FLC by Gilsonite
HPHT Gilsonite FLC aid stable to high temperature such as 400°F. The composition comprises a mixture of a uintaite such as natural asphalt in combination with solubilized lignite such as a causticized lignite and carbon black. The HPHT FLC aid also comprises a product made by the process of combining the uintaite such as natural bitumen solubilized lignite such as causticized lignite and carbon black with one another since in some instances the natural asphalt and lignite might interact with one another and change the nature of the starting compounds. Additionally, the introduction of the composition of matter of the present invention into a drilling fluid could also alter the foregoing compounds used in the composition, and for this reason the invention also comprises a product produced by the process of combining the various compounds for the manufacture of the composition as well as a product produced by introducing the composition into a drilling fluid.
The invention also comprises a process for the control of HPHT FLC in subterranean wells by adding the composition or product produced by the process of forming the composition into a subterranean well. An uintaite employed according to the present invention may comprise natural asphalt an asphaltic material or solidified hydrocarbon which may be found in Utah and Colorado, and may comprise one of the purest natural bitumen.
Natural asphalt FLC oil well drilling
Gilsonite manufactured by ATDM CO LTD, Tehran Iran, which provides a variety of Gilsonite “resins,” sometimes identified by their softening points (ring and ball). General purpose (GP) Gilsonite brand resin has a softening point of about 350° F., and Gilsonite HM has a softening point of about 380° F., whereas Gilsonite select 300 and select 325 have softening points of about 300° and Select 325 have softening points of about 300° F. and 325° F. respectively. The source vein that the Gilsonite comes from primarily determines the softening points of these natural uintaite. Reference to uintaite or Gilsonite resins as used in the written description and the claims includes these materials, especially as described in Kirk-Othmer Encyclopedia of Chemical Technology, 3rd Ed. Vol. 11, 198C, pp.802-806 incorporated herein by reference.
Iran fluid loss control additives
Gilsonite resins used in drilling fluids according to the present invention may come from an area near ghasreshirin, Kermanshah Iran and have a specific gravity of about 1.05 with a softening point ranging from 370° to 400° F. although lower softening point Gilsonite resins, i.e., those having a softening point of about 330° F., also finds use in the composition of the invention. Accordingly, the Gilsonite resins employed in the invention have a softening point ranging from about 300° F. to about 400° F., especially from about 330° F. to about 400° F. and preferably from about 370° to about 400° F. The Gilsonite resins have a low acid value, zero iodine number, and will dissolve or partially dissolve in aromatic and aliphatic hydrocarbons, respectively. Part of the process of preparing Gilsonite resins involves grinding so that approximately 99% pass through a 65-mesh Tyler screen with approximately 3% retained on a 100-mesh screen and 16% retained on a 200-mesh screen, non-cumulative.
The uintaite employed according to one aspect of the invention comprises Gilsonite HM having a softening point of about 380°. Additionally, two or three component blends of Gilsonite HM, Gilsonite select 300 and Select 325 also find use in the invention, especially the to component blends. Anywhere from about 30 to about 70% by weight of the first Gilsonite can be employed in the combination with anywhere from about 70% to about 30% by weight of the second or second and third Gilsonite and especially from about 65% to about 35% by weight of the first Gilsonite to about 35% to about 65% by weight of the second or second and third Gilsonite. When employing a third Gilsonite®, the weight ratio of the second to the third Gilsonite will vary from anywhere from about 1 to about 5 to about 5 to about 1 especially 1 to about 4 to about 4 to about 1 and preferably from about 1 to about 2 to about 2 to about 1. When the process of the invention employs a combination of Gilsonite, it is especially preferred that the major component comprises a Gilsonite having a softening point from about 370° F. to about 380° F., especially where the composition employs two component blends of Gilsonite®. In one embodiment, the two-component blend will amount to more than about 50% Gilsonite having a softening point from about 370° to about 380° F. The composition employs the uintaite or Gilsonite in an amount from about 10% to about 70% by weight, especially from about 20% to about 60% by weight and preferably from about 45% to about 55% by weight of the HPHT FLC aid of the present invention.