Abstract: Alcohol based hydraulic fracturing fluids useful for treating oil and gas wells are disclosed. The fluids are compatible with carbon dioxide, and comprise an alcohol, a polymer, a crosslinking agent, and a breaker. Hydroxypropyl guar with a molar substitution of about 1.2 to about 2.2 is identified as a presently preferred polymer.

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 method of treating a well consists of introducing into the wellbore a biodegradable fluid system containing a blend of lactic acid ester, such as ethyl lactate, and a fatty acid ester, such as methyl soyate. The fluid system may be further in the form of a microemulsion that is formed by combining a blend with one or more emulsifiers, an alcohol, and water. 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.

Abstract: The present invention provides a cementing system and method for wellbores by cementing an annulus between a wellbore casing and a wellbore. In at least one embodiment, the invention includes a landing collar defining a restricted passage, a wellbore casing defining a passage coupled to the landing collar, a top cementing plug for sealingly engaging the wellbore casing, a bottom cementing plug for sealingly engaging the wellbore casing, and a fluid injection assembly coupled to the wellbore casing for injecting fluidic materials into the wellbore casing and controllably releasing the top cementing plug and the bottom cementing plug into the wellbore casing. The bottom cementing plug includes a plug body defining a plug passage, a frangible membrane for sealing the plug passage, and a one-way valve for controlling the flow of fluidic materials through the plug passage. The invention also includes the bottom cementing plug and methods for operation.

Abstract: Compositions and methods for the inhibition of salt formation in oil and gas wells are disclosed. In particular, nitrilotriacetamide and its salts are effective at treating existing salt formations, and in inhibiting formation of new deposits.

Abstract: A well treating composition contains an aqueous acid and at least one relatively lightweight proppant, preferably having an apparent specific gravity (ASG) less than or equal to 2.45. The acid fracturing composition may used to acid fracture a hydrocarbon reservoir within a subterranean formation of an oil or gas well. The composition may further be used to stimulate the production of hydrocarbons. The proportion of relatively lightweight proppant to acid in the composition is such that the dimensional fracture conductivity (CfD) is in excess of 1.0. The aqueous acid typically has an ASG substantially equal to the ASG of the relatively lightweight particulate. As such, the relatively lightweight particulate is suspended in the aqueous acid.

Abstract: The present invention provides a bi-directional ball seat and method of use. In at least one embodiment, the present invention provides a fluid control system that includes a radial protrusion that can be selectively engaged and disengaged upstream and/or from a ball seat. For example, a ball can be placed in a passageway, engaged with a downstream ball seat, and the radial protrusion radially extended into the passageway distally from the seat relative to the ball. A reverse movement of the ball is restricted by the active radial movement of the radial protrusion into the passageway. The control system can be used to control a variety of tools associated with the well. Without limitation, the tools can include crossover tools, sleeves, packers, safety valves, separators, gravel packers, perforating guns, decoupling tools, valves, and other tools know to those with ordinary skills in the art.

Abstract: A subterranean formation having natural fractures, which is to be subjected to hydraulic fracturing, is first pre-treated with an ultra lightweight (ULW) proppant having an average particle size between from about 12/20 to about 40/70. The small ULW proppant flows into the natural fractures and packs the fractures. The formation is then subjected to hydraulic fracturing. The pre-treatment serves to enhance the effective propped fracture length of the formation during the hydraulic fracturing by reducing the loss of fluid from the subsequently pumped fracturing fluid. The method is applicable to hydrocarbon bearing formations as well as non-hydrocarbon bearing formations and has particular applicability to coal beds.

Abstract: Homopolymers and copolymers of an esterified reaction product of an epoxidized mono-hydroxyl alcohol and a free radical polymerizable monomer are highly effective demulsifying agents. The molecular weight of the polymer is between from about 10,000 to about 500,000. The epoxidized mono-hydroxyl alcohol is preferably a reaction product of a C6–C30 linear or branched alcohol and an alkylene oxide. The alkylene oxide is preferably either ethylene oxide, propylene oxide or butylenes oxide or a mixture thereof. The free radical polymerizable monomer is preferably a vinyl aromatic compound or an acrylic or methacrylic based monomer. The polymer preferably comprises a micellar assembly. Such polymers are highly effective in demulsifying crude oils having API gravities of from 8 to 28 or a crude oil having a viscosity between from about 3 to about 10,000 CPS @ at 25° C.

