Abstract: The present invention provides methods of decomposing gas hydrates in subsea or subterranean wells, the equipment associated with the wells and in subterranean reservoirs containing gas hydrates. The methods basically comprise the steps of combining an acidic liquid with a basic liquid which chemically react exothermically to form a hot salt solution, contacting the gas hydrates with the hot salt solution to decompose at least a portion of the gas hydrates whereby natural gas and water are released therefrom and recovering the released natural gas, water and salt solution.

Abstract: Discussed is a process for preventing clathrate hydrate masses from detrimentally impeding the possible flow of a fluid susceptible to clathrate hydrate formation. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include polymers having lactam rings. Additives can also contain polyelectrolytes that are believed to improve conformance of polymer additives through steric hinderance and/or charge repulsion. Also, polymers having an amide on which a C.sub.1 -C.sub.4 group is attached to the nitrogen and/or the carbonyl carbon of the amide may be used alone, or in combination with ring-containing polymers for enhanced effectiveness.

Abstract: A method for inhibiting the formation of clathrate hydrates in a fluid having hydrate forming constituents is disclosed. More specifically, the method can be used in treating a petroleum fluid stream such as natural gas conveyed in a pipe to inhibit the formation of a hydrate restriction in the pipe. The hydrate inhibitors used for practicing the method are substantially water soluble polymers formed from a N-substituted acrylamide having two nitrogen substituent groups, R.sub.1 and R.sub.2, where R.sub.1 is a hydrocarbon group having from one to ten carbon atoms and zero to four heteroatoms selected from the group consisting of nitrogen, oxygen, sulfur, and combinations thereof, and R.sub.2 is a hydrogen atom or a hydrocarbon group having from one to ten carbon atoms selected from the group consisting of carbon, nitrogen, oxygen, and sulfur; alternatively, R.sub.1 and R.sub.

Abstract: A method for inhibiting the formation of clathrate hydrates in a fluid having hydrate forming constituents is disclosed. More specifically, the method can be used in treating a petroleum fluid stream such as natural gas conveyed in a pipe to inhibit the formation of a hydrate restriction in the pipe. The hydrate inhibitors used for practicing the method are substantially water soluble polymers formed from a cyclic imino ether. Such polymers may be ring closed cyclic imino ether ("CIE") polymers, ring opened CIE polymers, or combinations thereof. Some examples of ring opened CIE polymers include various N-acyl polyalkyleneimines produced by cationic polymerization, such as N-acyl substituted polyethyleneimine, N-acyl substituted polypropyleneimine, N-acyl substituted polybutyleneimine, N-acyl substituted polypentyleneimine and copolymers thereof.

Abstract: A method and apparatus for achieving in situ bioremediation of volatile contaminants in the vapor phase and dissolved or dispersed contaminants in the groundwater phase at a contaminated site. The apparatus of this invention is configured to be used within a remediation well of the type employed with vapor extraction and dewatering techniques, and serves to biologically treat soil contaminants in situ with microbes and any suitable microbial nutrients. As such, the present invention is adapted to be employed in conjunction with vapor extraction and dewatering remediation techniques to treat vapor and water-borne contaminants more effectively. The apparatus securely retains the microbes in a manner that serves to prevent leaching into the surrounding soil while simultaneously protecting the microbial population from predatory, competitive and inhibitory microorganisms.

Abstract: A method and apparatus for producing a well by varying its downhole pressure. A vacuum is applied to the top of a single string of tubing in a cased wellbore to encourage the formation of free gas at the bottom of the tubing string. The resulting free gas entrains reservoir liquids proximate the inlet opening in the tubing bottom and reduces the pressure gradient in the tubing thus maximizing fluid flow rates to the surface. To further enhance production rates in the event that reservoir gas/oil ratios are too low, supplemental gas volumes may be delivered to the well casing/tubing annulus.

