Abstract: A method for delivering a scale treatment agent to a hydrocarbon producing system. The method includes the steps of contacting the system with a foam comprising the scale treatment agent, and shutting the scale treatment agent in the system for at least 0.5 hour.

Abstract: The present invention provides a method for increasing the retention of a scale inhibitor within a hydrocarbon producing system (e.g. a subterranean formation), said method comprising contacting said system with a polymer formed from a diallyl ammonium salt and with said scale inhibitor, wherein said polymer formed from a diallyl ammonium salt has a molecular weight of greater than 50,000 (e.g. a molecular weight of 55,000 to 2,000,000).

Abstract: The present invention provides a method for increasing the retention of a scale inhibitor within a hydrocarbon producing system (e.g. a subterranean formation), said method comprising contacting said system with a polymer foamed from a diallyl ammonium salt and with said scale inhibitor, wherein said polymer formed from a diallyl ammonium salt has a molecular weight of greater than 50,000 (e.g. a molecular weight of 55,000 to 2,000,000).

Abstract: The invention provides a method for the treatment of a hydrocarbon well which method comprises administering, down said well, polymeric particles having covalently bound to a polymeric component thereof a well treatment chemical or a precursor thereof, wherein the particles contain covalent bonds scissile in an aqueous environment to release or expose said chemical or precursor.

Abstract: The present invention provides a method for delivering a scale treatment agent to a hydrocarbon producing system, said method comprising: contacting said system with a foam comprising said scale treatment agent; and shutting said scale treatment agentin said system for at least 0.5 hour.

Abstract: The invention provides a method for the treatment of a hydrocarbon well which method comprises administering, down said well, polymeric particles having covalently bound to a polymeric component thereof a well treatment chemical or a precursor thereof, wherein the particles contain covalent bonds scissile in an aqueous environment to release or expose said chemical or precursor.

Abstract: According to the invention, a fully viscosified acid diversion system for hydrofluoric acid has been developed. The viscosifying agent comprises a xanthan polymer or a derivative thereof. A method of acidizing a portion of a subterranean formation is provided, the method comprising the steps of: (A) forming a viscosified treatment fluid comprising: (i) water; (ii) hydrogen fluoride or a controlled-release source of hydrogen fluoride; and (iii) a gelling agent comprising a xanthan polymer or derivative thereof; and (B) introducing the viscosified treatment fluid into the portion of the subterranean formation. A breaking agent can be used to achieve a controlled gel break time under downhole conditions. Other additives can also be included in the treatment fluid.

Abstract: The invention provides a method for the treatment of a hydrocarbon well which method comprises administering, down said well, polymeric particles having covalently bound to a polymeric component thereof a well treatment chemical or a precursor thereof, wherein the particles contain covalent bonds scissile in an aqueous environment to release or expose said chemical or precursor.

Abstract: The invention provides a method for the treatment of a hydrocarbon well which method comprises administering, down the well, inverse suspension polymerized polymer particles having immobilized therein a well treatment chemical or a precursor or generator thereof.

Abstract: A method for the treatment of a hydrocarbon well comprising administering down the well polymeric particles impregnated with a well treatment chemical or precursor or generator thereof. The particles have a pore volume of at least 20%, and are prepared by a process which comprises preparing an aqueous dispersion of polymer particles containing from 0.05 to 10 times by volume, based on the polymer, of one or more specific first material(s) adding a partly water-soluble second material having a water-solubility of at least ten times that of first material(s) under conditions which prevent or hinder transport of first material(s) through the aqueous phase, whereby second material diffuses into the polymer particles swelled with first material(s) and increases the volume of said particles by from 20 to 1000 times, based on the polymer.

Abstract: Gelatin capsules containing oil field chemicals, preferably weighted with a heavy metal compound, are made more stable under certain conditions by the incorporation of a strong chelating agent. The microcapsules can provide an extended treatment period since many materials that would damage the microcapsules are controlled by the chelating agent.

Abstract: The invention provides a method for the treatment of a hydrocarbon well which method comprises administering down said well polymeric particles having covalently bound to a polymeric component thereof a well treatment chemical or a precursor thereof, said particles containing covalent bonds scissile in an aqueous environment to release or expose said chemical or precursor.

Abstract: The invention provides a method for the treatment of a hydrocarbon well which method comprises administering down said well polymeric particles impregnated with a well treatment chemical or precursor or generator thereof (e.g. a scale inhibitor), said particles having a pore volume of at least 20%, and being prepared by a process which comprises preparing in a first step an aqueous dispersion of polymer particles containing from 0.