60results about How to "Good fluid loss control" patented technology

The invention provides a method of utilizing nanometer silicon dioxide to improve properties of water-based drilling fluid at different temperatures. The method comprises a step of adding a nanometer silicon dioxide dispersing agent into base mud, wherein the mass of the nanometer silicon dioxide particle in the nanometer silicon dioxide dispersing agent is 5-10% of total mass of the base mud and the nanometer silicon dioxide dispersing agent. Due to the nano-scale particle size, the nanometer silicon dioxide material can be filled into small holes and cracks of the shale stratum to improve the plugging effect of the water-based drilling fluid, slow down the trend of permeation of the drilling fluid to the stratum and expansion and chipping of the stratum after water absorption, and improve the stability of the borehole wall. The nanometer silicon dioxide can strengthen the stability of fresh-water base mud and bentonite base mud by increasing the negative charge level of the system. The nanometer silicon dioxide also can enable the base mud to form thinner and compact mud cakes and facilitate the de-filtration effect to be obvious.

The invention relates to an AM (Acrylamide)/DMDAAC (Dimethyl Diallyl Ammonium Chloride)/cyclodextrin polymer filtrate reducer used in petroleum and gas drilling fluid and a preparation method thereof. The invention can solve the technical problems that a well wall is not stable as water loss increases at the pit bottom under the condition of high temperature, and the like. The AM/DMDAAC/cyclodextrin polymer filtrate reducer is characterized by comprising three monomers of AM, DMDAAC and cyclodextrin; the preparation method comprises the following steps of: firstly adding the AM and the DMDAAC into an allyl cyclodextrin water solution according to the mol ratio among the allyl cyclodextrin water solution, the AM and the DMDAAC of 69.2-84.2:30-15:0.8 in sequence; then adding a chelating agent, an oxidant and a reducing agent in sequence; finally evenly mixing, then injecting nitrogen for 20-40min and deoxidizing, and reacting at 30-50 DEG C for 6-8h to obtain the AM/DMDAAC/cyclodextrin polymer filtrate reducer. The preparation method of the polymer is simple, convenient and available and mild in reaction conditions; and the polymer has good filtrate reduction effect in the drilling fluid, is resistant to temperature up to more than 250 DEG C and used in the petroleum and gas drilling fluid.

The invention provides an oil-based drilling fluid filtrate reducer containing a cross-linked structure, and a preparation method. the method is carried out according to the following steps: (1) adding 0.1-30 parts by mass of a long-chain alkyl fatty acid and 1 part by mass of a polyene polyamine into a reaction vessel, stirring uniformly, driving oxygen for 20-30 min with nitrogen, heating to a temperature of 80-160 DEG C and reacting for 15 min-8 h; (2) cooling a temperature of the system to 75-85 DEG C, adding 0.5-25 parts by mass of a humic acid, stirring uniformly, driving the oxygen for 20-30 min with the nitrogen, heating to a temperature of 90-180 DEG C and reacting for 15 min-10 h; (3) adding 0.005-5 parts by mass of a binary or multiple organic acid, stirring uniformly and reacting for 15 min-16 h at a temperature of 100-200 DEG C; and (4) cooling a product obtained by the step (3) to a room temperature, smashing the product, and screening with a 50-100 mesh sieve to obtain the product.

The invention relates to a high-temperature-resistant viscosity-reduction filtrate reducer for a drilling fluid and a preparation method of the filtrate reducer. The filtrate reducer comprises the raw materials of waste acrylon fibers, alkali, mineral acid, hydrogen peroxide, lignite, a sulfonating agent, formaldehyde, copperas and water, wherein the waste acrylon fibers and part of alkali are added in water for reaction at the temperature of 85-95 DEG C; the mineral acid and the hydrogen peroxide are added when the temperature is reduced to 80-85 DEG C, and then the temperature is increased to 85-95 DEG C for reaction for 1-3 h; the remained alkali, lignite, sulfonating agent and formaldehyde are added for reaction for 1-3 hours at the temperature of 85-95 DEG C; the temperature is reduced to 60-80 DEG C, and then ferrous sulfate is added for reaction for 10-30 min; and finally, the product is fetched for drying and smashing. The obtained filtrate reducer not only can reduce the drilling fluid viscosity, but also has a good de-filtration effect and is resistant to high temperature. The filtrate reducer takes the waste acrylon fibers and the lignite as main raw materials, is low in cost and simple in process.

