Aluminate-thickened well treating fluid and method of use

Claim 2

A PROCESS FOR TEMPORARILY PLUGGING A SUBTERRANEAN RESERVIOR, WHICH PROCESS COMPRISES: COMPOUNDING A METAL HYDROXIDE-THICKNED AQUEOUS FLUID CONTAINING ENOUGH WATER-SOLUBLE SALT OF AN AMPHOTERIC METAL AND ENOUGH WATERSOLUBLE BASE TO FORM A VISCOSITYINCREASING PROPORTION OF GELATINOUS HYDRATED METAL OXIDE AND PROVIDE A PH THAT IS RELATIVELY NON-CORROSIVE TO FERROUS METAL; ADJUSTING THE SPECIFIC GRAVITY AND FLUID LOSS PREVENTION PROPERTIES OF THE FLUID RELATIVE TO THE DEPTH AND FLUID PRESSURE OF THE RESERVOIR TO THE EXTENT REQUIRED TO PROVIDE A HYDROSTATIC HEAD THAT AT LEAST COUNTER-BALANCES THE RESERVOIR FLUID PRESSURE AND A FLUID LOSS PREVENTION PROPERTY THAT SUBSTANTIALLY PREVENTS LOSS INTO THE RESERVOIR; AND FLOWING THE SO-ADJUSTED FLUID INTO THE WELL TO FORM A COLUMN OF FLUID EXTENDING FROM A NEAR-SURFACE LOCATION TO THE DEPTH OF THE RESERVOIR.

Claim 3

The process of claim 1 in which a substantially solids-free fluid is formed by adjusting the concentrations of water soluble salts and base that are dissolved in said metal hydroxide-thickened aqueous fluid to effect said adjustment of specific gravity and fluid loss prevention properties.

Claim 4

The process of claim 1 in which particles of a solid material that is soluble in a relatively strongly acidic or basic aqueous liquid are suspended in the metal hydroxide-thickened aqueous fluid.

Claim 5

The process of claim 1 in which a relatively slow reacting material that reacts to yield a water-soluble acidic product that reduces the pH of an aqueous liquid is dissolved in the metal hydroxide-thickened fluid.

Claim 6

The process of claim 1 in which the metal hydroxide-thickened aqueous fluid is compounded by dissolving at least one each of a water soluble aluminum salt, an alkali metal hydroxide and an alkaline earth metal chloride in an aqueous liquid.

Claim 7

The process of claim 1 in which the metal hydroxide-thickened aqueous fluid is compounded by dissolving at least one each of a water soluble aluminum salt, an alkali metal hydroxide and an alkaline earth metal bromide in an aqueous liquid.

Claim 8

A FLUID COMPOSITION THAT TEMPORARILY PLUGS A SUBTERRANEAN RESERVOIR WHEN IT IS POSITIONED SO THAT IT FORMS A COLUMN OF FLUID EXTENDING BETWEEN THE RESERVOIR AND A NEAR SURFACE LOCATION, WHICH COMPOSITION COMPRISES: A METAL HYDROXIDE-THICKNED AQUEOUS FLUID THAT CONTAINS ENOUGH WATER-SOLUBLE SALT OF AN AMPHOTERIC METAL AND ENOUGH WATER-SOLUBLE BASE TO PROVIDE, WITHIN SAID AQUEOUS FLUID, BOTH A VISCOSITY-INCREASING PROPORTION OF GELATINOUS HYDRATED METAL OXIDE AND A PH THAT IS RELATIVELY NON-CORROSIVE TO FERROUS METAL; AND WITHIN SAID AQUEOUS FLUID, A COMBINATION OF SPECIFIC GRAVITY AND FLUID LOSS PREVENTION PROPERTIES THAT ARE CORRELATED RELATIVE TO THE DEPTH AND FLUID PRESSURE OF SAID RESERVOIR TO PROVIDE A HYDROSTATIC HEAD THAT AT LEAST COUNTERBALANCES THE RESERVOIR FLUID PRESSURE AND A FLUID LOSS PREVENTION PROPERTY THAT SUBSTANTIALLY PREVENTS FLUID LOSS INTO THE RESERVOIR WHEN THE AQUEOUS FLUID IS POSITIONED SO THAT IT FORMS A COLUMN OF FLUID EXTENDING FROM THE RESERVOIR TO A NEAR SURFACE LOCATION.

