Drilling fluid compositions and methods for using drilling fluid compositions are provided with enhanced lubricating properties that include an aqueous-based fluid, one or more drilling fluid additives, and a lubricating additive. The lubricating additive may be an epoxidized α-olefin and the drilling fluid may include the lubricating additive in an amount ranging from about 1 ppb to about 20 ppb. Methods for using the drilling fluid compositions may further include mixing an aqueous base fluid with one or more drilling fluid additives and a lubricating additive, wherein the lubricating additive includes epoxidized α-olefin and the drilling fluid may include the lubricating additive in an amount ranging from about 0.5 ppb to about 20 ppb, and introducing the drilling fluid to a subterranean formation.

Provided are a polyaspartic acid derivative and a preparation method and use thereof as a lubricant, and a water-based drilling fluid and use thereof. The polyaspartic acid derivative has a structure shown in formula I, wherein, in the formula I, R.sup.1 is selected from the group consisting of —CH.sub.2—CH.sub.2—CH.sub.2—, —CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—, and —CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—; R.sup.2 is selected from the group consisting of —OH, —N—(CH.sub.2—CH.sub.2—OH).sub.2, —O—CH.sub.2—CH.sub.2—NH—CH.sub.2—CH.sub.2—OH, —NH—CH.sub.2—CH.sub.2—OH, and —O—CH.sub.2—CH.sub.2—NH.sub.2; and n and m are independently 8 to 17. ##STR00001##

Provided are a polyaspartic acid derivative and a preparation method and use thereof as a lubricant, and a water-based drilling fluid and use thereof. The polyaspartic acid derivative has a structure shown in formula I, wherein, in the formula I, R.sup.1 is selected from the group consisting of —CH.sub.2—CH.sub.2—CH.sub.2—, —CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—, and —CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—CH.sub.2—; R.sup.2 is selected from the group consisting of —OH, —N—(CH.sub.2—CH.sub.2—OH).sub.2, —O—CH.sub.2—CH.sub.2—NH—CH.sub.2—CH.sub.2—OH, —NH—CH.sub.2—CH.sub.2—OH, and —O—CH.sub.2—CH.sub.2—NH.sub.2; and n and m are independently 8 to 17. ##STR00001##

A wellbore fluid composition is provided that includes an aqueous base fluid and at least one ethylene ammonium salt having a number average molecular weight in a range of 250 to 500 grams per mole. A method of drilling a wellbore is also provided. the method includes circulating an aqueous drilling fluid into the wellbore while drilling, wherein the aqueous drilling fluid includes at least one ethylene ammonium salt. The aqueous drilling fluid further includes a pH value from 6.5 to 7.5. The method of drilling a wellbore further includes recovering shale cuttings while maintaining wellbore stability.

A wellbore fluid composition is provided that includes an aqueous base fluid and at least one ethylene ammonium salt having a number average molecular weight in a range of 250 to 500 grams per mole. A method of drilling a wellbore is also provided. the method includes circulating an aqueous drilling fluid into the wellbore while drilling, wherein the aqueous drilling fluid includes at least one ethylene ammonium salt. The aqueous drilling fluid further includes a pH value from 6.5 to 7.5. The method of drilling a wellbore further includes recovering shale cuttings while maintaining wellbore stability.

A microemulsion well stimulation compositions for flowback water recovery includes an aqueous system, a surfactant system, a solvent system, and optionally a winterizing system, where the solvent system includes a dibasic ester or a plurality of dibasic esters and the composition is non-flammable, non-combustible, non-hazardous, and/or environmentally friendly, while demonstrating comparable or superior flowback recovery performance compared to known water recovery formulations that utilize more flammable components.

A microemulsion well stimulation compositions for flowback water recovery includes an aqueous system, a surfactant system, a solvent system, and optionally a winterizing system, where the solvent system includes a dibasic ester or a plurality of dibasic esters and the composition is non-flammable, non-combustible, non-hazardous, and/or environmentally friendly, while demonstrating comparable or superior flowback recovery performance compared to known water recovery formulations that utilize more flammable components.

A method of improving rheological properties of a divalent brine based downhole treatment fluid at an elevated temperature comprises adding to the divalent brine based downhole treatment fluid a rheological modifier, which comprises a carboxylic acid ester, or a phosphate ester blended with an ethoxylated glycol, or a combination comprising at least one of the foregoing in an amount effective to improve the rheological properties of the divalent brine based downhole treatment fluid at a temperature of greater than about 200° F. The divalent brine based downhole treatment fluid comprises calcium bromide, calcium chloride, zinc bromide, zinc chloride, or a combination comprising at least one of the foregoing.

A method of improving rheological properties of a divalent brine based downhole treatment fluid at an elevated temperature comprises adding to the divalent brine based downhole treatment fluid a rheological modifier, which comprises a carboxylic acid ester, or a phosphate ester blended with an ethoxylated glycol, or a combination comprising at least one of the foregoing in an amount effective to improve the rheological properties of the divalent brine based downhole treatment fluid at a temperature of greater than about 200° F. The divalent brine based downhole treatment fluid comprises calcium bromide, calcium chloride, zinc bromide, zinc chloride, or a combination comprising at least one of the foregoing.

A system and method for generating water concentrated in calcium bromide from produced water, to provide for drilling fluid having the calcium bromide. The technique includes flowing the produced water through a bed of ion-exchange resin to sorb bromide ions from the produced water onto the ion-exchange resin, and then regenerating the ion-exchange resin to desorb the bromide ions for combination with calcium ions to acquire an aqueous solution with calcium and bromide.