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US 11,198,812 B2Granted
Use of sequestering agent in GLDA-based treatments for siliceous formations
AssigneeBaker Hughes Holdings LLC
InventorsAndrea Nino-Penaloza, D.V. Satyanarayana Gupta, Sandra L. Berry, Harold G. Hudson, Elizabeth McCartney
Life of this patent
Estimating the term…
Abstract
Sandstone formations of oil and gas and geothermal wells may be successfully stimulated with a fluid containing GLDA or salt and HF or a HF-generating component and an organophosphonate component. The organophosphonate acts as a sequestering agent and reduces the amount of metal fluoride precipitates produced.
Claims20
A method of increasing the permeability of a siliceous subterranean formation comprising:
- (a) introducing into a well penetrating a siliceous subterranean formation an acidic fluid containing (i) from about 5 to about 50 weight percent of a glutamic-N,N-diacetic acid, salt or mixture thereof;
- (ii) from about 0.25 to 20 weight percent of a HF or a HF-generating component;
- and (iii) between from about 0.25 to about 50 weight percent of an organophosphonate compound, wherein the ratio of glutamic-N,N-diacetic acid or salt to HF concentration in the fluid is from 5:1 to 10:0.1
- and wherein either the fluid contains ammonium bifluoride or ammonium fluoride or a combination thereof as the HF-generating component or the organophosphonate of the fluid is of the formula:
- wherein R1, R2 and R3 are independently selected from hydrogen, alkyl, aryl, phosphonates, phosphates, acyl, amine, hydroxy and carboxyl groups and R4 and R5 are independently selected from hydrogen, sodium, potassium, ammonium or an organic radical;
- (b) dissolving siliceous materials of the formation and generating monovalent ions, divalent ions or a combination thereof;
- and
- (c) forming a complex of the organophosphonate and monovalent ions, divalent ions or a combination thereof after introduction of the acidic fluid into the well.
5 more elements
A method of stimulating production in a siliceous subterranean formation of an oil, gas or geothermal well comprising:
- (a) introducing into a well penetrating a siliceous subterranean formation an acidic fluid comprising (i) from about 5 to about 50 weight percent of a glutamic-N,N-diacetic acid or salt or a mixture thereof;
- (ii) from about 0.25 to 20 weight percent of ammonium bifluoride or ammonium fluoride or a combination thereof as a HF-generating compound;
- and (iii) between from about 0.25 to about 50 weight percent of an organophosphonate selected from the group consisting of 1-hydroxyethylidine-1,1-diphosphonic acid, diethylene triamine penta(methylene phosphonic acid) and aminotri (methylene phosphonic acid) and mixtures thereof, wherein the ratio of glutamic-N,N-diacetic acid or salt to HF concentration in the fluid is from 5:1 to 10:0.1;
- (b) reacting the glutamic-N,N-diacetic acid, salt or mixture thereof and the HF or HF-generating component with the siliceous subterranean formation and generating un-complexed monovalent ions, divalent ions or a combination thereof;
- and
- (c) forming a complex by sequestering the un-complexed monovalent ions, divalent ions or combination thereof with the organophosphonate;
- and
- (d) producing hydrocarbons from the siliceous formation.
5 more elements
A method of remediating a sandstone formation of an oil or gas or geothermal well by:
- (a) introducing into the well a buffered HF-acidizing fluid comprising:
- (i) from about 5 to about 50 weight percent of a glutamic-N,N-diacetic acid, salt or mixture thereof;
- (ii) from about 0.25 to 20 weight percent of HF or a HF generating component or a mixture thereof;
- (iii) from about 0.25 to about weight percent of an organophosphonate of the formula:
- wherein R1, R2 and R3 are independently selected from hydrogen, alkyl, aryl, phosphonates, phosphates, acyl, amine, hydroxy and carboxyl groups and R4 and R5 are independently selected from hydrogen, sodium, potassium, ammonium or an organic radical
- and wherein the ratio of glutamic-N,N-diacetic acid or salt to HF concentration in the fluid is from 5:1 to 10:0.1 and the pH of the acidizing fluid is between from about 1.9 to about 4.8;
- and
- (b) forming complexes of the organophosphonate with monovalent ions, divalent ions or a combination thereof after introduction of the acidizing fluid into the well;
- and
- (c) remediating the well by removing the formed complexes therefrom.
7 more elements
Dependencies are inferred from the claim text.