Abstract: Single phase microemulsions improve the removal of filter cakes formed during drilling with oil-based muds (OBMs). The single phase microemulsion removes oil and solids from the deposited filter cake. Optionally, an acid capable of solubilizing the filter cake bridging particles may also be used with the microemulsion. In one non-limiting embodiment the acid may be a polyamino carboxylic acid. Skin damage removal from internal and external filter cake deposition can be reduced. In another optional embodiment, the single phase microemulsion may contain a filtration control additive for delaying the filter cake removal, destruction or conversion.

Abstract: The invention relates to washpipes for use in drilling operations such as drilling for oil and gas, and more particularly to an auto lubricating washpipe and liner system and method.

Abstract: Methods are given for making scale inhibitors, that were previously incompatible with fluids containing fluoride ion, compatible with fluids containing fluoride ion. Examples of such scale inhibitors include phosphonates and phosphino-polycarboxylates. The method is replacing alkali metal and alkaline earth metal cations, present in salts or bases, or as counter ions of the scale inhibitors, with hydrogen or ammonium ions. Methods of inhibiting scale formation and of dissolving scales are also given.

Abstract: A flow diverter tool assembly is employed for flushing debris from a portion of the bore of a subsea production tree. The flow diverter tool assembly has a housing having a passageway there-through and a seal disposed on an exterior surface of the housing. The seal contacts the inner wall surface of the bore of the production tree, dividing a lower portion of the bore below the seal from an upper portion of the bore above the seal. One or more outlets from the passageway through the exterior surface are disposed along the housing below the seal. A bypass device such as a slip-joint is disposed above the seal to facilitate removal of the flow diverter tool assembly from the bore of the production tree after its use.

Abstract: A method of managing lost returns in a wellbore includes contacting a filter cake with a treating fluid to remove metallic weighting agents from the filter cake, wherein the filter cake is disposed on a face of a formation fracture in the wellbore. The method also includes contacting the filter cake with a proppant slurry, wherein the proppant slurry contacts the filter cake concurrently with the treating fluid or after the treating fluid contacts the filter cake. This method may include increasing the filter cake permeability and may utilize a barite removal agent, such as a chelation agent. At least one related wellbore management method creates a fracture in the wellbore and props open the fracture to increase wellbore integrity to utilize higher weight drilling fluids and prevent fractures from forming further down the wellbore.

Abstract: A method of reducing wax deposition in an oil wellbore tubing includes providing an aqueous bioslurry comprising at least one microbe capable of degrading paraffin wax at about 20-45° C. and a nutrient medium containing one or more carbon source and an oxygen slow-releasing compound. The method further includes providing an oil wellbore completion having a production tubing with an interior surface including a zone that is susceptible to wax deposition when the well is operated to produce oil. The method further includes, while oil production from the well is stopped, incubating the biological slurry in the wax-deposition zone tubing for a sufficient time to multiply the microbe(s) and form a biofilm on at least the wax-susceptible zone.

Abstract: A combination liquid and gas separator and jetting tool includes a housing containing a rotatable drum, a stator in the inlet end of the housing for swirling a liquid/gas mixture, a rotor attached to the drum for rotation by the mixture; whereby the gas and liquid are separated. The liquid and gas are discharged through separate restricted orifices downstream of the drum. Orifices can be located in a rotating head for cleaning, cutting or other downhole operations.

Abstract: The present invention relates to a method of removing deposits from various types of wells (17) including environmental recovery, water supply, horizontal, barrier, injection, recharge, and/or disposal wells (17). The method includes equipping a well (17) with an automated energy delivering system that is attached to the well (17). The energy delivering system is used to clean the surface of the well (17) and aquifer by supplying various types of energy to the well (17) and aquifer via injection lines (5, 6, 11, 12 and 13) and an educator pipe (10). A pump (14) is used to pump the energy through flow valves (20 and 21) and injection lines (5, 6, 11, 12 and 13) and into the well (17). The energy that is supplied to the well (17) mobilizes any deposits in the well (17) and aquifer and cause them to flow into and up the wellbore thereby cleaning the well (17) and aquifer.