Abstract: A composition for, and an improved process of, enhancing petroleum recovery from a petroleum reservoir by injecting said composition into the reservoir through a wellbore are provided. The aqueous composition is derived from a concentrate which includes a defoaming agent, a demulsifying agent, and optionally a stabilizing agent suitable for stabilizing the concentrate as an aqueous emulsion. In one embodiment, the defoaming agent is dispersed in carrier solvent and the concentrate further includes an emulsifying agent suitable for emulsifying the carrier solvent in water. The composition is preferably injected at a high pumping rate directly into the formation through the tubing-casing annulus and allowed to permeate into the reservoir surrounding the wellbore before oil production commences. The composition and method are particularly suited for used in conjunction with steam injection oil recovery techniques.

Abstract: A method for inhibiting the formation of clathrate hydrates in a fluid having hydrate forming constituents is disclosed. More specifically, the method can be used in treating a petroleum fluid stream such as natural gas conveyed in a pipe to inhibit the formation of a hydrate restriction in the pipe. The hydrate inhibitors used for practicing the method are substantially water soluble polymers formed from a cyclic imino ether. Some examples of such inhibitors include various N-acyl polyalkyleneimines, such as N-acyl substituted polyethyleneimine, N-acyl substituted polypropyleneimine, N-acyl substituted polybutyleneimine, N-acyl substituted polypentyleneimine and copolymers thereof. Also, such N-acyl substituted polyalkyleneimines can be used in various ratios with other substantially water soluble polymers and copolymers. Preferably, a solvent such as water, brine, alcohol, or mixtures thereof is used to produce an inhibitor solution or mixture to facilitate treatment of the petroleum fluid stream.

Abstract: Discussed is a process for preventing clathrate hydrate masses from impeding the flow of fluid in a fluid system. An additive is contacted with clathrate hydrate masses in the system to prevent those clathrate hydrate masses from impeding fluid flow. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member, six member and/or seven member cyclic chemical groupings. Additives include poly(N-vinyl-2-pyrrolidone) and hydroxyethylcellulose, either in combination or alone. Additives can also contain multiple cyclic chemical groupings having different size rings. One such additive is sold under the name Gaffix VC-713.

Abstract: Discussed is a process for preventing clathrate hydrate masses from impeding the flow of fluid in a fluid system. An additive is contacted with clathrate hydrate masses in the system to prevent those clathrate hydrate masses from impeding fluid flow. The process is particularly useful in the natural gas and petroleum production, transportation and processing industry where gas hydrate formation can cause serious problems. Additives preferably contain one or more five member and/or six member cyclic chemical groupings. Additives include poly(N-vinyl-2-pyrrolidone) and hydroxyethylcellulose, either in combination or alone.

Abstract: A method of inhibiting the formation and deposition of scale in the production of hydrocarbons from subterranean reservoirs. The method is particularly effective at inhibiting the formation and deposition of calcium and barium scales in the produced waters of hydrocarbon recovery operations. The method comprises introducing into the produced water a polyepoxysuccinic acid of the general formula: ##STR1## where n ranges from about 2 to about 11, M is hydrogen or a water soluble cation such as Na.sup.+, NH.sub.4.sup.+, K.sup.+ and R is hydrogen, C.sub.1-4 alkyl or C.sub.1-4 substituted alkyl.

Abstract: A method of reducing, preferably preventing, precipitation of asphalt from crude oil. In one aspect, crude oil is contacted in the borehole with at least one N,N-dialkylamide of a fatty acid having 8 to 22 carbon atoms. In an second aspect, precipitation is reduced during miscible flooding in an EOR process by adding to the flooding solvent at least one N,N-dialkylamide of a fatty acid having 8 to 22 carbon atoms.

Abstract: A copolymer of sodium vinyl sulfonate and polyalkylene glycol mono- or di-methacrylate and a process for inhibiting scale deposition, particularly inorganic sulfate such as barium sulfate. An aqueous fluid present in or produced from a subterranean formation is contacted with an aqueous solution having the copolymer dissolved therein. The aqueous fluid has an acidic pH and the copolymer has a molecular weight of from about 2,000 to about 30,000.

Abstract: A method and system, for reducing the temperature of a hydrogeothermal fluid, entails directly or indirectly contacting a self-rising, heated hydrogeothermal fluid with a cooling fluid to cool the hydrogeothermal fluid before it enters and/or as it rises in the production tube.

