reaction to obtain a polymerization reaction product, then adding modified quartz powder, uniformly stirring, and finally washing, drying and crushing an obtained solid product to obtain the self-diverting acidifier. The acidifier obtained according to the invention has obvious self-diverting acidification effect, and can meet the requirements of acidification and acid fracturing of high-temperature deep wells.

The present invention discloses a fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm, comprising a tail seat, a slip group, a slip pusher, a blade support A, a blade support B, a blade, a blade pusher, a release hand, a slip hoop and a center rod. The tail seat is connected to the center rod by threads. The tail seat is connected to an independent five-petal slip through a double-headed threaded sleeve, and is fastened with a slip hoop before setting, and sits on the center rod. The slip pusher, the blade support A and the blade support B are connected to three blades respectively, which are folded and gathered together before setting. Through the downward movement of the blade pusher, the blade support A and the blade support B, each blade is squeezed and opened successively, and cooperates with each other on the same circumferential surface to form a complete arc surface to fit tightly to the casing wall to achieve a sealing effect. The slip pusher continues to descend and squeeze the slip group, so that the slip hoop breaks, and the slip rotates around the double-headed threaded sleeve at one end, so that the slip teeth at the other end quickly bite into the casing wall. The bridge plug of the present invention breaks the sealing mode of conventional bridge plugs and adopts a mechanical seal of a folded blade combination, which has a large diameter change range and can smoothly pass through when the casing of a fracturing operation is severely shrunken and deformed.

This invention provides a small molecule gelling agent and its preparation and application. The method includes: mixing methacryloyloxyethyltrimethylammonium chloride, acrylamide, cationic monomer, and perfluorooctyl acrylate in a certain proportion, diluting with water, adjusting the pH to 5-6, and dissolving to obtain a mixed solution; adding an initiator and an oxidant to the mixed solution, sealing, purging with nitrogen gas, adding a reducing agent, sealing again, heating in a water bath, and stopping the reaction after 4-12 hours to obtain a gel block; chopping the gel block, drying, and grinding it into powder to obtain the small molecule gelling agent. The preparation process of the small molecule gelling agent prepared by this invention is simple, the raw materials are easy to obtain, and all substances in the reaction process are products with no byproducts. The small molecule gelling agent prepared by this invention has good temperature resistance, acid resistance, and corrosion resistance, and its retarding ability meets the requirements of the field. It also has low viscosity, is easy to backflow, and has minimal damage to the formation.