摘要:
Water-based fluids that can viscosify under shear or can produce a gel or form a gel under shear are obtained by dissolving polymers in an aqueous phase. These polymers comprise three types of functional groups: non-ionic functional groups that are hydrosoluble at the temperature under consideration, ionic functional groups, and functional groups that are hydrophobic at the temperature under consideration. These three types of functional groups can be distributed or spread in a random distribution along the polymer chain. A slightly block distribution is acceptable. For applications to oil wells, functional groups are used which exhibit LCST (Lower Critical Solution Temperature) behavior (i.e., a low critical solution temperature) instead of hydrophobic functional groups. At temperatures below the LCST, the functional groups are hydrophobic.
摘要:
The present invention concerns a cement slurry with high permeability and good compressive strength, comprising a solid fraction constituted by: 35% to 80% (by volume) of particles with a mean size in the range 100 microns (μ) to 800μ; 0% to 15% (by volume) of particles with a mean particle diameter in the range 0.1 microns to 10 microns; and 10% to 40% (by volume) of particles with a mean particle diameter in the range 20μ to 50μ; a fraction of said-solid particles being constituted by a cement, and preferably a further fraction by self-destructive particles; a liquid fraction in a water/solid ratio in the range 38% to 50% by volume; and a percentage of cells, provided by a gas or a liquid which is not miscible with water, in the range 30% to 60% of the final volume of the slurry.
摘要:
In the presence of certain crude oils, when ferric iron exists in very acidic fluid, it practically instantaneously forms precipitates known as sludges which lead to irreversible damage. Iron control compositions and acid fluids containing such iron control compositions are disclosed. For acid fluids containing up to 15% acid, the iron control composition includes a reducing agent selected from a substituted and unsubstituted thiourea compounds, and a reduction catalyst including a copper (cuprous or cupric) compound. When the acid fluid contains more than 15% acid, for example from 15 to 28% acid, the reducing agent is again selected from substituted or unsubstituted thiourea compounds, and the reduction catalyst is a combination of a copper (cuprous or cupric) compound and iodine (iodine or iodide ions). The invention also includes a process for treatment of oil, water, gas, geothermal or analogous wells using an acid fluid containing an iron control composition according to the present invention, and an industrial cleaning process using a cleaning fluid including an acid fluid containing an iron control agent according to the present invention.
摘要:
The invention relates to the cementing of high temperature wells. The retarder consists of a methylene phosphonic acid derivative and of a boric acid or a borate at least as acid as borax in an aqueous solution, in particular, Na pentaborate, in a preferred ratio of 0.08 to 0.92 parts by weight. A long setting time and a very swift compressive strength development are obtained at the same time.
摘要:
In a fluidized catalytic cracking (FLC) type unit for contacting of a hydrocarbon feedstock with hot solid particles in a fluidized bed in an upright tubular-type upflow hydrocarbon conversion reactor, there is provided, between the means for fluidization and the means for injection of the feedstock, a means for causing the fluidized phase at the periphery of the reactor to rotate about the axis of the reactor.
摘要:
Cementing compositions which are particularly suitable for squeeze cementing operations, comprise an aqueous phase, and a micro-cement, the aqueous phase including an aqueous suspension comprising a vinyl acetate type polymer obtained by chemically cross-linking a polyvinyl compound, a nanolatex and an anionic surfactant with a cloud point of more than 80° C.
摘要:
The present invention relates to copolymers consisting of (a) 1-99% by weight of structural units of the formula (1) where R1 is hydrogen or methyl, R4 is C1-C22-alkylene, R5 is C1-C22-alkyl or hydrogen, and X is ammonium, lithium, sodium, potassium, an amine or a mixture of these substances, and (b) 99-1% by weight of structural units of the formula (2) where R1 is hydrogen or methyl, R2 and R3, independently of one another, are hydrogen, or C2-C22-alkyl, wherein component b) is not hydrolysed and the copolymers have been prepared by a solution precipitation polymerization in a nonaqueous solvent or a water-miscible, organic solvent having a low water content which is a precipitant for the copolymer. The invention furthermore relates to a process for cementing subterranean wells using a cement slurry comprising the following components: a) water of various salinity cement a novel copolymer in a concentration of 0.01-5% bwoc, preferably from 0.05 to 0.9% bwoc.
摘要:
The invention relates to a new, chemically crosslinked PVA. Its application is that of a fluid loss control agent in fluids used in the oil industry, in particular cement slurries, separating fluids, or "spacers", and drilling muds. Its advantages are that it does not delay the setting of the cement, that it has high temperature properties that are relatively insensitive to external conditions.
摘要:
It is proposed a new family of terpolymers based on repeating units of two different types of hydrophobic moieties modified with anionic charged groups. In a preferred embodiment, the first hydrophobic moiety is an aromatic compound such as styrene and the second hydrophobic moiety is a fatty acid. Depending on the modification rate, and on the neutralization degree, the aqueous solutions of the terpolymers have different rheological behavior, ranging from yield point fluid, shear-thickening and polysoaps.
摘要:
Systems for retarding setting in an oilfield well cement slurry comprise a solution of a phosphonate selected from methylene phosphonic acid derivatives and a phosphate, in particular selected from the following salts or the corresponding acids: mono-phosphates (ortho-phosphates PO42; meta-phosphates PO3), acyclic poly-phosphates (pyrophosphates P2O74, tripolyphosphates P3O105) or cyclic poly-phosphates. The system preferably may also comprise a retarder booster and is more particularly applicable to cementing at low or medium temperatures.
摘要翻译:用于在油田井水泥浆中延迟凝固的系统包括选自亚甲基膦酸衍生物和磷酸盐的膦酸盐溶液,特别是选自以下盐或相应的酸:单磷酸盐(正磷酸盐PO42;偏磷酸盐 PO 3),无环多磷酸盐(焦磷酸盐P2O74,三聚磷酸盐P3O105)或环状聚磷酸盐。 该系统优选地还可以包括缓凝剂助剂,并且更特别适用于在低或中等温度下固化。