Abstract: Water is removed from a natural gas well using a piston pump is driven by a power fluid that is pumped into the wellbore. The power fluid is intermixed within wellbore water and pumped out of the wellbore along with the removed water.

Abstract: A subterranean method of processing a hydrocarbon fluid-containing deposit includes, from a subterranean room, providing a borehole into a deposit containing formation fluid comprising fluid hydrocarbon. The borehole has a first end at a wall of the subterranean room, and a second end remote from the subterranean room and received within the deposit. The first end is elevationally lower than the second end. A string of pipe is provided within the borehole from the subterranean room. A cuttings removal fluid is injected from the string of pipe into the borehole and against a wall of the borehole in underbalanced pressure conditions. One of drilling, reaming, or jetting is conducted within the borehole during said injecting of the cuttings removal fluid. Formation fluid comprising fluid hydrocarbon is flowed from the deposit into the borehole during said injecting of the cuttings removal fluid.

Abstract: Of the many compositions and methods provided herein, one method includes a method comprising: contacting tar resident in a well bore with a treatment fluid comprising a styrene-acrylate polymer; and allowing the styrene-acrylate polymer to interact with the tar to at least partially reduce the tendency of the tar to adhere to a surface. Another method provided herein includes a method for treating tar sand comprising: contacting the tar sand with a treatment fluid comprising an aqueous fluid and a styrene-acrylate polymer, the tar sand comprising tar and sand; and allowing the styrene-acrylate polymers to interact with the tar to at least partially separate the tar from the sand.

Abstract: An assembly for cleanout of scale buildup from a wall of a hydrocarbon well. The assembly is configured to be deployed and operated under pressure without the requirement of coiled tubing to deliver cleanout fluid. The assembly may include a plug for sealing against the wall of the well immediately above the location of scale buildup. A cleanout tool, such as a jetting nozzle may be coupled to the downhole side of the plug. Thus, fluid and pressure may be provided to the well uphole of the plug. In this manner, the plug may direct the fluid to the jetting nozzle to achieve cleanout of the scale buildup.

Abstract: A method for drilling a well with a drilling apparatus comprising a drill string and a bit, comprising attaching a cleaning tool comprising a coaxial pipe and at least one vortex spinner to a portion of the drill string above the bit, inserting the drill string into a wellbore, extending the wellbore while simultaneously pumping fluid through the cleaning tool to create a fluid flow, and loosening debris attached to the wellbore.

Abstract: A method and apparatus for substantially cleaning fill from a borehole is described variously including running a coiled tubing assembly into the wellbore, creating a fluid vortex by circulating cleaning fluid through the coiled tubing, and pulling the coiled tubing and coiled tubing assembly out of the hole at a speed sufficient to substantially clean the particulate solids from the wellbore. An apparatus for substantially cleaning fill from a hole, including vertical, horizontal, or deviated wells also is provided.

Abstract: An equalizing injection wash tool includes a plurality of interconnectable wash tool segments. Each of the segments provides a flow applicator nozzle for transmitting fluid/and or solid from the interior flowbore of the wash tool and into the surrounding formation. Each segment preferably features a plurality of nozzle pipes and nozzles which are oriented about the cross-sectional circumference of the segment in an angularly spaced orientation to provide for a flow pattern that is substantially equalized in an angular manner. In a preferred embodiment, the nozzle pipes have a length that extends into the flowbore of a neighboring wash tool segment.

Abstract: A flushing device (20) comprising an inner sleeve (21), axially slidable relative to an outer sleeve (23). The inner (21) and outer (23) sleeves cooperate to define an inner passage (32) for the flow of a fluid, and are permanently coupled such that there is substantially no rotational movement between the two sleeves. The inner passage (32) has an inlet (22b) and an outlet (22a). The outer sleeve (23) has a plurality of flushing outlets (33) which, when the flushing device (20) is in an open condition allow fluid to be diverted from the inner passage (32). The flushing device (20) also comprises an indexing mechanism (80) which indexes between a first position, wherein the plurality of flushing outlets (33) are blocked from the internal passage (32) such that the flushing device (20) is in a closed condition, to a second position, wherein the plurality of flushing outlets (33) register with the internal passage (32) such that the flushing device (20) is in the open condition.