Abstract: A device for pumping a fluid of high viscosity containing a gas and a liquid phase which includes a pump connected to a lower end of a tubular string at the bottom of a well and a device for separating free gas from the liquid phase and for injecting a thinner into the fluid to reduce the viscosity. Injection of the thinner is effected at fluid inlet ports of an inlet device for separating the free gas via a pipe leading to the surface of a geological formation in which the well is positioned. Also, a pumping method using the device involves injecting the thinner into the fluid of high viscosity near an inlet of the pump.

Abstract: A process is provided for reducing the inhibiting effect of gas coning on liquid hydrocarbon production into a production wellbore penetrating a subterranean formation having a gas cap overlying a liquid hydrocarbon producing zone in fluid communication with the gas cap. A polymer enhanced foam containing a polymer, an aqueous solvent, a surfactant, and a gas is placed in gas-permeable anomalies or matrix between the production wellbore and gas cap, thereby effectively blocking the downward flow of gas from the gas cap to the production wellbore and enabling desirable liquid hydrocarbons to more readily enter the wellbore for production to the surface.

Abstract: Methods are provided for remediating subsurface areas contaminated by toxic organic compounds. An innocuous oil, such as vegetable oil, mineral oil, or other immiscible organic liquid, is introduced into the contaminated area and permitted to move therethrough. The oil concentrates or strips the organic contaminants, such that the concentration of the contaminants is reduced and such contaminants are available to be either pumped out of the subsurface area or metabolized by microorganisms. Microorganisms may be introduced into the contaminated area to effect bioremediation of the contamination. The methods may be adapted to deliver microorganisms, enzymes, nutrients and electron donors to subsurface zones contaminated by nitrate in order to stimulate or enhance denitrification.

Abstract: Biological fouling of water wells is inhibited by replacing the air in the well column with an anoxic gas such as nitrogen to deprive aerobic bacteria of oxygen. The anoxic gas is applied from a cylindrical tank at the surface and through a gas pipe extending from the tank down into the well casing. The well casing is sealed near the top to prevent air infiltration and maintain a positive gas pressure. The anoxic gas is applied at a slightly positive pressure to maintain the well column filled with it and to prevent air penetration. The gas can be supplied to the well column only or to both the well column and the aquifer so that a blanket of gas in the area of the well inhibits air penetration of the water from the unsaturated cover layer above the aquifer.

Abstract: Asphalt precipitation in the flow path of an oil production well is inhibited by splitting the produced crude oil in a separator train into a light fraction containing gaseous and oil components having a relatively low aromaticity and molar weight and a heavy fraction having a relatively high aromaticity and molar weight and subsequently reinjecting at least part of the heavy fraction to a location in the flow path of the well where asphalt precipitation is expected to occur.

Abstract: A method for treating well tubulars and elements (e.g. tubing, casing, sucker rods, etc.) for corrosion, drag reduction, or the like wherein a mass of gelatin is passed downward through the tubular to deposit a protective layer onto the wall of the tubular and/or element. Preferably, the mass of gelatin contains a treating solution therein which forms part of the protective layer. Since such treating solutions can severely damage the production and/or injection formation, the mass is stopped before it completely travels through the tubular and circulation is reversed to return any remaining mass of gelatin and solution back up the tubular towards the surface.

Abstract: A method of removing iron from ground water located in a water well and of preventing production of hydrogen sulphide in such water including positioning a bubbling device in the well below the waterline. This device, which is connected to a source of pressurized air, is operated to produce a continuous flow of air bubbles in the water to render dissolved iron in the water insoluble so that the latter precipitates out and the well water aerobic. The insoluble iron can then be gathered from the well periodically. In one version, an iron collecting device in the form of a bag is placed around the bubbling device. The bag is removable from the well in order to remove and dispose of collected insoluble iron. Calcium carbonate can be used to adjust the pH level to pH 7. When the bubbling device is introduced into water containing sulphur, the air stream of bubbles has a double action and prevents hydrogen sulphide production.

Abstract: Gas hydrate formation in a gas well is prevented by injecting a carrier and an alcohol (e.g., glycerol or a glycerol derivative) into the well and connected facilities/pipelines.

