Described herein are surfactant compositions for use in oil and gas operations. The surfactant compositions are stable under harsh conditions, including in formations that exhibit high salinity, high temperature, and/or high H2S concentration. Also provided are methods of using these compositions. Specifically an aqueous composition comprising: (i) a surfactant package, wherein the surfactant package comprises: (a) a surfactant comprising a branched, unbranched, saturated, or unsaturated C6-C32:80(0-65):PO(0-65):EO(0-100)-X having a concentration within the aqueous composition of from 0.05%-5% by weight, based on the total weight of the aqueous composition, wherein there is at least one BO, PO, or EO group, and wherein X comprises a sulfonate, a disulfonate, a carboxylate, a dicarboxylate, a sulfosuccinate, a disulfosuccinate, or hydrogen: and (b) olefin sulfonate and/or a disulfonate; and (ii) water.

Scavenging chemicals used in mitigation treatments of hydrogen sulfide in hydrocarbon streams often continue to react and form polymers that foul the processing system. Disclosed herein are methods for determining if a scavenging chemical mitigator, or its reaction or degradation product, will polymerized during or after mitigation treatments. This information allows for the optimization of mitigation treatments that pre-emptively control or prevent polymer formation. Such pre-emption measures reduce the cost and time related to remedial actions to treat polymer-fouled equipment.

Disclosed are succinic anhydride-derived polyester compounds used in compositions and methods for inhibiting corrosion.

Methods for delivering treatment chemicals into a subterranean formation using treatment fluids that include nanoemulsions are provided. In some embodiments, the methods include providing a treatment fluid including an aqueous base fluid and a nanoemulsion including a water-soluble internal phase, a water-soluble external phase, and a surfactant, the nanoemulsion being formed by mechanically-induced shear rupturing; and introducing the treatment fluid into at least a portion of a subterranean formation at or above a pressure sufficient to create or enhance at least one fracture in the subterranean formation.

A method for the fracking or stimulation of a hydrocarbon-bearing formation, said method comprising the steps of: providing a wellbore in need of stimulation; inserting a plug in the wellbore at a predetermined location; inserting a perforating tool and a spearhead or breakdown acid into the wellbore; positioning the tool at said predetermined location; perforating the wellbore with the tool thereby creating a perforated area; allowing the spearhead acid to come into contact with the perforated area for a predetermined period of time sufficient to prepare the formation for fracking or stimulation; removing the tool from the wellbore; and initiating the fracking of the perforated area using a fracking fluid. Also disclosed is a corrosion inhibiting composition for use with the acid composition.

Use of complex polyester amines and polyester quaternary ammonium compounds as corrosion inhibitors for metal surfaces, and a method for protecting a metal surface from corrosion by contacting the metal surface with said corrosion inhibitor.

The present invention discloses a preparation method for the plant-based nano corrosion inhibition bactericide for oilfield, comprising the following steps: Step 1. Prepare the aloin liquid; Step 2. Stir the carbon nanotube, hydroxyethyl methacrylate and acrylic acid to react for 4 h at a constant temperature of 80° C. to get the carbon nanotube after fiber treatment, namely the modified carbon nanotube; Step 3. Mix the aloin liquid with imidazoline-ammonium-salt, add acetonitrile, and then add modified carbon nanotube, increase the temperature to 95° C. stir and react for 12 hours, and filter after naturally cooling down to room temperature and get the carbon nanotube loaded with bactericide; Step 4. Stir the carbon nanotube loaded with bactericide, diphenylmethane diisocyanate and polycaprolactone to react for 6 hours at a constant temperature of 95° C. and in the reaction process, continuously inject helium to get the target bactericide.

Polymeric systems useful for maintaining particle dispersions for extended periods of time.

Heavy fluids are made from calcium bromide and at least one hydrogen bond donor such as a low molecular weight polyol or an organic acid. The combination of a hydrogen bond donor and calcium bromide as a hydrogen bond acceptor in an appropriate molar ratio forms a higher density clear completion fluid at a low temperature not otherwise obtainable with heavy aqueous solutions of calcium bromide such as are used in oilfield wells. A method of making the fluid comprises mixing calcium bromide with the polyol(s) in the presence of water and then reducing the water content, thus forming a heavy fluid. A crystallization inhibitor such as nitrilotriacetamide or a particulate silicate is included in the formulation. When the heavy fluid “freezes,” its physical form is somewhat amorphous and pumpable rather than crystalline. The heavy fluid is useful as a drilling fluid as well as a completion fluid and for other purposes in oil recovery processes where extreme density is beneficial.

An aqueous synthetic acid composition is disclosed for use in oil industry activities, the composition comprising: lysine and hydrogen chloride in a molar ratio ranging from 1 to 1:12.5, preferably from more than 1:5 to 1:8.5. The composition can also further comprise a metal iodide or iodate; an alcohol or derivative thereof. The composition demonstrates advantageous properties over known synthetic acids at temperatures above 90° C. The composition is useful in various oil and gas industry operations. Preferred embodiments of the composition provide substantial advantages in matrix acidizing by increasing the effectiveness of wormholing as compared to conventional mineral acids such as HCl.