The invention discloses a water-based drilling fluid high-temperature-resistant organic/inorganic hybrid polymer filtrate reducer and a preparation method thereof. The preparation method comprises thefolloiwng steps: uniformly mixing three organic monomers including acrylamide, dimethyl diallyl ammonium chloride and N-vinyl pyrrolidone in proportion, adjusting the pH value to 9, transferring themixture into a three-neck flask, adding inorganic monomer modified nano silicon dioxide while introducing nitrogen, performing ultrasonic dispersion for 25 minutes by an ultrasonic dispersion instrument, transferring the mixture into the three-neck flask, heating to 70 DEG C, adding an initiator, reacting for 7 hours under stirring to obtain milk white viscous liquid, cooling, drying, grinding andcrushing to obtain the organic/inorganic hybrid quaternary graft copolymer. In the invention, the four reaction monomers do not contain sulfonation groups, and the filtrate loss reduction effect of the four reaction monomers at 150-210 DEG C is better than that of a common sulfonation type high-temperature-resistant filtrate loss reducer for an oil field, so that the filtrate loss reducer is environment-friendly and has good filtrate loss reduction property, and the temperature resistance can reach 210 DEG C.

The invention discloses a high-temperature-resistant filtrate reducer for non-sulfonated drilling fluid, and a synthetic method thereof, and belongs to the technical field of oilfield exploitation drilling treatment agents. The preparation method comprises the following steps: dissolving organosilane coupling agent modified nano silicon dioxide in water, and stirring at normal temperature to fullydisperse the modified nano SiO2 to obtain an inorganic modified nano SiO2 suspension; and mixing acrylic acid (AA), dimethyl diallyl ammonium chloride (DMDAAC) and the inorganic modified nano SiO2 suspension in a weight part ratio of (0-20):(0-30):(0-10). According to the invention, a non-sulfonated monomer is preferably selected and inorganic nano SiO2 is added, the advantages and disadvantagesof the organic polymer and the inorganic nanometer are comprehensively considered, and the temperature-resistant filtrate reducer for the non-sulfonated water-based drilling fluid is synthesized, caneffectively reduce the water loss, has good filtrate reduction performance and temperature resistance under the conditions of normal temperature and 180-200 DEG C, and still has certain temperature resistance and salt resistance after being added into saline water-based slurry and saturated saline water-based slurry.

A natural polymer for a filtrate loss reducer for a drilling fluid and a preparation method thereof are disclosed, the natural polymer is prepared from the following raw materials by weight: 5-15 parts of starch, 2-6 parts of AMPS, 10-15 parts of AM, 0.1-1 part of an initiator, 60-80 parts of water and 0.1-1 part of a deoxidizer. The preparation method comprises the following steps: starch hydrolysis, acidification of a starch solution, deoxidization of a starch acid solution and graft copolymerization of the starch acid solution. The performance of the natural polymer is as follows: 4% saline API filtration loss is equal to or less than 8.0mL, after aging at 150 DEG C, the API filtration loss is equal to or less than 14.0mL, saturated brine API filtration loss is equal to or less than 8.0mL, after aging at 150 DEG C, API filtration loss is equal to or less than 13.0mL, compound brine API filter loss is equal to or less than 13.0mL, after aging at 150 DEG C, API filtration loss is equal to or less than 18.0mL. The natural polymer has good performance, can reduce the filtrate loss of the drilling fluid, avoids or reduces the occurrence of complex drilling accidents, improves drilling quality and efficiency, and produces a good environmental protection effect.

