Mobil Oil Corporation

Charles S Yeh

Lloyd G Jones

E Thomas Strom

Paul Shu

William P Donlon

Larry L Cox

Christopher V Chow

A method for consolidating a subterranean formation to control the production of particulates therefrom. A specific consolidating solution comprised of an allyl monomer and an initiator is injected into the formation where it is allowed to set at an elevated temperature to harden and form a permeable, consolidated mass. The allyl monomer is an allyl ester selected from the group of diallyl orthophthalate, diallyl isophthalate, diallyl terephthalate, diallyl benzenephosphonate, diethylene glycol bis (allyl carbonate) and other known allyl monomers and the initiator is preferably a peroxy compound (e.g. benzoyl peroxide, diisopropyl peroxydicarbonate, etc.) or an azo compound (e.g. 4,4'-azobis(4-cyanovaleric acid). A diluent such as an alcohol (e.g. isopropyl alcohol or isobutyl alcohol) or a mutual solvent (e.g. ethylene glycol monobutyl ether, diacetin, triacetin, acetone, etc.) and a coupling agent (e.g. an organofunctional silane) may be added if needed.

Method for consolidating a subterranean formation

A method for plugging a zone of a subterranean formation to block flow therethrough. A specific plugging solution comprised of an allyl monomer and an initiator is injected into the zone where it is allowed to set at an elevated temperature to harden and form a flow-blocking solid. The allyl monomer is an allyl ester selected from the group of diallyl orthophthalate, diallyl isophthalate, diallyl terephthalate, diallyl benzenephosphonate, diethylene glycol bis(allyl carbonate) and other known allyl monomers and the initiator is preferably a peroxy compound (e.g. benzoyl peroxide, diisopropyl peroxydicarbonate, etc.) or an azo compound (e.g. 4,4'-azobis(4-cyanovaleric acid). A diluent such as an alcohol (e.g. isopropyl alcohol or isobutyl alcohol) or a mutual solvent (e.g. ethylene glycol monobutyl ether, diacetin, triacetin, acetone, etc.) and a coupling agent (e.g. an organofunctional silane) may be added if needed.

Method for treating formations to plug flow

A cement for forming a gravel pack in a washed-out interval is provided where a borehole penetrates an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole. After perforating the borehole's casing at a washed-out interval of the formation, sand is introduced into the interval. Afterwards, an aqueous silicate solution is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid is introduced into the interval. Thereafter, a water-miscible organic solvent containing an alkylpolysilicate is injected into the interval. A permeability retaining silica cement is formed in the interval thereby making a gravel pack. Injection of the aqueous silicate and organic solvent containing an alkylpolysilicate is continued until the interval has been consolidated by the silica cement to an extent sufficient to exclude sand and formation fines.

Sand control agent and process

A method for gravel packing perforations in a wellbore where an acid is directed into the perforations so as to dissolve formation fines in channels contained in said perforations. The acid is of a strength sufficient to dissolve said fines. After the fines are dissolved, a sand consolidation agent is introduced into the perforations before the channels can be filled with formation fines. The consolidation agent remains in the perforations for a time sufficient to form a cement in situ which cement has permeability retentive characteristics. The cement forms pores of a size sufficient to exclude formation fines from the wellbore. Thereafter, a substantially fines free hydrocarbonaceous fluid is produced from the wellbore.

Acidizing method for gravel packing wells

A method for forming a gravel pack in a washed-out interval is provided where a borehole penetrates an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole. After perforating the borehole's casing at a washed-out interval of the formation, sand is introduced into the interval. Afterwards, an aqueous silicate solution is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid is introduced into the interval. Thereafter, a water-miscible organic solvent containing an alkylpolysilicate is injected into the interval. A permeability retaining silica cement is formed in the interval thereby making a gravel pack. Injection of the aqueous silicate and organic solvent containing an alkylpolysilicate is continued until the interval has been consolidated by the silica cement to an extent sufficient to exclude sand and formation fines.

A method for producing substantially sand or fines free hydrocarbonaceous fluids from a wellbore which is initially gravel packed. Thereafter, an acid is directed into the wellbore so as to dissolve formation fines in channels contained in perforations communicating with a productive interval of the formation. The acid is of a strength sufficient to dissolve said fines. After the fines are dissolved, a sand consolidation agent is introduced into the perforations before the channels can be filled with formation fines. The consolidation agent remains in the perforations for a time sufficient to form a cement in situ which cement has permeability retentive characteristics. The cement forms pores of a size sufficient to exclude formation fines from the wellbore.

Apparatus for gravel packing a wellbore interval having shunt means (i.e. conduits) on the external surface of a sand screen which can selectively deliver a gravel slurry to different levels of the interval during operation. The shunt means is comprised of a variety of differently configured, perforated conduits and/or arrangements of these conduits.

Gravel packing of wells

A sand screen is positioned in a well adjacent an oil or gas reservoir to be produced. At least one conduit is in juxtaposition with the sand screen and has passageways at selected intervals to establish fluid communication between the conduit and the annulus of the well surrounding the sand screen. A gravel packing slurry is injected down the well to form a gravel pack in the annulus. Actuatable devices associated with the conduit passageways control fluid flow between the conduit and annulus so that if the gravel portion of the slurry forms a bridge in the annulus, thereby blocking slurry flow through the annulus, the slurry will be diverted from the annulus into the conduit through one or more of the passageways in the conduit above the bridge, downward through the conduit and out through one or more passageways in the conduit into the annulus below the bridge to continue the forming of the gravel pack in the annulus.

Apparatus for gravel packing wells

A method for gravel packing perforations against homogeneous or heterogeneous reservoir formations utilizing a shear-thickening or dilatant fluid as the carrier medium of gravel. Use of this fluid provides for rheological behavior which improves both transporting and packing efficiencies/uniformities.

Growing community of inventors

Plano, TX, United States of America

Charles S Yeh