Abstract: A method for cleaning debris from a wellbore having a top and a bottom comprising inserting cleaning tool comprising a coaxial pipe in the wellbore, pumping fluid through the cleaning tool to create a fluid flow in a direction towards the bottom of the wellbore, converting the fluid flow into rotary mechanical power, agitating the debris by cavitation with at least one vortex spinner having a plurality of spinner blades, and allowing the debris to flow towards the top of the wellbore thereby cleaning the wellbore.

Abstract: A method for removing drilling damage from a formation in a wellbore that has not been produced includes injecting a chemical-acting cleanup fluid and contacting it with a filtercake on a face of a formation of interest for a period of time sufficient to loosen some of the solids embedded in the filtercake. The method further includes circulating a solids removal fluid at a high rate through the wellbore across the face of the formation of interest, the solids removal fluid including a viscosifier, and positioning a second treatment fluid having a fluid loss control pill in the wellbore at the formation of interest. The method further includes degrading particles of the fluid loss control pill and degrading remaining bridging agent from the drilling fluid.

Abstract: A downhole tool which includes a locking bar to allow movement of a sleeve within the tool over a pre-defined range. The range is defined by a recess arranged axially or circumferentially in the tool, in which the bar locates. Fluid can be vented from the recess to provide a hydraulic brake, to prevent premature shearing of any shear pins in the tool. A stabiliser, jetting and circulating tool is described including the locking bar together with applications when incorporated in a bottom hole assembly. The tool allows multiple operations to be performed on a single trip.

Abstract: Corrosive effects arising during oilfield treatment applications are inhibited and/or prevented by introducing into an oil or gas well at least one compound of formula I: wherein: R1 is independently H, —[—CnH2nO—]a—H, or an alkyl group having from 1 to about 24 carbon atoms; R2 is independently H or —[—CnH2nO—]b—H, R3 is independently —[—CH2]c—, or —CdH2d—[—OCnH2n—]e—, R4 is independently H or —[—CnH2nO—]f—H, R5 is independently H or —[—CnH2nO—]g—H, a is from about 1 to about 8; b+f+g is between 0 to about 30; c is from about 1 to 6; d is from about 1 to 6; e is from about 1 to about 8; and n is 2 or 3. Such corrosive effects are especially inhibited in the treatment of sour wells where H2S corrosion is a potential problem as well as conduits used during the treatment of subterranean formations.

Abstract: A scale removal tool with adjustably positionable fluid dispensing arms. The scale removal tool may be configured for delivery to within a hydrocarbon well via coiled tubing. Thus, fluid may be driven through the coiled tubing and through the tool at the fluid dispensing arms. The fluid may thereby be jetted at high pressure toward scale at the wall of the well in order to achieve its removal. In the case of a well having scale of varying thicknesses, the fluid dispensing arms may be dynamically positioned and repositioned while downhole in the well, depending on scale thickness. In this manner, the tool need not be removed from the well in order to reposition the fluid dispensing arms for optimum scale removal at each section of the well. As such, considerable time and expense of a scale removal application may be saved.

Abstract: An aqueous fluid useful for the recovery of crude oil from a subterranean formation, including water and one or more organophosphorus materials and methods for using same.

Abstract: Composites containing a hydrocarbon-soluble well treatment agent may be supplied to a well using a porous particulate. Such well treatment agents may for example inhibit the formation of paraffins, salts, gas hydrates, asphaltenes and/or other deleterious processes such as emulsification (both water-in-oil and oil-in-water). Further, other well treatment agents include foaming agents, oxygen scavengers, biocides and surfactants as well as other agents wherein slow release into the production well is desired.

Abstract: A control line clearing apparatus has a separation sleeve that positions into a downhole element adjacent the element's control port to which a blocked control line connects. The sleeve separates fluid communication from the control port with the annulus between the sleeve and the downhole element, while still allowing effluents in the well tubing to pass through the interior of the sleeve. A feed line is then lowered into the sleeve, and an automatic coupling on the end of the feed line couples to a coupling member inside the sleeve. Once connected, solvent fed through the feed line communicates with the downhole elements control port via a cross-port in the sleeve. In this way, the solvent can act against the other side of the control line blockage.