Abstract: This invention relates to a method for stabilizing and maintaining water wells penetrating a subterranean formation for the production of water which comprises adding to the wells at least one anionic polymeric sequesterant derived from a carboxylic acid and then subsequently treating the well water with a small but effective amount of at least one biocide.

Abstract: A geothermal water well is treated with an effective amount of a scale inhibitor formulation containing a Na acrylate/acrylamide copolymer to inhibit the buildings of CaCO.sub.3 scale therein.

Abstract: A method of inhibiting corrosion in an oil well comprises introducing into the well a pourable emulsion comprisinga. 50-95% of a discontinuous aqueous phase (such as ordinary water); andb. 5-50% of a continuous oil phase (such as kerosene or similar hydrocarbon) containing a corrosion inhibiting compound (such as an imidazoline).This method results in more consistent corrosion protection, even if longer treatment intervals are used.

Abstract: A method and apparatus are provided for locating a solvent injection apparatus within a natural gas wellbore to reduce the deposition of hydrocarbonaceous solids which are at least partially soluble in the solvent.

Abstract: A process for recovering oil from a subterranean hydrocarbon-bearing reservoir having a hydrocarbon and penetrated by a wellbore. The process comprises injecting through the wellbore and into the subterranean hydrocarbon-bearing reservoir an emulsifying composition containing an aqueous phase and a minor amount of an emulsifying agent such that the emulsifying composition contacts at least a portion of the hydrocarbon to form an oil-in-aqueous phase emulsion within the subterranean hydrocarbon-bearing reservoir.

Abstract: Corrosion inhibition composition formed as a water-external emulsions having an oil soluble organic film forming type of corrosion inhibitor in the dispersed phase thereof are disclosed for downhole well applications, such emulsions having a stability at room temperature without agitation of from 2 to 30 minutes.

Abstract: The present invention relates to a method of preventing potential subterranean formation damage caused by calcium based completion and well servicing brines.

Abstract: A method is provided for transporting in a duct a fluid comprising gas and water, and being under conditions where at least one hydrate is formed, the hydrates being formed from said gas and said water, wherein, before or during the formation of the hydrate or hydrates, an additive is injected into said fluid for reducing the tendency to agglomeration of the hydrate so as to obtain one or more hydrates in dispersed form, and said fluid is transported containing said hydrate or hydrates in dispersed form.

Abstract: A remedial treatment for coal degas wells is described which enhances the production flow of gas and/or water from the wells. The treatment comprises the steps of: (a) injecting an aqueous foam through the wellbore and into the coal seam(s) at a pump rate of about 10 to about 40 BPM; and (b) flowing back the well at the maximum rate through an open, unrestricted choke.

Abstract: A method for inhibiting the deposition of wax in an oil well producing a wax-containing petroleum from a subterranean formation comprises injecting into the oil pool at the base of said well a copolymer comprised of ethylene and vinyl acetate and having an average molecular weight between about 15,000 and about 35,000.

Abstract: A downhole pump is actuated by a reciprocating unit comprising a tubular rod string, a valve assembly, and a tubular plunger rod. A flow passage extends through the reciprocating unit when the valve assembly is in an "open" position, whereby liquid may be injected into the pump barrel chamber to ensure the presence of incompressible fluid in the chamber from the beginning of the up stroke, to thereby reduce or eliminate gas locking of the pump. The valve assembly, which moves together with the reciprocating unit of which it is part, is adapted to interact with a stop member on the stationary pump barrel, to initiate opening of the valve as the rod string approaches the bottom of its stroke. The valve assembly is further adapted to automatically close when lifted away from the stop shortly after the beginning of the up stroke. The valve thus remains open only during the bottoming out phase of the stroke, when only limited travel of the reciprocating unit occurs.

Abstract: Stoppage of gas-water streams due to the formation of gas hydrates is prevented by incorporating in such streams a surface active agent which inhibits the formation of gas hydrates and/or the agglomeration of hydrate crystallites into large crystalline masses.

