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

A high-softening point emulsified asphalt water-based drilling fluid additive and a preparation method thereof. The drilling fluid additive comprises 40-70 wt% of asphalt with a softening point of 150 DEG C-240 DEG C, 35-50 wt% of water, 0.02-2 wt% of an auxiliary agent, 0.05-5 wt% of an emulsifier, and 0.01-1 wt% of a stabilizer; the charge of the additive is anion; the storage stability for 1 day is not more than 1%; the storage stability for 5 day is not more than 5%; the high-temperature high-pressure filter loss at 220 DEG C and at 3.45 MPa is not more than 25 ml. The preparation method of the additive comprises the following steps: mixing water, the anion emulsifier, the stabilizer, and the auxiliary agent, then adding the asphalt fine powder with a softening point of 150 DEG C-240 DEG C into the above solution, and stirring. The drilling fluid additive provided by the invention has good high-temperature high-pressure filter loss effect, and is suitable for drilling of high-temperature high-pressure deep wells and extradeep wells.

The present invention relates to drilling fluid compositions and methods of using the same. In various embodiments, the present invention provides a method of treating a subterranean formation including obtaining or providing a drilling fluid composition including a viscosifier including at least one of a poly(vinyl alcohol) copolymer, a crosslinked poly(vinyl alcohol), and a crosslinked poly(vinyl alcohol) copolymer. The method also includes placing the composition in a subterranean formation.

The invention provides a preparation method of an environment-friendly ultrahigh-temperature-resistant filtrate reducer for a water-based drilling fluid, which comprises the following steps: reactingnano hectorite with a silane coupling agent to obtain a nano cross-linking agent; and in the presence of a nano cross-linking agent and an initiator, carrying out polymerization reaction on an amide monomer, a high-temperature-resistant monomer, a cationic monomer and a polyene monomer by using an inverse emulsion polymerization method to obtain the environment-friendly ultrahigh-temperature-resistant filtrate reducer. The filtrate reducer prepared by the preparation method disclosed by the invention can resist high temperature and has an excellent filtrate reduction effect and good environmental protection performance. The filtrate reducer disclosed by the invention is not only suitable for deep and ultra-deep oil and gas drilling, but also suitable for drilling of geothermal wells and environment-sensitive areas.

The invention relates to the field of petroleum exploitation, and discloses a carboxyl-modified graphene graft polymer as well as a preparation method and application thereof. The method comprises: (1) dissolving acrylamide, benzenesulfonic acid, and N-vinylpyrrolidone in water, adding carboxyl-modified graphene, and adding a first emulsifier to obtain an aqueous phase system; adding the second emulsifier Dissolve in the oil phase to obtain an oil phase system; (2) prepare an inverse emulsion system by combining the water phase system with the oil phase system; (3) perform the first polymerization reaction on the inverse emulsion system , to obtain an intermediate product system; the intermediate product system is carried out to a second polymerization reaction to obtain a pre-product; (4) the pre-product is purified, dried and pulverized to obtain a carboxyl-modified graphene graft polymer; wherein , the oxygen element content in the XPS test result of the carboxyl-modified graphene is not less than 26wt%. The polymer provided by the invention is used as a fluid loss reducer for drilling fluid and has excellent temperature and salt resistance.

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.

A high-softening point emulsified asphalt water-based drilling fluid additive and a preparation method thereof. The drilling fluid additive comprises 40-70 wt% of asphalt with a softening point of 150 DEG C-240 DEG C, 35-50 wt% of water, 0.02-2 wt% of an auxiliary agent, 0.05-5 wt% of an emulsifier, and 0.01-1 wt% of a stabilizer; the charge of the additive is anion; the storage stability for 1 day is not more than 1%; the storage stability for 5 day is not more than 5%; the high-temperature high-pressure filter loss at 220 DEG C and at 3.45 MPa is not more than 25 ml. The preparation method of the additive comprises the following steps: mixing water, the anion emulsifier, the stabilizer, and the auxiliary agent, then adding the asphalt fine powder with a softening point of 150 DEG C-240 DEG C into the above solution, and stirring. The drilling fluid additive provided by the invention has good high-temperature high-pressure filter loss effect, and is suitable for drilling of high-temperature high-pressure deep wells and extradeep wells.

It is proposed a new fluid loss control agent useful for the cementation of oil or gas wells. This fluid loss control agent consists of a mixture of a styrene-butadiene latex and a high molecular weight water-soluble polymer such as a copolymer AMPS-Am. The addition of the water-soluble polymer allows drastic reduction of the quantity of latex required to achieve fluid loss control performance and even gas migration control.

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 DMDAACinto 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 discloses a high-temperature resistant and salt-tolerance filtrate reducer for drilling fluid. The method comprises the following steps: copolymerizing three monomers, namely acrylamide, 2-acrylamido-2-methyl-propanesulfonic acid and itaconic acid by using an emulsion polymerization method to obtain a copolymer, and then hydrolyzing under an alkaline condition; and participating and drying to obtain the filtrate reducer. The filtrate reducer has relatively good thermal stability and strong temperature resistance; after 0.5%-1% of high-temperature resistant filtrate reducer is added, the filtrate reducer disclosed by the invention has a good filtration reduction effect in fresh water, saline water, composite saline water and saturated brine drilling liquid. The invention also provides an emulsion polymerization method of the high-temperature resistant and salt-tolerance filtrate reducer for the drilling fluid. In comparison with a conventional polymerization method, the polymerization method disclosed by the invention has the advantages that the polymerization rate and the polymerization degree are obviously improved, the reaction time is obviously reduced, and the production cost is reduced under the premise of good product properties.

The invention relates to an environment-friendly high temperature and salt resistant calcium modified natural polymer fluid loss reducer. Its technical solution is: it is made of the following components, by mass percentage: 20%-30% of modified starch, 3%-8% of partially hydrolyzed polyacrylamide, 3%-5% of aluminum citrate, and 10% of superfine calcium carbonate %‑20%, the balance is water. Beneficial effects are: the present invention is aimed at the downhole complex situation of high-temperature deep well drilling, especially the brine layer, salt rock layer, salt-gypsum layer, and gypsum-mud layer. High temperature and salt-resistant calcium fluid loss reducer is the key to improving the wall-building ability of drilling fluid; the product prepared by the present invention has outstanding fluid loss reducing effect, strong wall-building, temperature resistance up to 150°C and above, salt resistance to saturation, Resistant to 0.5% CaCl 2 . The product has good compatibility with other treatment agents, is non-toxic and environmentally friendly, and can also be used as a protection material for drilling fluid oil and gas layers.