Abstract: A method and composition and system which for the oxidation, clean up, removal and control of iron and iron deposits in water and the removal of iron deposits and bacterial bio-films from surfaces in water systems. The composition contains sodium chlorite, sodium hypochlorite and citric acid.

Abstract: Disclosed embodiments relate to well treatment fluids and methods that utilize nano-particles. Exemplary nano-particles are selected from the group consisting of particulate nano-silica, nano-alumina, nano-zinc oxide, nano-boron, nano-iron oxide, and combinations thereof. Embodiments also relate to methods of cementing that include the use of nano-particles. An exemplary method of cementing comprises introducing a cement composition into a subterranean formation, wherein the cement composition comprises cement, water and a particulate nano-silica. Embodiments also relate to use of nano-particles in drilling fluids, completion fluids, stimulation fluids, and well clean-up fluids.

Abstract: Disclosed is a method for the treatment of hydrogen sulfide. The method preferably includes forming a solvent-surfactant blend, preparing a microemulsion by combining the solvent-surfactant blend with a carrier fluid and contacting the hydrogen sulfide with the microemulsion. In preferred embodiments, the solvent-surfactant blend includes a surfactant and a solvent selected from the group consisting of terpenes and alkyl or aryl esters of short chain alcohols.

Abstract: A treatment fluid and a method are disclosed for cleaning borehole filtercake using the treatment fluid, wherein the filtercake contains reservoir drilling fluid (RDF) solids. The method includes pumping the treatment fluid downhole in contact with the filtercake to be removed to establish a differential pressure between the treatment fluid and the formation adjacent the filtercake, and evenly propagating treatment of the filtercake during the differential pressure period to delay breakthrough by the treatment fluid for a period from 1 to 12 hours. The treatment fluid comprises a fluoride source providing a 1.2 to 5 molar fluoride concentration, and another acid or combination of acids to provide a pH between 1.8 and 5. The treatment fluid is balanced for a dissolving power high enough to have significant dissolution of the filtercake, but low enough for even propagation to avoid premature leak-off.

Abstract: Fluid producing or injecting wells may be treated with a water-in-oil emulsion for the removal or inhibition of unwanted particulates, including pipe dope, asphaltenes and paraffins. In addition, such emulsions are effective in the displacement of oil base drilling muds and/or residues from such muds from wells. The emulsion may also be used to break the interfacial and/or rheological properties of oil base mud and synthetic oil base mud filter cakes, and act as a demulsifier to break the water-in-oil emulsion present in such oil base and synthetic oil base muds. The water-in-oil emulsions may optionally contain a dispersing agent as well as a surfactant.

Abstract: A composition and method for removing a filter cake from a horizontal wellbore in a subterranean formation using a composition containing a inorganic or organic acidic material, a cationic fluorocarbon surfactant, an alkyl alcohol, water optionally containing ammonium chloride and at least one of an alkyl polyglycoside and a betaine surfactant to produce a stable foam used to remove filter cake from a horizontal wellbore.

Abstract: A composition and method for removing a filter cake from a horizontal wellbore in a subterranean formation using a composition containing a inorganic or organic acidic material, a cationic fluorocarbon surfactant, an alkyl alcohol, water optionally containing ammonium chloride and at least one of an alkyl polyglycoside and a betaine surfactant to produce a stable foam used to remove filter cake from a horizontal wellbore.

Abstract: A swellable polymer gel composition for use in subterranean formations. The composition comprises water, a water soluble polymer, a water soluble crosslinking system and a swelling agent. The crosslinking system may be either a redox system or a chelating system. The amounts of the polymer and the crosslinking system are effective to form a substantially uniformly reacted tri-dimensional gel structure. To the gel solution, is added a swelling agent in an amount sufficient to increase the volume of the gel a predetermined percentage. The swelling agent may be a natural or a synthetic agent. A strengthening agent may be added to increase the gel strength of the composition. The composition has numerous uses and is particularly useful in oil industry applications such as plugging wells, sealing casing leaks and reducing water production from water-bearing hydrocarbon formations.