Abstract: A method for completing a well in a single trip, including: inserting a completion tool assembly into the well, the completion tool assembly having a gravel packing assembly and a service tool assembly slidably positioned substantially within an interior cavity in the gravel packing assembly; removably coupling the service tool assembly and the gravel packing assembly; plugging at a first location, whereby fluid is blocked from flowing through the interior channel; diverting fluid blocked by the plugging at the first location through a first fluid flow path to an exterior of the completion tool assembly; circulating a gravel pack slurry through the completion tool assembly; plugging at a second location, whereby fluid is blocked from flowing through the interior channel; diverting fluid blocked by the plugging at the second location through a second flow path that reenters the interior channel at a location distal of the first and second plugging locations; and circulating a filter cake stimulating fluid thro

Abstract: Methods are provided for fracturing subterranean formations using fluids having substantially reduced polymer loadings that have performance equivalent to conventional fluids. Reduced polymer loadings provide significant advantages such as reduced treatment costs and less damage to the fracture sand pack and surrounding subterranean formations.

Abstract: A storable cement system comprises a suspending agent, a cement spacer and water. The composition may further optional contain a surfactant and/or an organic solvent and/or a weighting material. The suspending agent is preferably a carrageenan or scleroglucan. The cement system may be stored for an extended period of time prior to being interposed between a cement slurry and a drilling fluid. As such, the aqueous cement system may be made off-site and used when desired for preventing contact between non-compatible hydrocarbonaceous and aqueous fluids.

Abstract: A formation treating fluid comprises one or more borate esters, a liquid carrier and, one or more cross linkable polymer wherein the formation treating fluid has an alkaline pH when the formation treating fluid is positioned in a formation. The formation treating fluid is useful in high temperature operations such as hydraulic fracturing.

Abstract: A well treatment fluid composition comprises a solvent (such as water), a polymer soluble or hydratable in the solvent, a crosslinking agent, an inorganic breaking agent, and an ester compound. Preferably, the hydratable polymer is a polysaccharide, such as galactomannan, cellulose, or derivatives thereof. The crosslinking agent is preferably a borate, titanate, or zirconium-containing compound. The inorganic breaking agent is preferably a metal-based oxidizing agent, such as an alkaline earth metal or transition metal-based oxidizing agent. The ester compound is preferably an ester of polycarboxylic acid, such as an ester of oxalate, citrate, or ethylenediamine tetraacetate. One example of a suitable ester compound is acetyl triethyl citrate.

Abstract: Wireless local area networks (“wireless networks”) used to interrelate individual mobile nodes, and having the capability of automatically establishing and/or modifying functionality of a network in response to the characteristics and/or identity of the nodes connected to the network at a given time. The wireless networks may be mobile, and may be employed in applications using service vehicles, such as truck, skid and trailer mounted equipment used in the well servicing industry, delivery or maintenance trucks, railroad service vehicles, aircraft, or off-shore service vehicles.

Abstract: The present invention provides a return port cover that can close and open a return port separate from tubing movement caused by stretching or contracting under stress or other induced pipe movement from downhole conditions. For example, the return port cover can assist in preventing pack “fluffing” by preventing unintended fluid communication through an associated downhole tool regardless of the position of a circulating valve means. The return port cover can be biased, so that in one position it closes the port and in another position opens the port based on relative tubing placement at different portions of the fracturing operation or other well treatment operations.

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 gravity valve for a downhole tool for use in a subterranean well is described, as is a method of use thereof. The gravity valve is adapted to control the flow of a downhole fluid through the downhole tool. The gravity valve typically includes a plunger and a seat. The plunger may embody a substantially non-spherical end that is adapted to mate with a complementary receiving end on the seat. The increase surface area of contact between the plunger and the seat acts to improve the seal therebetween, reduce the stresses thereon, and improve the performance of the gravity valve in general. The components of the gravity valve may be constructed of materials, which are selected based on the specific gravity of the materials in comparison with the specific gravity of the downhole fluid for a given application. A method of constructing and utilizing the gravity valve is disclosed.

Abstract: An isolation assembly for use with coiled tubing is described. The isolation assembly has a check valve for providing selective fluid communication through from the coiled tubing, through the isolation assembly, and into a downhole tool, such a straddle packer. The isolation assembly includes a shuttle moveable within a housing, and plurality of ports to selectively provide fluid communication from within the isolation assembly below the check valve, through the ports, and into the annulus, thus allowing selective surface-controlled equalization of downhole equipment. Also described is a bottom hole assembly including the isolation assembly. An improved method of fracing a formation includes providing a check valve, thus improving the life of the coiled tubing and the safety of the operation, and reducing the time to perform a given downhole operation.

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.