Shale intercalation inhibitor prepared from hyperbranched quaternary ammonium salt

Abstract

The invention discloses a shale intercalation inhibitor prepared from a hyperbranched quaternary ammonium salt and belongs to the technical field of oil and gas field well drilling. The shale intercalation inhibitor prepared from the hyperbranched quaternary ammonium salt is prepared from the hyperbranched quaternary ammonium salt and water, wherein the mass ratio of the hyperbranched quaternary ammonium salt in the shale intercalation inhibitor is 0.5-4%; the hyperbranched quaternary ammonium salt is synthesized from a polyamine compound and an olefinic bond containing sulfone compound as rawmaterials and one of trimethyl vinyl ammonium, triethyl-vinyl ammonium and trimethyl-1-pentenyl ammonium as an end sealing reagent by the following steps: synthesizing end amino hyperbranched polyamine, and modifying the end amino hyperbranched polyamine. The shale intercalation inhibitor prepared from the hyperbranched quaternary ammonium salt, disclosed by the invention, is safe and nontoxic, and is easily combined with a clay layer with negative electricity, the inhibition performance of the inhibitor is remarkably improved when being compared with that of a similar product, the raw materials are easy to obtain and low in price, and the synthesis method is simple, stable and reliable and applicable to industrial production.

Description

Technical field [0001] The invention relates to a shale intercalation inhibitor for drilling fluids, in particular to a shale intercalation inhibitor made of hyperbranched quaternary ammonium salts, and belongs to the technical field of oil and gas field drilling. Background technique [0002] The stability of the borehole wall has always been a worldwide technical problem that needs to be overcome during the drilling process. According to statistics, 75% of the drilled strata are shale strata, and 90% of borehole wall instability mainly occurs in shale strata, especially water-sensitive strata. The instability of the borehole wall will cause the borehole wall to collapse, reduce diameter, and stuck in the hole, which will increase drilling time and cost. Oil-based drilling fluid has the advantages of good borehole wall stability and strong restraint ability, but it has serious environmental pollution, improper treatment, and high treatment costs. Water-based drilling fluids ha...

AI Technical Summary

Problems solved by technology

[0004] Most of the polyamine inhibitors studied and applied at present have a linear structure. For linear polyamine inhibitors, they usually have an irregular linear configuration after being dissolved in water. When they are used in the shale gas drilling process , the entanglement and coating on the clay are uneven, which is easy to cause repeated adsorption or no adsorption

At the same time, the active groups generally exist at both ends of the molecular chain, so that a molecular chain usually only contains two active groups. In this case, the effect of linear polyamine inhibitors often has certain limitations.

And it is difficult for high molecular weight polyamine compounds to enter the clay layer, so that its inhibitory performance is limited

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