Abstract: Treatment fluid is injected into the production fluid of a well from a bladder contained in a canister at the bottom portion of the well bore. The flow rate is predetermined through use of a capillary tube connecting the bladder and an injection outlet. Differential pressure between the bladder and the outlet to actuate the flow of treatment fluid is created either by restricting the flow of production fluid adjacent the outlet or by compressing the bladder through the use of water-expansible material in contact with the bladder in the canister. An aperture in the bottom of the canister is provided to expose the bladder to the well fluid.

Abstract: A process for the preparation of a natural liquid fuel and, more particularly, a process that allows a high sulfur natural fuel to be converted into energy by combustion with a substantial reduction in sulfur oxide emissions.

Abstract: A composition is provided which, when applied to a metal surface, forms a corrosion-inhibiting film thereon. The composition comprises an epoxy resin, and a petroleum sulfonate, usually in a hydrocarbon diluent. The composition can further comprise a polyamine, an alcohol or both. The composition is applied by contacting the metal surface with the composition as one solution or as a hydrocarbon solution of the epoxy resin and a solution comprising the petroleum sulfonate. The composition is particularly useful in the treatment of downhole metal surfaces in oil and gas wells to inhibit the corrosion of the metal.

Abstract: Method for the formation, processing, transportation and end use of a hydrocarbon-in-water emulsion.

Abstract: Production of at least a gaseous product containing a substantial amount of hydrogen sulphide via a bore-hole from an underground formation containing besides the hydrogen sulphide at least elemental sulphur by(a) injection of a liquid substantially consisting of hydrocarbons into the bore-hole or into the underground formation near to the end of the bore-hole;(b) producing a gaseous and a liquid fraction from the underground formation;(c) separating the gaseous fraction from the liquid fraction;(d) if necessary, separating an aqueous fraction of the product liquid fraction from the hydrocarbons-containing fraction;(e) heating the hydrocarbons-containing fraction preferably in the presence of hydrogen and a hydro-desulphurization catalyst, in order to remove elemental sulphur; and(f) reinjection of at least a part of the thus treated hydrocarbons-containing fraction into the bore-hole or into the underground formation near to the end of the bore-hole.

Abstract: The present invention relates to a method for drawing up a crude oil containing a great amount of wax or a high-viscosity crude oil. The method of the present invention is characterized by cracking or fractionating the crude oil which has been drawn up, in order to prepare a cracked oil or a gas oil, and by drawing up the crude oil, while injecting a part of the cracked oil or the gas oil into an oil well. According to the present invention, an efficient drawing operation can be achieved.

Abstract: A composition is provided which, when applied to a metal surface, forms a corrosion-inhibiting film thereon. The composition comprises an epoxy resin, and a petroleum sulfonate, usually in a hydrocarbon diluent. The composition can further comprise a polyamine, an alcohol or both. The composition is applied by contacting the metal surface with the composition as one solution or as a hydrocarbon solution of the epoxy resin and a solution comprising the petroleum sulfonate. The composition is particularly useful in the treatment of downhole metal surfaces in oil and gas wells to inhibit the corrosion of the metal.

Abstract: In an improved method for inhibiting the formation of scale in a well penetrating a subterranean formation for the production of fluids from said formation, said method including injecting at least one scale inhibitor into said formation through said well so that said scale inhibitor is thereafter slowly released from said formation to inhibit the formation of scale, the improvement comprising: injecting at least one polymeric material into said well in an amount effective to prolong said scale formation inhibition, said polymeric material having a composition different from said scale inhibitor and being a copolymer derived from at least one first monomer having a maleic moiety and at least one second monomer selected from the group consisting of acrylic acid, methacrylic acid and mixtures thereof.

Abstract: A method of improving production of heavy crude oil from a well by mixing a first solution of water soluble surfactant and water, and preferably forming a mixture of the first solution and an oil solvent, and pumping the mixture into the well to mix with the heavy crude oil to be produced. A desirable surfactant is a water soluble ethoxylated nonylphenol and a desirable oil solvent is kerosene distillate.

