Abstract: A polymer enhanced foam comprising a polymer selected from a synthetic polymer or a biopolymer, a surfactant, an aqueous solvent and a gas is injected into a fractured subterranean formation via a first well in fluid communication with the formation and preferentially enters fractures present in the formation. The injected polymer enhanced foam promotes the recovery of liquid hydrocarbons from said formation via the first well or a second well in fluid communication with the formation.

Abstract: Method and means for preventing fluidization or mobilization of a gravel pack in a fluid producing well as a result of increased fluid pressure caused by a well shut-in or other pressure surge. A pressure relief valve in the form of a check valve is provided in a tubing string below a packer surrounding the string and above the top of the gravel pack. The check valve is held in closed position by a biasing force, such as a spring, which is less than the pressure which will cause mobilization or fluidization of the gravel pack. A pressure surge such as a well shut-in or flow rate decrease increases tubing pressure which causes the check valve to open, thereby relieving the pressure in the gravel pack to a point below the critical level.

Abstract: A method of selectively and variably positioning tubing within the generally horizontal section of a horizontally drilled well. A tubing string having a guide shoe secured to the end thereof is inserted into a portion of the horizontal section of a horizontal well. Smaller diameter tubing is then inserted through the tubing string and past guide shoe into the generally horizontal section. The smaller diameter tubing can be inserted to a point proximate the end of the horizontal section of the well or intermediate between the end and the guide shoe. The subterranean formation surrounding the generally horizontal section may be stimulated or treated by injecting a fluid via the smaller diameter tubing.

Abstract: A foam is provided having utility for improving sweep efficiency in subterranean oil-bearing formations and having specific utility for conformance improvement treatments and mobility control in such formations. The foam is a gel medium having a gas dispersed therein. The gel medium is made up of a crosslinkable polymer, a crosslinking agent, a surfactant and a liquid solvent.

Abstract: A sealed valve body housing a rotary valve rotated by a spindle. The spindle is connected to a disc mounted in a chamber in the valve body adjacent a valve body wall. Polyphase drive coils on the valve body wall induce a current in the disc, causing it to rotate. A pulse sensor mounted on the valve body detects the rotative position of the disc and a counter signals the power source to stop movement of the valve. The periphery of the disc is notched to permit the pulses to pass through the rotating disc and be counted. The torque of the disc can be increased through use of more sets of coils, more discs or gears interconnecting the spindle and the rotary valve.

Abstract: A composition for use as a road base or levee fill. The composition comprises catalytic cracking catalyst particles in the size range of 1 to 200 microns and a binder the type and amount of which depend on the end use. Hydrated lime is employed as the binder in road base construction while hydrated lime, portland cement, fly ash or mixtures of fly ash and portland cement can be used in levee construction. The spent catalyst particles are present in amounts of 80% to 96% and the binder is present in amounts of 4% to 20%, both percentage ranges being determined according to the dry weight of the composition.

Abstract: A relatively high molecular weight polyvinyl sulfonate and a process for inhibiting scale deposition, particularly inorganic sulfate such as barium sulfate, wherein an aqueous fluid present in or produced from a subterranean formation is contacted with an aqueous solution having a relatively high molecular weight polyvinyl sulfonate dissolved therein. The aqueous fluid has a pH equal to or less than 6.0 and the polyvinyl sulfonate has a molecular weight of from about 9,000 to about 30,000.

Abstract: Reversible crosslinked polymer gels are prepared by adding a degelling agent precursor to a gelation solution during initial preparation. The precursor is integrated into the resulting gel and undergoes hydrolysis to transform into an active degelling agent which reverses the gel. The process has specific utility to hydrocarbon recovery applications where in situ gels are difficult to contact with conventional reversing agents.

Abstract: A process is provided for sand consolidation treatment in a subterranean hydrocarbon-bearing formation in fluid communication with a hydrocarbon production well bore. An immature flowing gel is injected through the well bore into a treatment zone of the formation and followed by an overdisplacement fluid which displaces a portion of the immature gel from the zone. Displacement of a portion of the immature gel from the zone establishes flow pathways through the zone for subsequent hydrocarbon production while the gel remaining in the zone matures and effectively consolidates the sand therein.

Abstract: Degasification of liquid sulfur produced by the Claus process to remove hydrogen sulfide. The liquid sulfur is caused to flow continuously through a vessel where it is contacted by a counter-flowing inert gas, thereby stripping hydrogen sulfide from the sulfur. Nitrogen and air are preferred examples of inert gas which can be used in the method.

Abstract: A process for in-situ enrichment of gas used in miscible flooding in a subterranean hydrocarbon-bearing reservoir. A drive gas such as methane, lean natural gas, nitrogen, carbon dioxide or mixtures thereof is used to immiscibly displace formation hydrocarbons. After gas breakthrough the produced fluid is separated into oil and gas components. The separated gas, which has been enriched with intermediate hydrocarbon compounds extracted from the formation hydrocarbons, is mixed with the drive gas injected into the reservoir so as to enrich the injected gas sufficiently to cause miscible displacement of the formation hydrocarbons. When the drive gas is carbon dioxide, methane and/or nitrogen may be extracted from the separated gas prior to being mixed with the drive gas.

