5results about How to "Good filter loss reduction effect" patented technology

This invention discloses a modified bentonite drilling mud, its preparation method, and its application, belonging to the technical field of drilling mud and geotechnical engineering materials. The modified bentonite drilling mud disclosed in this invention, by mass parts, comprises: 100 parts sodium-based bentonite, 0.5 parts anhydrous sodium carbonate, 1-5 parts gum arabic, 0.1-2 parts xanthan gum, and 1000 parts water. The modified bentonite drilling mud disclosed in this invention solves the technical problem that existing drilling muds are unable to simultaneously meet engineering performance requirements, be environmentally friendly, and possess good salt resistance.

This invention discloses an anti-collapse agent for drilling fluids, its preparation method, and its application. The raw materials for the anti-collapse agent include melamine, formaldehyde aqueous solution, organophosphonate, dilute sulfuric acid, water, epichlorohydrin, and a solid acid catalyst. The preparation method of the anti-collapse agent is as follows: 1) Melamine, formaldehyde aqueous solution, and water are mixed evenly, and the pH value of the mixed solution is adjusted to 8-9. Then, the mixture is heated to react and obtain material flow A; 2) Dilute sulfuric acid is introduced into material flow A to react and obtain material flow B; 3) Organophosphonate, solid acid catalyst, and epichlorohydrin are added to material flow B. After the reaction is completed, the mixture is separated and dried to obtain the anti-collapse agent. The anti-collapse agent for drilling fluids provided by this invention has good high-temperature resistance, good salt resistance, temperature resistance, wall solidification, and filtration loss reduction performance. It can meet the requirements of water-based mud anti-collapse and wall solidification in complex well conditions such as deep wells and high-salt brine wells, and extend the safe construction period.

The invention discloses a preparation method of an environment-friendly salt-resistant and high-temperature-resistant filtrate reducer for a long open hole section. The preparation method specifically comprises the following steps: step 1, preparing a first mixed solution; step 2, preparing dispersion liquid; step 3, mixing the first mixed solution and the dispersion solution, and then shearing for 1-2 hours to obtain a shearing solution; step 4, adding the shear fluid into a reaction kettle, introducing nitrogen into the reaction kettle, discharging air in the reaction kettle, keeping the temperature at 70 DEG C, stirring for 10 minutes while keeping the temperature, adding an initiator, and stirring for 10-12 hours to obtain a reaction liquid; step 5, adding the reaction liquid into isopropanol according to a volume ratio of 1: 1.5, stirring for 40 minutes, standing for 2 hours, and filtering to obtain a reaction material; and step 6, washing the reaction material with absolute ethyl alcohol and methanol for 10 minutes respectively, and then drying to obtain the environment-friendly salt-resistant and high-temperature-resistant filtrate reducer for the long open hole section. The problem that an existing filtrate loss agent is poor in filtrate loss reduction performance in a long open hole section is solved.

The invention provides a filtrate reducer and an oil-based drilling fluid as well as a preparation method and application of the filtrate reducer and the oil-based drilling fluid. The preparation method of the filtrate reducer comprises the following steps: mixing acrylonitrile, isobutene and acetone, heating and stirring for a first reaction, and dropwise adding fuming sulfuric acid in the heating and stirring process to obtain a first mixture; mixing N-alkyl acrylamide with the first mixture, and heating for second reaction to obtain a second mixture; dimethylaminoethyl methacrylate and the second mixture are mixed and heated for a third reaction, and a third mixture is obtained; ethyl benzene, carbon tetrachloride and the third mixture are mixed and heated for a fourth reaction, and a fourth mixture is obtained; and extracting and washing the fourth mixture with absolute ethyl alcohol to obtain a white floccule, namely the filtrate reducer. The oil-based drilling fluid comprises an oil phase, bentonite, the filtrate reducer provided by the invention, a flow pattern regulator, a weighting agent and sodium hydroxide. The oil-based drilling fluid provided by the invention has good high-temperature drop filtration performance and is suitable for drilling of deep wells and ultra-deep wells.

This invention relates to a method for preparing and applying a core-shell structured silica plugging agent with a rigid inner structure and a flexible outer structure for marine drilling fluids, belonging to the field of deepwater oil and gas drilling. This invention uses N-vinyl-2-pyrrolidone, dimethyl diallyl ammonium chloride, acrylamide, and 2-acrylamide-2-methylpropanesulfonic acid polymerized and grafted onto the surface of nano-silica to form a core-shell structured silica plugging agent with a rigid inner structure and a flexible outer structure. By utilizing the rigid plugging of nanomaterials and the flexible plugging of polymer deformation, this method effectively seals the micro- and nano-pores of shale and mudstone, thereby maintaining wellbore stability. Simultaneously, it effectively inhibits the secondary formation of hydrates, improving the safety and efficiency of deepwater drilling. Furthermore, the plugging agent of this invention reduces the need for large amounts of thermodynamic inhibitors, saving costs and possessing environmentally friendly properties.