A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt. % of a primary H.sub.2S scavenger, which is potassium permanganate, and an invert emulsion, which includes a continuous phase including a vegetable oil which is at least one selected from the group consisting of corn oil, soybean oil, rapeseed oil, canola oil, sunflower oil, safflower oil, peanut oil, and cottonseed oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

Provided is a method making it possible to ensure a gradual release of polymer chains within a liquid medium, the method comprising bringing the liquid medium into contact with specific solid objects formed by polymer chains soluble in the medium and carrying hydrophobic side groups ensuring physical crosslinking between the polymer chains within the solid objects. The released chains may in particular be used as inhibitors of the formation of inorganic or organic deposits (scale inhibitors) within a liquid medium, typically in the field of oil extraction.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt.% of a primary H.sub.2S scavenger which is potassium permanganate. The drilling fluid composition includes an invert emulsion includes a continuous phase including palm oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore in the subterranean geological formation thereby producing a formation fluid. The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid includes 0.05 to 1 wt. % of a rhamnolipid surfactant based on a total weight of the drilling fluid. The drilling fluid includes an invert emulsion including a continuous phase and a dispersive phase including water.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid including hydrogen sulfide (H.sub.2S). The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid composition includes 0.25 to 2 wt. % of a primary H.sub.2S scavenger which is potassium permanganate. The drilling fluid composition includes an invert emulsion which includes a continuous phase including mineral oil and a dispersive phase including water. The potassium permanganate present in the drilling fluid composition reacts with the H.sub.2S present in the formation fluid to produce a dispersion of manganese-containing particles which are at least one selected from the group consisting of manganese sulfide and manganese sulfate.

A method of drilling a subterranean geological formation is described. The method includes driving a drill bit to form a wellbore in the subterranean geological formation thereby producing a formation fluid. The method includes injecting a drilling fluid into the subterranean geological formation through the wellbore. The drilling fluid includes 1 to 3 wt. % of a weighting agent which includes hydrophobic metallic zinc nanoparticles including a metallic core and organic ligands present on a surface of the metallic core, based on a total weight of the drilling fluid. The drilling fluid includes an invert emulsion including a continuous phase and a dispersive phase including water.

An aqueous solution is disclosed including water, an acid, a nitrogen-containing compound, and a functionalizing agent (FA), which can be a ketone, diketone, aldehyde, dialdehyde, organic acid, and combinations thereof. An additional aqueous solution is disclosed including water, an acid, and an acid neutralizing agent which can be a reaction product of at least a portion of the nitrogen-containing compound and the functionalizing agent. Methods of treating a formation are also disclosed including treating a formation fluidly coupled to a wellbore with an oilfield treatment fluid comprising either or both of the aqueous solutions.

A method for the 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 location slightly beyond a predetermined location; inserting a perforating tool having an outside surface and a spearhead or breakdown acid composition into the wellbore, wherein said outside surface of said tool is pre-treated prior to downhole insertion with a grease containing a first corrosion inhibitor adapted to eliminate/minimize/reduce the corrosion inflicted upon it by the exposure of the acid for the duration of the fracking or stimulation and wherein said acidic composition comprises a second corrosion inhibitor which reacts with said first corrosion inhibitor to generate a corrosion protective layer onto said surface; 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 stimulation; removing the tool from the wellbore; and initiating the fracking of the perforated area using a stimulation fluid. Also disclosed is a corrosion inhibiting compound or composition for use with the acid composition.

The anionic cocogem surfactant of formula (I) for an oil production process of increased efficiency ##STR00001##
wherein each R1 and R2 is independently selected from hydrogen or C1-C18 straight or branched alkyl optionally substituted by OH; each R3 is independently selected from hydrogen; C1-C25 straight or branched alkyl or alkenyl optionally comprising inter-chain amido-group; aromatic group optionally substituted by C1-C25, preferably C5-C20, more preferably C5-C15 straight or branched alkyl, preferably selected from phenyl and diphenylether; or C10-C20 straight or branched alkenyl, alkadienyl or alkatrienyl; Z is C1-C18 straight or branched alkylene optionally substituted by one or two C1-C6 alkyl or preferably C3-C6 cycloalkyl, optionally comprising (EO).sub.n and/or (PO).sub.m groups, wherein EO is ethylene-oxide i.e. —CH.sub.2CH.sub.2O—, and PO is propylene-oxide, i.e. —CH(CH.sub.3)CH.sub.2O—, wherein n and m is independently an integer of from 0 to 30 and n+m is an integer of from 1 to 30; and/or [NH(R4)].sup.+ quaternary ammonium, wherein R4 is hydrogen, C1-C6 alkyl, preferably methyl or ethyl; R5 is hydrogen or C1-C6 alkyl, preferably methyl or ethyl; An is one or more groups selected from SO.sub.3.sup.−, Cl.sup.− or CO.sub.2.sup.−; i is an integer of 0 or 1; p is an integer of 2 or 3; j is an integer of 2 or 3.

Dual cation hydrate inhibitor compositions and methods of using such compositions to, for example, inhibit the formation of gas hydrate agglomerates are provided. In some embodiments, such methods include introducing a hydrate inhibitor composition into a fluid, wherein the hydrate inhibitor composition includes at least one compound having the structural formula: ##STR00001##
wherein each of R.sup.1, R.sup.2, and R.sup.3 is independently a C.sub.1 to C.sub.6 hydrocarbon chain, wherein R.sup.4 is selected from the group consisting of hydrogen and any C.sub.1 to C.sub.50 hydrocarbon chain, wherein each of R.sup.5 and R.sup.6 is independently selected from the group consisting of hydrogen and a C.sub.1 to C.sub.50 hydrocarbon chain, wherein X.sup.− and Y.sup.− are counter anions, and wherein each of a and b is independently an integer from 1 to 10.