US 7,678,281 B2 · Method of reclaiming brine solutions using an organic chelant

Abstract

A method of reclaiming a well completion brine solution containing metal impurities by introducing to the brine solution an organic chelant of the formula: and may be either a neutral compound, a corresponding salt, or a corresponding quaternary salt, wherein: D is F-A (Y3)u(Y4)v; R is independently selected from Cp or CpC(O); Cp is a C1-C36, preferably a C8-C36, hydrocarbyl group, optionally substituted with one or more substituents selected the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups; each A is independently selected from —N and —P; Y1 is independently selected from J, —[(F)-A(J)]w Y6 and R; J, R1, Y2, Y3, Y4, Y5 and Y6 are independently selected from the group consisting of —H, R, —(F)nCO2Z and —(CH2)nPO(OZ)2; each F is independently selected from a C1-C12 hydrocarbyl group, optionally substituted with one or more substituents selected from the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups; Z is —H, a balanced organic counterion or a balanced counterion of an alkali or alkaline earth metal, Zn or NH4+ or a mixture thereof; m is 0 to 7; n is 1 to 7; r+s+t is 1 or 2; u+v is 1 or 2; and w is 0 to 7 provided when m is 0, no more than one of R1, Y1, Y2 and Y5 can be —H. An organic chelant may be introduced to the brine containing the metal impurities. The brine may contain an oxidizer. Further, the pH of the brine being reclaimed or the brine reclaimed may be adjusted by the addition of a pH adjustment agent.

Claims32

Dependent claims

A method of reclaiming a well completion brine comprising the steps of:

(a.) mixing the brine containing metal impurities with an oxidizer and at least one organic chelant for a time sufficient for the chelant to complex a metal and form a complexed metal precipitate, the organic chelant being a neutral compound or a corresponding salt of the formula:
wherein:
D is F-A (Y3 )u (Y4)v;
R is independently selected from Cp or CpC(O);
Cp is a C1 -C36 hydrocarbyl group, optionally substituted with one or more substituents selected the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups;
each A is independently selected from —N and —P;
Y1 is independently selected from J, —[(F)-A(J)]w Y6 and R;
J, R1, Y2 , Y3, Y4, Y5 and Y6 are independently selected from the group consisting of —H, R, —(F)nCO2Z and —(CH2)nPO(OZ)2;
each F is independently selected from a C1-C12 hydrocarbyl group, optionally substituted with one or more substituents selected from the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups;
Z is —H, a balanced organic counterion or a balanced counterion of an alkali or alkaline earth metal, Zn or NH4+ or a mixture thereof;
m is 0 to 7;
n is 1 to 7;
r+s+t is 1 or 2;
u+v is 1 or 2;
and
w is 0 to 7
provided when m is 0, no more than one of R1, Y1, Y2 and Y5 can be —H;
and
(b) removing the complexed metal precipitate from the brine
wherein the metal impurities contain iron and further wherein the complexed metal precipitate contains iron.

17 more elements

A method of reclaiming a well completion brine comprising mixing the brine containing metal impurities with at least one organic chelant for a time sufficient for the chelant to complex a metal and form a complexed metal precipitate and then removing the complexed metal precipitate from the brine to render a reclaimed brine, wherein the method further comprises adjusting the pH of the well completion brine and/or the reclaimed brine and further wherein the organic chelant is either a neutral compound or a corresponding salt of the formula:

wherein:
D is F-A (Y3)u (Y4)v;
R is independently selected from Cp or CpC(O);
Cp is a C1-C36 hydrocarbyl group, optionally substituted with one or more substituents selected the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups;
each A is independently selected from —N and —P;
Y1 is independently selected from J, —[(F)A (J)]w Y6 and R;
J, R1, Y2, Y3, Y4, Y5 and Y6 are independently selected from the group consisting of —H, R, —(F)nCO2Z and —(CH2)nPO(OZ)2;
each F is independently selected from a C1-C12 hydrocarbyl group, optionally substituted with one or more substituents selected from the group consisting of halogen, hydroxyl, sulfate, CH2CO2Z or —(CH2)nPO(OZ)2 groups;
Z is —H, a balanced organic counterion or a balanced counterion of an alkali or alkaline earth metal, Zn or NH4+ or a mixture thereof;
m is 0 to 7;
n is 1 to 7;
r+s+t is 1 or 2;
u+v is 1 or 2;
and
w is 0 to 7
provided when m is 0, no more than one of R1, Y1, Y2 and Y5 can be —H
wherein the metal impurities contain iron and further wherein the complexed metal precipitate contain iron.

14 more elements

Dependencies are inferred from the claim text.

Method of reclaiming brine solutions using an organic chelant

Life of this patent

Method of reclaiming brine solutions using an organic chelant

Life of this patent

Abstract

Claims32