Earth boring – well treating – and oil field chemistry – Well treating – Contains organic component
Reexamination Certificate
1997-10-31
2001-04-17
Kelly, C. H. (Department: 1756)
Earth boring, well treating, and oil field chemistry
Well treating
Contains organic component
C507S204000, C166S292000, C166S295000
Reexamination Certificate
active
06218343
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to tubing/casing annulus plug additives, to tubing/casing annulus plug treatment fluids made therefrom, to methods of plugging a tubing/casing annulus in a well bore. In another aspect, the present invention relates to tubing/casing annulus plug additives comprising polymer and fibers or comminuted plant materials, to tubing/casing annulus plug treatment fluids made therefrom, to methods plugging a tubing/casing annulus in a well bore.
2. Description of the Related Art
Portland cement is commonly used in oil field applications such as oil well cement jobs. Portland cements can be tailor-made for the specific conditions of each well. A description of the state of the art in oil well cementing technology is given in Basic Cementing, Petroleum Publishing Co., 1977 (reprinted from a series of articles appearing in the Oil and Gas Journal) and Rike, J. L., et al, Squeeze Cementing: State of The Art, Journal of Petroleum Technology, (January 1982), pp. 37-45.
Formulation of the cement in the field is largely a product of trial and error by field personnel to meet irregularities in the cementing composition and the downhole environment. Cement quality control is difficult to achieve under such conditions. As a result, Portland cement can exhibit premature set-up, cracking, or shrinking upon curing. This feature of Portland cement limits its usefulness in wellbore treatments to repair leaks in wellbore casing or tubing by plugging the tubing/casing pair annulus. Use of other available methods to remedy leaking wellbore tubulars, including workovers and redrilling, can be extremely cumbersome and expensive.
U.S. Pat. No. 4,730,674, issued Mar. 15, 1988 to Burdge et al., noted that a wellbore treatment process was needed for preventing or repairing leaking tubulars which was both economically and operationally attractive. Burdge et al. further noted that a process was needed which effectively employed a plugging material having a broad range of highly controllable and predictable set-up times for ease of operation and design. Burdge et al. even further noted that a process was needed which employed a plugging material which was not as susceptible as Portland cement to shrinking and cracking when applied to a tubing/casing annulus in a wellbore.
In an effort to overcome the deficiencies of the prior art and to fulfill the perceived needs, U.S. Pat. No. 4,730,674 discloses the use of a water soluble carboxylate crosslinking polymer along with a chromic carboxylate complex crosslinking agent in the plugging of a tubing/casing annulus in a wellbore, and at column 2, lines 30-35, specifically teaches away from the use of solids in the plugging fluid injected into the wellbore.
Thus, while U.S. Pat. No. 5,377,760, issued Jan. 3, 1995 to Merrill discloses addition of fibers to an aqueous solution of partially hydrolyzed polyacrylamide polymer, with subsequent injection into the subterranean to improve conformance, the performance requirements of conformance improvement treatment polymers are so different from those of polymers for plugging an abandoned well, that such would not necessarily work for plugging tubing/casing annulus. Furthermore, Burdge et al. teach away from injection a solid containing polymer into the wellbore to plug a tubing/casing annulus.
Additionally, Merrill's conformance treatment method of mixing the fibers with the polymer solution followed by injection, requires a multiplicity of storage and mixing tanks, and a metering system which must be operated during the operation of the well. Specifically, a first tank will store a water and polymer solution, a second tank will store a water and cross-linking solution, and a third tank will be used to mix fibers with polymer solution from the first tank to create a polymer/fiber slurry. This polymer/fiber slurry is then metered from the third tank and combined with crosslinking solution metered from the second tank to the well bore.
Thus, in spite of the advancements in the prior art, there still need for further innovation in the tubing/casing annulus plug additives.
There is need for further innovation for tubing/casing annulus plug additives utilizing a water soluble polymer.
There is another need for a tubing/casing annulus plug additive which would allow for simplification of the mixing equipment.
These and other needs in the art will become apparent to those of skill in the art upon review of this specification, including its drawings and claims.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide for further innovation in tubing/casing annulus plug additives.
It is an another object of the present invention to provide for further innovation for tubing/casing annulus plug additives utilizing a water soluble polymer.
It is even another object of the present invention to provide for a tubing/casing annulus plug additive which would allow for simplification of the mixing equipment.
These and other objects of the present invention will become apparent to those of skill in the art upon review of this specification, including its drawings and claims.
According to one embodiment of the present invention there is provided a tubing/casing annulus plug additive comprising a dry mixture of water soluble crosslinkable polymer, a crosslinking agent, and a reinforcing material selected from among fibers and comminuted plant materials. In preferred embodiments, the polymer is an a carboxylate-containing polymer and the crosslinking agent is a chromic carboxylate complex. In other preferred embodiments, the reinforcing material may comprise hydrophobic fibers selected from among nylon, rayon, and hydrocarbon fibers, and/or hydrophilic fibers selected from among glass, cellulose, carbon, silicon, graphite, calcined petroleum coke, and cotton fibers. The comminuted plant material is selected from the group of comminuted plant materials of nut and seed shells or hulls of almond, brazil, cocoa bean, coconut, cotton, flax, grass, linseed, maize, millet, oat, peach, peanut, rice, rye, soybean, sunflower, walnut, and wheat; rice tips; rice straw; rice bran; crude pectate pulp; peat moss fibers; flax; cotton; cotton linters; wool; sugar cane; paper; bagasse; bamboo; corn stalks; sawdust; wood; bark; straw; cork; dehydrated vegetable matter; whole ground corn cobs; corn cob light density pith core; corn cob ground woody ring portion; corn cob chaff portion; cotton seed stems; flax stems; wheat stems; sunflower seed stems; soybean stems; maize stems; rye grass stems; millet stems; and mixtures thereof.
According to another embodiment of the present invention, there is provided a method of forming a tubing/casing annulus plug fluid. The method generally includes taking the above tubing/casing annulus plug additive and contacting it with water or other aqueous solution.
According to even another embodiment of the present invention, there is provided a method of preventing plugging a tubing/casing annulus. The method generally includes contacting the above described tubing/casing annulus plug additive with water or an aqueous solution to form a tubing/casing annulus plug fluid. The method then includes injecting the tubing/casing annulus plug fluid into the wellbore.
These and other embodiments of the present invention will become apparent to those of skill in the art upon review of this specification and claims.
REFERENCES:
patent: 2610149 (1952-09-01), VanDyke
patent: 2708973 (1955-05-01), Twining
patent: 2779417 (1957-01-01), Clark et al.
patent: 3208524 (1965-09-01), Horner et al.
patent: 3374834 (1968-03-01), Ramos et al.
patent: 3408296 (1968-10-01), Kuhn et al.
patent: 3462958 (1969-08-01), Patin et al.
patent: 3701384 (1972-10-01), Routson et al.
patent: 3766984 (1973-10-01), Nimerick
patent: 3845822 (1974-11-01), Clampitt et al.
patent: 3981363 (1976-09-01), Gall
patent: 4018286 (1977-04-01), Gall et al.
patent: 4039029 (1977-08-01), Gall
patent: 4183406 (1980-01-01), Lundberg et al.
patent: 4247403 (1981-01-01), Foley et al.
Bottom Line Industries, Inc.
Gilbreth J. M. (Mark)
Gilbreth & Associates P.C.
Kelly C. H.
LandOfFree
Additive for, treatment fluid for, and method of plugging a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Additive for, treatment fluid for, and method of plugging a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Additive for, treatment fluid for, and method of plugging a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2457060