The invention relates to a high-temperature resistant viscosity-increasing filtration-loss reducing agent and a preparation method thereof used for a drilling fluid. The viscosity-increasing filtration-loss reducing agent is prepared by adopting the method: adding waste polyacrylonitrile fibre yarns, alkali and ethylene diamine into water, and reacting for 2-9h at a temperature of 90-95 DEG C; cooling down to below 30 DEG C, adding acrylamide, acrylic acid, 2-acrylamido-2-methyl propanesulfonic acid and an initiating agent, heating up to 30-50 DEG C, and continuing reacting for 1-5h; and taking out a product, drying, crushing, and uniformly mixing with auxiliary materials to obtain the high-temperature resistant viscosity-increasing filtration-loss reducing agent. The high-temperature resistant viscosity-increasing filtration-loss reducing agent has the advantages of simple preparation technology, low cost, good viscosity-increasing performance and filtration-loss reducing function, good compatibility with the drilling fluid, no pollution to the environment, and capability of resisting high temperature above 180 DEG C.

The invention provides neopentane beta-cyclodextrin hydroxypropyl tetraether and a preparation method and application thereof. The neopentane beta-cyclodextrin hydroxypropyl tetraether is a tetrapod compound, structurally comprises four beta-cyclodextrin groups, is high in beta-cyclodextrin group cavity proportion, can form a supermolecule clathrate compound with polymer or surfactant in drilling fluid, is high in high temperature resistance, good in salt resistance and stable in rheological property, can have an excellent filter loss lowering effect under the downhole high temperature condition and is promising in application prospect.

The invention discloses a filtrate reducer for drilling fluid and a preparation method thereof. The filtrate reducer comprises sulfonated resin, polymer microcrystals, polyaluminum chloride, carboxymethyl cellulose and calcium carbonate. The sulfonated resin is preferably sulfomethyl phenolic resin, and the polymer microcrystals are preferably modified microcrystalline cellulose. The preparation method comprises the following steps: uniformly mixing polyaluminum chloride, sodium carboxymethyl cellulose and calcium carbonate to obtain mixed powder A, heating the polymer microcrystals to 55-60 DEG C, adding the heated polymer microcrystals and the mixed powder A into sulfonated resin, and uniformly stirring all the materials to obtain the filtrate reducer. The filtrate reducer provided by the invention can effectively solve the problems that the drilling speed is reduced and the environmental pollution is caused by the existing filtrate reducer.

The invention relates to the field of drilling in the petroleum industry, and discloses a star-structure copolymer for reducing filtration loss, a preparation method and application of the copolymer, drilling fluid and application of the drilling fluid. The copolymer contains a structural unit A, a structural unit B, a structural unit C, a structural unit D and a structural unit E, The copolymer is selected from at least one of structural units with structures as shown in a formula (1), a formula (2), a formula (3), a formula (4) and a formula (5), and the number-average molecular weight of the copolymer is 150,000-900,000; When the copolymer is used for a filtrate reducer of the drilling fluid, good high-temperature-resistant and high-calcium-resistant effects and an excellent filtrate reduction effect can be obtained, and the copolymer is suitable for deep well and ultra-deep well operation and can maintain relatively good borehole wall stability.

The invention discloses a cement slurry composition for cementing a well comprising: an hydraulic cement, water and a combination made of a cellulosic polymer and an acrylamido-methyl-propane sulfonate co- or ter-polymer, wherein the density of said cement slurry is above 1700 kg/m³.

The invention discloses a preparation method of a filtrate reducer and the filtrate reducer, and belongs to the technical field of well drilling. The preparation method comprises the following steps: carrying out polymerization reaction on preparation raw materials to obtain the filtrate reducer, wherein the preparation raw materials comprise the following components in parts by weight: 5-20 parts of a first anionic monomer, 15-22 parts of a second anionic monomer, 18-30 parts of a hydrophobic monomer, 4-15 parts of a cationic monomer, 0.6-0.8 part of an initiator, 40-60 parts of water and 12-20 parts of a pH regulator. The first anionic monomer is maleic anhydride and/or acrylic acid; and the second anionic monomer is 2-acrylamide-2-methylpropanesulfonic acid and/or sodium allysulfonate. The prepared filtrate reducer not only can resist temperature and salt, but also is safer and more environment-friendly, and is especially suitable for deep well or ultra-deep well operation.