Abstract: The present invention discloses an apparatus and method for periodically and automatically introducing fluid into a producing well through a tubing drain valve in the production tubing. The apparatus and method of the present invention employ a tubing drain valve actuated to its open position by pressurizing the interior of the production string. The system further includes apparatus for introducing a fluid, e.g., a paraffin solvent or formation treating chemical, into the production tubing and into the formation through the opened tubing drain valve. After completion of this operation, the tubing drain valve is closed and production resumed by a mechanical actuator, preferably an actuator carried by the sucker rods for operating the downhole pump. A control device, including optional monitoring devices, provides a system for introducing such fluids at periodic intervals.

Abstract: A method for starting up the production of hydrocarbonaceous fluid from a wellbore which has been shut-in for a time such that the ratio of water to hydrocarbon present in the hydrocarbonaceous fluid in the wellbore is sufficiently high as to make it uneconomic to produce hydrocarbonaceous fluid from said wellbore, the improvement comprising heating the reservoir around said wellbore and the hydrocarbonaceous fluid contained therein suficiently to cause the said hydrocarbonaceous fluid to be substantially less viscous and to cause at least some thermal expansion of said hydrocarbonaceous fluid whereby the water to hydrocarbon ratio is decreased to a value at which hydrocarbonaceous fluid can be economically produced from said wellbore and thereafter starting up production of hydrocarbonaceous fluid from said wellbore.

Abstract: A composition is provided which, when applied to a metal surface, forms a corrosion-inhibiting film thereon. The composition comprises the reaction product of a first component selected from an epoxy resin, an epoxidized alkene and a substrate having at least one displaceable halogen, and a second component comprising a monomercaptan in a hydrocarbon diluent. The composition is applied by contacting the metal surface with the composition. The composition is particularly useful in the treatment of down-well metal surfaces in oil and gas wells to inhibit the corrosion of the metal under highly corrosive conditions, and is effective even in the presence of polymeric permeability control agents such as aqueous polyacrylamides.

Abstract: Corrosion inhibiting of well production tubing, such as for an oil or gas well, is provided in a simple and effective manner without interrupting well production. A portable skid has a chemical tank, water tank, pumps, conduits, and controls mounted on it, and is transported to the production well site. A mix of corrosion-inhibiting chemical and water is supplied from the tanks to an end conduit, and the end conduit is connected to an injection string, or an annulus associated with a side mandrel, of the production well. A computer control is provided for controlling the pumps, and other components, so that any desired amounts and proportions of a mix of chemical and water is continuously injected into the well to inhibit corrosion of the well production tubing string without interruption of production.

Abstract: Chemical treating liquids (e.g. scale inhibitors) are dispersed in the producing interval by (a) extending a slim tube along the production tube into connection with a more rigid tube extending below a dual packer and the production tube, and (b) inflowing a mixture of gas-saturated treating liquid and gas through the slim tube.

Abstract: A gravity system, the only moving parts of which are the valves, uses only the system pressures, and opening and closing of valves to feed treatment liquids to an oil well. The chemical treatment liquid is stored in a drum above a volume chamber. The volume chamber has five lines connected to it, each with a valve. A feed line with a feed valve connects the volume chamber to the treatment drum. A vent line with a vent valve vents the top part of the volume chamber to the atmosphere. A liquid pressure line with a pressure valve connects the flow line (connected to the oil well eduction tube) to the volume chamber. A flush line with a flush valve connects the bottom of the volume chamber to the well annulus. A gas line with a gas valve connects the volume chamber to the annulus. When the vent valve and feed valve are open and all other valves are closed, the volume chamber will fill with liquid by gravity from the chemicals within the treatment drum.

Abstract: A method and apparatus for distributing fluids within a subterranean borehole wherein a submersible pump is introduced into the borehole at a first location. An intake port of the pump is connected to the first end of an intake duct having an unconnected second end located at a second location within the wellbore from which location fluid is to be withdrawn. An output port of the pump is connected to a first end of a second duct having an unconnected second end at a third location within the wellbore into which location fluid is to be introduced. By activating the pump, fluids, such as scale and corrosion inhibitors, are distributed from above the intake of a production pump to as low in the borehole as is required to protect wellbore contents.