Claim 9

A FLUID COMPOSITION THAT TEMPORARILY PLUGS A SUBTERRANEAN RESERVOIR WHEN IT IS POSITIONED SO THAT IT FORMS A COLUMN OF FLUID EXTENDING BETWEEN THE RESERVOIR AND A NEAR SURFACE LOCATION, WHICH COMPOSITION COMPRISES: A METAL HYDROXIDE-THICKNED AQUEOUS FLUID THAT CONTAINS ENOUGH WATER-SOLUBLE SALT OF AN AMPHOTERIC METAL AND ENOUGH WATER-SOLUBLE BASE TO PROVIDE, WITHIN SAID AQUEOUS FLUID, BOTH A VISCOSITY-INCREASING PROPORTION OF GELATINOUS HYDRATED METAL OXIDE AND A PH THAT IS RELATIVELY NON-CORROSIVE TO FERROUS METAL; AND WITHIN SAID AQUEOUS FLUID, A COMBINATION OF SPECIFIC GRAVITY AND FLUID LOSS PREVENTION PROPERTIES THAT ARE CORRELATED RELATIVE TO THE DEPTH AND FLUID PRESSURE OF SAID RESERVOIR TO PROVIDE A HYDROSTATIC HEAD THAT AT LEAST COUNTERBALANCES THE RESERVOIR FLUID PRESSURE AND A FLUID LOSS PREVENTION PROPERTY THAT SUBSTANTIALLY PREVENTS FLUID LOSS INTO THE RESERVOIR WHEN THE AQUEOUS FLUID IS POSITIONED SO THAT IT FORMS A COLUMN OF FLUID EXTENDING FROM THE RESERVOIR TO A NEAR SURFACE LOCATION.

Claim 10

The composition of claim 7 in which there are suspended particles of a solid material that is soluble in a relatively strongly acidic or basic aqueous liquid.

Claim 11

The composition of claim 7 in which a relatively slow reacting material that reacts to yield a water-soluble acidic product that reduces the pH of an aqueous liquid is dissolved in the metal hydroxide-thickened fluid.

Claim 12

The composition of claim 7 in which said salt and base are respectively an aluminum salt and an alkali metal hydroxide.

Claim 13

The composition of claim 7 in which there is dissolved an alkaline earth metal salt of one, but not both, of such chloride and bromides.

Claim 14

A process for temporarily plugging a subterranean reservoir, which process comprises: compounding a metal hydroxide-thickened aqUeous fluid containing enough water-soluble salt of an amphoteric metal and enough water-soluble base to form a viscosity-increasing proportion of gelatinous hydrated metal oxide and provide a pH that is relatively non-corrosive to ferrous metal; adjusting the specific gravity and fluid loss prevention properties of the fluid relative to the depth and fluid pressure of the reservoir to the extent required to provide a hydrostatic head that at least counter-balances the reservoir fluid pressure and a fluid loss prevention property that substantially prevents loss into the reservoir; and flowing the so-adjusted fluid into the well to form a reservoir contacting portion of a column of fluid extending from a near surface location to the depth of the reservoir.

Claim 15

A process for temporarily plugging a subterranean reservoir, which process comprises: compounding a metal hydroxide-thickened aqUeous fluid containing enough water-soluble salt of an amphoteric metal and enough water-soluble base to form a viscosity-increasing proportion of gelatinous hydrated metal oxide and provide a pH that is relatively non-corrosive to ferrous metal; adjusting the specific gravity and fluid loss prevention properties of the fluid relative to the depth and fluid pressure of the reservoir to the extent required to provide a hydrostatic head that at least counter-balances the reservoir fluid pressure and a fluid loss prevention property that substantially prevents loss into the reservoir; and flowing the so-adjusted fluid into the well to form a reservoir contacting portion of a column of fluid extending from a near surface location to the depth of the reservoir.