The invention provides a method for employing the total product stream from hydrolysis of triglycerides comprising fatty acids, glycerin and water to address at the environmental issues associated with drilling, completion and hydrofracturing wells employed for recovery of subterranean hydrocarbon deposits in an area of shale formation.

Stimulation treatments are designed and performed in a manner that takes into account radial acid flow into the formation. A reservoir core plug is selected and a liner core flow test is performed. The core flow test comprises measuring a flowing fraction, injecting into the core plug a treatment volume of at least one candidate stimulation fluid at an injection rate at reservoir conditions, and measuring an effective reaction rate constant. The linear flow data are then scaled to radial flow. A skin, an acid concentration at a wormhole tip and a fluid velocity at a wormhole tip are calculated. A stimulation treatment is then performed. The method can also be performed on analog cores. The stimulation treatment may be matrix acidizing, fracture acidizing or acidizing natural fractures.

A method of quantifying a viscoelastic effect of a polymer on residual oil saturation (S.sub.or) including calculating an extensional capillary number (N.sub.ce) using flux, pore-scale apparent viscosity, and interfacial tension to account for the polymer's viscoelastic forces that are responsible for S.sub.or reduction. The polymer is used polymer flooding during enhanced oil recovery. An extensional capillary number is calculated for a plurality of polymer materials, which are then compiled in a database. Also provided is a reservoir simulator for predicting the S.sub.or reduction potential of the viscoelastic polymer, which includes a database of calculated extensional capillary numbers for a plurality of polymers. The database includes a curve generated from the calculated extensional capillary numbers for a plurality of polymers properties, flux rates, formation nature, oil viscosities, and rheological behaviors.

A system and method for hydraulic fracturing a subterranean formation with fracturing fluid to generate fractures, and intermittently adjusting a characteristic of the fracturing fluid conveying proppant to form pillars of proppant in the fractures.

A viscoelastic surfactant (VES) for a self-diverting acid under high temperature has a structural formula shown as formula (I), wherein, n is saturated hydrocarbon with 2 to 8 carbon atoms; R.sub.1 is saturated or unsaturated hydrocarbon with 18 to 28 carbon atoms; R.sub.2 and R.sub.3 are independently methyl, ethyl or hydrogen, and R.sub.2 and R.sub.3 can be the same or different; and X.sup.− is any one of Cl.sup.−, Br.sup.−, CO.sub.3.sup.2−, SO.sub.4.sup.2−, HCOO.sup.− and CH.sub.3COO.sup.−. The method for preparing the surfactant includes subjecting a fatty acid and an organic amine to acid-amine condensation to obtain an intermediate. The intermediate reacts with a metal hydride to obtain a fatty amine. Then, an acid solution is used to protonate the fatty amine to obtain an ultra-long-chain viscoelastic cationic surfactant. The present invention also provides use of the surfactant as a thickener for a self-diverting acid.

A method comprising (a) contacting a suspension composition, water, and optionally one or more additives to form a wellbore servicing fluid at a location proximate a wellsite; wherein the suspension composition comprises a particulate material, an organic carrier fluid, and a suspension viscosifier; and (b) placing the wellbore servicing fluid in a wellbore penetrating a subterranean formation. The wellsite comprises an offshore platform, a floating vessel, or combinations thereof; and wherein the wellbore is offshore. A suspension composition comprising a particulate material, an organic carrier fluid, and a suspension viscosifier; wherein the particulate material is substantially insoluble in the organic carrier fluid; wherein the particulate material comprises a water-interactive material and/or a water-insoluble material; and wherein the organic carrier fluid comprises a glycol and/or a glycol ether.

The present invention relates to a carbonate reservoir filtration-loss self-reducing acid fracturing method. The carbonate reservoir filtration-loss self-reducing acid fracturing method comprises the steps: (1) calculating a fracture pressure and a fracture extension pressure of a reconstructed reservoir; (2) injecting an agent A into a stratum under a pressure higher than the stratum fracture pressure, so that fractures are generated on the stratum; (3) injecting an agent B into the stratum under a pressure higher than the stratum fracture pressure, such that the agent B extends the fractures and communicates with a natural fracture net; (4) pumping an acid liquor system agent C with a high etching power into the stratum under a pressure higher than the extension pressure but lower than the fracture pressure to improve the conductivity of the fractures; (5) injecting a displacing liquid agent D under a pressure lower than the stratum fracture pressure to jack acid liquor in a well casing into the stratum; and (6) shutting down a well and performing flow-back. The agent A is a gel acid or VES acid, the agent B is a filtration-loss self-reducing gel acid or filtration-loss self-reducing VES acid, the agent C is closed acid, and the agent D is a displacing liquid. According to the method of the present invention, precipitation type solid filter cakes are formed on wall surfaces of the fractures by utilizing a filtration-loss self-reducing system, so as to perform temporary blocking to reduce the filtration loss. The technology is simple with easy injection, and the filtration-reducing agent is easy to disperse and flow back, and the method is safe and environment-friendly.

Methods may include using geometrical and mechanical properties to generate a model of one or more intervals of a wellbore; designing a fluid pumping schedule for a wellbore treatment fluid system; simulating flow of a fluid system containing solids using the model of the one or more intervals of the wellbore, wherein simulating comprises determining the flow rate distribution within the wellbore and modeling the settling and resuspension of the solids within the flow of the fluid system; and updating the fluid pumping schedule based on the output determined from the simulated flow of the fluid system. Methods may also include determining the critical velocity of the fluid system for various concentrations of one or more of solids and additives; and selecting the concentration of the one or more of solids and additives based on the critical velocities determined.

Described herein are methods for treating a subterranean formation penetrated by a wellbore with a retarded acidizing fluid containing an acid and an acid retarding agent, the concentrations of which are adjusted based on measured parameter values of the formation. Also described is a method for treating a subterranean formation by introducing an acid to the formation following the introduction of an acid retarding agent to the formation. Also described is a method for acid fracturing a subterranean formation including reducing the concentration of an acid retarding agent contained in a retarded acidizing fluid over the course of the acid fracturing operation.

A fracturing fluid may include a first surfactant and a second surfactant. The first surfactant may have a structure represented by formula (I): ##STR00001##
wherein m is an integer ranging from 2 to 3, and n, o, and k are each, independently, integers ranging from 2 to 10. The second surfactant having a structure represented by Formula (II): ##STR00002##
wherein R.sup.2 is a C.sub.15-C.sub.27 hydrocarbon group or a C.sub.15-C.sub.29 substituted hydrocarbon group, R.sup.3 is a C.sub.1-C.sub.10 hydrocarbon group, and p and q are each, independently, an integer ranging from 1 to 4. Methods of treating a hydrocarbon-bearing formation include injecting the fracturing fluid in the hydrocarbon-bearing formation, the fracturing fluid being configured to transport a proppant in fractures of the hydrocarbon-bearing formation.