Abstract: Method and means for redistributing fluid flow through a catalyst bed in a reactor by applying uniform flow resistance. A mat to which a series of uniformly spaced disks are adhered is placed within the catalyst bed. The disks are formed of a material capable of withstanding the temperatures within the reactor, while the mat is formed of a material which is not. The mat is destroyed by the heat of the reactor, leaving the disks in place. Localized high flow rates are smoothed out by the flow resistance provided by the disks, with flow taking place between the disks. Since the disks are small relative to the opening used to dump the spent catalyst, special consideration for disk recovery and handling are not necessary as the disks flow out the opening with the spent catalyst.

Abstract: An offshore submersible jacket assembly having bouyancy means at the lower portion of the jacket support legs. Relatively short pile sleeves are attached in a cluster to a support leg by shear plates extending generally along the length of the pile sleeves, each sleeve being connected to the leg by a pair of spaced shear plates. Upper and lower transverse plates seal off the ends of the spaced shear plates, creating airtight compartments.

Abstract: The present invention is a process for selectively plugging high permeability zones of a subterranean hydrocarbon-bearing formation by enhancing the delay associated with the in situ formation of a polymer gel. The process comprises predetermining a gelation delay time based on a formation's temperature, permeability and porosity, the distance from the well bore a region to be plugged is located, and a volumetric rate of gelation fluid injection. A gelation solution is then prepared comprising polyacrylamide a polyvalent metal carboxylate crosslinking agent, a gelation delaying agent and a buffer with a pKa of about 3.5 to about 6.8. Gelation delays are achieved by selecting the polyacrylamide concentration, delaying agent concentration and type, and buffer concentration and type, for given formation conditions. Delay times can range from several hours to several weeks at formation temperatures near 176.degree. F. (80.degree. C.

Abstract: Undesirable fluid flow is inhibited between a near well bore interval and an underlying aquifer in fluid communication therewith. A permeability-reducing material is injected into the near well bore interval and a portion of the material is selectively overdisplaced out into the formation by means of a low density gas subsequently injected into the interval. The gas desirably restores hydrocarbon productivity or fluid injectivity to the interval while the permeability-reducing material remaining in the interval inhibits fluid communication between the interval and the aquifer.

Abstract: A method of gravel packaging a well penetrating and in fluid communication with a subterranean formation or zone by sealing the apertures of a gravel pack liner, except near the bottom of the liner, against entry of slurry fluid. This prevents gravel from clogging the apertures or bridging the annulus between the liner and the well bore. An immobile gel provides the sealing function, and a breaker eventually breaks the gel, thereby permitting removal of the gel and unblocking the apertures. The gel is formed from a suitable liquid composition containing the gel breaker, and may be applied to the liner prior to lowering the liner and wash pipe into the well bore.

Abstract: A method of determining a numerical index from a cored well that corresponds to the performance data of a portion of a reservoir and a method of extrapolating the performance of such portion of a reservoir to the entire reservoir through use of the numerical index. Selected variables which affect fluid flow in the reservoir are compared by a statistical analysis computer program to performance data of the computer simulated portion of the reservoir after both the data and variables have been normalized to dimensionless values. The resulting numerical index is computed for the cored wells both inside and outside the small reservoir area, and a contour or iso-index map is drawn. Well performance outside the simulated area can be compared to expected performance through the numerical index values.

Abstract: Selective permeability reduction is achieved in a heterogeneous treatment zone of a subterranean hydrocarbon-bearing formation by initially placing a nonselective permeability-reducing material in the high and low permeability regions of the treatment zone. Thereafter, a permeability-restoring agent is placed in the regions behind the permeability-reducing material. The agent contacts all of the material in the low permeability region, reacting with it to restore permeability thereto. However, the agent is consumed by reaction before it contacts all of the material in the high permeability region, thereby leaving a sufficient amount of material in the high permeability region to achieve selective permeability reduction therein.

Abstract: A process for retorting oil shale in a vertical retort. Recycle gas containing steam and produced gas is separated from the retort off-gas and used to heat the oil shale. The steam is present in amount by volume of the recycle gas of at least 40% and preferably 70%. The minimum particle size of the oil shale is such that the particles are retained on a screen having 1/4 inch openings. The maximum particle size is such that the particles are capable of passing through a screen having 3 inch openings.

Abstract: A process for restoring the injectivity of a well penetrating and in fluid communication with a subterranean formation wherein an aqueous treating solution comprising a mixture of an aqueous solution having no more than 30 weight percent of hydrogen peroxide dissolved therein and a mutual solvent is injected via the well to contact polymer accumulation so as to degrade and disperse same. The mutual solvent comprises alcohol, aromatic hydrocarbon, and an alkyl or alkylaryl polyoxyalkylene phosphate ester surfactant.