Abstract: Asphaltene control additives are added to base fluids which are introduced directly or indirectly into a hydrocarbon-bearing formation to mitigate asphaltene deposition in the formation which results in improved permeability in the formation and production of hydrocarbons therefrom. The fluids to which the additive is added may be liquid CO2-based, aqueous-based or non-aqueous-based fluids. Further, the fluids are fracturing fluids, drilling fluids and wellbore treatment fluids such as acidizing fluids.

Abstract: A method of forming an opening for a low temperature well is described. The method includes drilling an opening in a formation. Water is introduced into the opening to displace drilling fluid or indigenous gas in the formation adjacent to a portion of the opening. Water is produced from the opening. A low temperature fluid is applied to the opening.

Abstract: A method for cleaning oil wells to increase the flow of oil thereof by use of a unique aqueous cleaning emulsion comprising of water, hydrocarbon solvent, and detergent. This one step method provides for the simultaneously cleaning/removal of asphaltene and/or paraffin and scale. This method can be used alone or with the assistance of a wash tool which is a combination pressure and surge wash tool having a nipple assembly. A by-pass port is coupled to the nipple assembly and a diverter cup is coupled to the by-pass port. A plurality of pressure wash cups are positioned on the tool. A pressure wash port is located between the plurality of pressure wash cups and a pump shoe assembly is coupled to a bottom pressure wash cup.

Abstract: Many methods are presented including one that comprises: providing a well drill-in and servicing fluid comprising an aqueous fluid, a viscosifier, a fluid loss control additive, a bridging agent, and an orthoester composition; using the well drill-in and servicing fluid to drill a well bore in a subterranean formation; allowing the well drill-in and servicing fluid to establish a filter cake in at least a portion of the well bore; contacting at least a portion of the filter cake with a breaker fluid comprising an orthoester composition; and allowing at least a portion of the filter cake to degrade.

Abstract: A system for cleaning compressors (1) that are situated at a difficultly accessible location, e.g., on or near the seabed or downhole in a well bore, comprises a cleaning liquid line (8) extending between a readily accessible liquid source and the compressor. The liquid source may be a line (7) for supplying hydrate inhibitor, anti foam chemicals, barrier liquid, demulsifier or other types of chemicals to a subsea production or processing activity. Alteratively, the liquid source can be an accumulator tank (13) situated in the vicinity of the compressor.

Abstract: Fluid producing or injecting wells may be treated with a water-in-oil emulsion for the removal or inhibition of unwanted particulates, including pipe dope, asphaltenes and paraffins. In addition, such emulsions are effective in the displacement of oil base drilling muds and/or residues from such muds from wells. The emulsion may also be used to break the interfacial and/or rheological properties of oil base mud and synthetic oil base mud filter cakes, and act as a demulsifier to break the water-in-oil emulsion present in such oil base and synthetic oil base muds. The water-in-oil emulsions may optionally contain a dispersing agent as well as a surfactant.

Abstract: A method of removing metal scale from surfaces that includes contacting the surfaces with a first aqueous solution of a chelating agent, allowing the chelating agent to dissolve the metal scale, acidifying the solution to form a precipitant of the chelating agent and a precipitant of the metal from the metal scale, isolating the precipitant of the chelating agent and the precipitant of the metal from the first solution, selectively dissolving the precipitated chelating agent in a second aqueous solution, and removing the precipitated metal from the second solution is disclosed.

Abstract: A process for inhibiting souring in a hydrocarbon reservoir provides a feed water including a plurality of phosphorous constituents and having an elevated phosphorous concentration. At least some of the phosphorous constituents are removed from the feed water to produce a treated injection water, which has a reduced phosphorous concentration less than the elevated phosphorous concentration. The treated injection water is injected into the reservoir via a first well and the hydrocarbon is produced from the reservoir via a second well. The process inhibits souring in the reservoir insofar as the treated injection water results in a lower level of souring in the reservoir over time than if the feed water had been injected into the reservoir.

