In one embodiment, a spacer fluid may comprise a base fluid and a surfactant package. The surfactant package may comprise one or more surfactants, where the surfactant package comprises a first surfactant having the chemical structure R(OC.sub.2H.sub.4).sub.xOH. R may be a hydrocarbyl group having from 9 to 20 carbon atom, and x may be an integer from 5 and 15. The first surfactant may have a hydrophilic-lipophilic balance (HLB) of from 12 to 13.5.

In one embodiment, a spacer fluid may comprise a base fluid and a surfactant package. The surfactant package may comprise one or more surfactants, where the surfactant package comprises a first surfactant having the chemical structure R(OC.sub.2H.sub.4).sub.xOH. R may be a hydrocarbyl group having from 9 to 20 carbon atom, and x may be an integer from 5 and 15. The first surfactant may have a hydrophilic-lipophilic balance (HLB) of from 12 to 13.5.

Drilling fluid compositions include invert emulsion fluids having an oleaginous phase, an aqueous phase, and an emulsifier composition that includes an ethoxylated alcohol compound and a polyaminated fatty acid compound. The ethoxylated alcohol compound has the formula R.sup.1(OCH.sub.2CH.sub.2).sub.nOH, where R.sup.1 is a hydrocarbyl group having from 8 to 22 carbon atoms and n is from 1 to 8. The ethoxylated alcohol compound has a Hydrophilic-Lipophilic Balance (HLB) of less than or equal to 6. The polyaminated fatty acid compound has the formula R.sup.2CONHCH.sub.2CH.sub.2N(COR.sup.2)CH.sub.2CH.sub.2NHCOR.sup.3, where R.sup.2 is a hydrocarbyl group having from 1 to 20 carbon atoms and R.sup.3 is a hydrocarbyl group having 1 to 10 carbon atoms or an alkylene carboxylate group having formula R.sup.4COOH, where R.sup.4 is a saturated or unsaturated hydrocarbylene having from 1 to 10 carbon atoms. Methods of drilling wells include operating a drill in a wellbore in the presence of drilling fluid compositions.

Drilling fluid compositions include invert emulsion fluids having an oleaginous phase, an aqueous phase, and an emulsifier composition that includes an ethoxylated alcohol compound and a polyaminated fatty acid compound. The ethoxylated alcohol compound has the formula R.sup.1(OCH.sub.2CH.sub.2).sub.nOH, where R.sup.1 is a hydrocarbyl group having from 8 to 22 carbon atoms and n is from 1 to 8. The ethoxylated alcohol compound has a Hydrophilic-Lipophilic Balance (HLB) of less than or equal to 6. The polyaminated fatty acid compound has the formula R.sup.2CONHCH.sub.2CH.sub.2N(COR.sup.2)CH.sub.2CH.sub.2NHCOR.sup.3, where R.sup.2 is a hydrocarbyl group having from 1 to 20 carbon atoms and R.sup.3 is a hydrocarbyl group having 1 to 10 carbon atoms or an alkylene carboxylate group having formula R.sup.4COOH, where R.sup.4 is a saturated or unsaturated hydrocarbylene having from 1 to 10 carbon atoms. Methods of drilling wells include operating a drill in a wellbore in the presence of drilling fluid compositions.

Drilling fluid compositions include a base fluid, at least one additive chosen from an emulsifier, weighting material, fluid-loss additive, viscosifier, or alkali compound, and from 0.1 wt. % to 1 wt. %, based on total weight of the drilling fluid composition, of an ethoxylated alcohol compound having the formula R(OCH.sub.2CH.sub.2).sub.7OH, in which R is a saturated or unsaturated, linear or branched hydrocarbyl group having from 8 to 20 carbon atoms. The base fluid may be an aqueous base fluid. Methods for drilling a subterranean well include operating a drill in a wellbore in the presence of a drilling fluid composition including the base fluid, the additive, and the ethoxylated alcohol compound.

Drilling fluid compositions include a base fluid, at least one additive chosen from an emulsifier, weighting material, fluid-loss additive, viscosifier, or alkali compound, and from 0.1 wt. % to 1 wt. %, based on total weight of the drilling fluid composition, of an ethoxylated alcohol compound having the formula R(OCH.sub.2CH.sub.2).sub.7OH, in which R is a saturated or unsaturated, linear or branched hydrocarbyl group having from 8 to 20 carbon atoms. The base fluid may be an aqueous base fluid. Methods for drilling a subterranean well include operating a drill in a wellbore in the presence of a drilling fluid composition including the base fluid, the additive, and the ethoxylated alcohol compound.

Anti-bit balling drilling fluids and methods of making and using drilling fluids are provided. The anti-bit balling drilling fluid contains water, a clay-based component, and at least one of a surfactant having the formula: R(OC.sub.2H.sub.4).sub.xOH, where R is a hydrocarbyl group having from 10 to 20 carbon atoms and x is an integer from 1 and 10, or a polyethylene glycol having the formula: H(OCH.sub.2CH.sub.2).sub.nOH, where n is an integer from 1 to 50. Methods of making and using these drilling fluids are also provided.

Anti-bit balling drilling fluids and methods of making and using drilling fluids are provided. The anti-bit balling drilling fluid contains water, a clay-based component, and at least one of a surfactant having the formula: R(OC.sub.2H.sub.4).sub.xOH, where R is a hydrocarbyl group having from 10 to 20 carbon atoms and x is an integer from 1 and 10, or a polyethylene glycol having the formula: H(OCH.sub.2CH.sub.2).sub.nOH, where n is an integer from 1 to 50. Methods of making and using these drilling fluids are also provided.

Anti-bit balling drilling fluids and methods of making and using drilling fluids are provided. The anti-bit balling drilling fluid contains water, a clay-based component, and at least one of a surfactant having the formula: R(OC.sub.2H.sub.4).sub.xOH, where R is a hydrocarbyl group having from 10 to 20 carbon atoms and x is an integer from 1 and 10, or a polyethylene glycol having the formula: H(OCH.sub.2CH.sub.2).sub.nOH, where n is an integer from 1 to 50. Methods of making and using these drilling fluids are also provided.

Anti-bit balling drilling fluids and methods of making and using drilling fluids are provided. The anti-bit balling drilling fluid contains water, a clay-based component, and at least one of a surfactant having the formula: R(OC.sub.2H.sub.4).sub.xOH, where R is a hydrocarbyl group having from 10 to 20 carbon atoms and x is an integer from 1 and 10, or a polyethylene glycol having the formula: H(OCH.sub.2CH.sub.2).sub.nOH, where n is an integer from 1 to 50. Methods of making and using these drilling fluids are also provided.