Abstract: A downhole impeller device for use within a well, comprising: a body connectable to a drill string and having an external diameter smaller than the well diameter so as to form an annulus between the body and the well; and one or more impeller members extending from the outer surface of the body such that rotation of the or each impeller member impels drilling fluid within the annulus.

Abstract: Fluid producing wells may be treated with a water-in-oil emulsion for the removal or inhibition of unwanted solid particulates, including pipe dope, asphaltenes and paraffins. Such emulsions are of particular applicability in the displacement of oil base drilling muds and/or residues from such muds from producing wells. The water-in-oil emulsions may optionally contain a dispersing agent as well as a surfactant.

Abstract: Treating compositions containing mutual solvents suitable for forming and maintaining single-phase aqueous fluid treating compositions containing very high concentrations of acids and/or chelating agents are described. Methods of use of these treating compositions for dissolving and removing scale and formation matrix material in oil-field treatments such as stimulation and remediation are given.

Abstract: A completion method isolates a lower zone while circulation at high rates takes place above to clean debris out of the wellbore. Pressure fluctuation sensitive equipment in a lower completion is isolated with a tubing valve during circulation. This further prevents debris from clogging inlet pressure passages to equipment below the isolation valve during circulation to get the debris out. After circulation the packer is unset and the tubing valve is opened and a wellbore filter tool directs well fluids through a screen and captures the debris as the string is pulled toward the surface.

Abstract: A method for cleaning a work string which may have been used to inject drilling muds, cement slurries, cement displacement materials and the like into a well where the work strong may contain drilling mud residues, cement slurry residues, cement slurry displacement materials, pipe thread lubricants, pipe dope and the like, as well as corrosion on the inside of the work string by injecting a dispersion slug into and recovering the dispersion slug from the work string.

Abstract: A method and apparatus for substantially cleaning fill from a borehole is described variously including running a coiled tubing assembly into the wellbore, creating a fluid vortex by circulating cleaning fluid through the coiled tubing, and pulling the coiled tubing and coiled tubing assembly out of the hole at a speed sufficient to substantially clean the particulate solids from the wellbore. An apparatus for substantially cleaning fill from a hole, including vertical, horizontal, or deviated wells also is provided.

Abstract: A filter cake deposited by a drilling fluid, drill-in fluid or fluid loss control pill may be removed from a wellbore by introducing into the wellbore a dispersing agent of an organic amino phosphonic acid, ester or salt. The dispersing agent forms a dispersion containing at least a portion of the drilled solids. The dispersing agent may be introduced into the wellbore as a component of a filter cake removal treatment fluid or either prior to or after introduction of the filter cake removal treatment fluid.

Abstract: A formulation containing a copolymer derived from a cationic monomer effectively inhibits and controls the formation of inorganic scales. Suitable copolymers include those comprising an acrylamide unit and a quaternary ammonium salt group, and optionally an acrylate and/or nitrogen heterocyclic monomer including those wherein the quaternary ammonium salt is a unit of the formula: wherein R is methyl or hydrogen; R4 is a C1 to C6 alkyl group, optionally substituted with halogen, hydroxyl and alkoxy groups, X is halogen; and R1, R2 and R3 are independently selected from the group consisting of alkyl and alkoxy groups. Suitable nitrogen heterocyclic compounds include N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, N-vinylcaprolactam, N-vinylimidazole and N-vinylpyridine.

Abstract: A biodegradable water-in-synthetic oil base emulsion, effective in the removal of filter cakes, consists of an external phase of a surfactant emulsified in a paraffinic base oil. The emulsion is particularly effective in breaking-down the interfacial rheological properties of oil base mud and synthetic oil base mud filter cakes and acts as a demulsifier to break the water-in-oil emulsions present in such oil base and synthetic oil base muds.

Abstract: A method of treating a well consists of introducing into the wellbore a biodegradable fluid system containing a fatty acid ester, such as methyl soyate. The fluid system may further contain a lactic acid ester, such as ethyl lactate, and/or a nonionic surfactant. The fluid system may be used in displacement, well remediation and stimulation as well as additional, alternative applications such as the cleaning of surface and/or downhole equipment.