SA111320771B1 - Drilling Fluid Additive - Google Patents

Abstract

The present invention relates to a drilling fluid additive 10 used for sealing holes and/or cracks in drilled (geological) formations to prevent or at least limit lost circulation comprising fibers and scales 11. The fibers may include long fibers 12 and/or Short fibers 13. The additive to the drilling fluid may also include 10 acid soluble granules 15.

Description

: Drilling fluid additive Full Description BACKGROUND: The present invention relates generally to drilling fluid additives and specifically to drilling fluid additives used in sealing holes and/or faults in drilled (geological) formations to prevent Or at least to determine the lost circulation of drilling fluid (the loss of mud pumped in the drilling process).

0 pits). In the form of gals the present invention relates to a drilling fluid additive used in sealing

Excavated formations are very porous/cracked (or fractured). :

Although the present invention will be described with special reference to sealing holes and cracks within drilled holes of cis gas wells, geothermal wells (la JU) or hot springs “geothermal wells” it will be recognized that it may be used to seal holes and cracks in any other wells2 .

0 Sale drills Jie oil wells; Ola and Hamat wells to depths of thousands of meters below the surface of the earth. These wells are drilled using a drill bit placed at the bottom of a well jill cborehole and connected to a drill pipe extending up the Yass to the surface. A drilling fluid such as drilling mud is pumped down the drill pipe to the drill bit and then rotated in reverse to the top annulus between the drill hole and the drill pipe to carry drill cuttings resulting from the Jad cutting to the bit

J Drilling on a formation drilled upwards to the surface by the drilling fluid. on the surface; 9s of drilling fluid to be recycled through the drill hole.

Various problems can occur while drilling these wells. A 'lost Lexie' circulation problem occurs when drilling fluid escapes from the drill hole through holes and cracks in the drilled formation rather than being returned up the annular space between the drill hole and the drill pipe. It can sometimes increase

Y is undesirable in the amount of torque required to rotate the drill pipe during its rotation. like that; The drill pipe can also experience excessive pulling resistance as it is moved up or down the drilled hole. Another problem associated with unstable boreholes is flaking (or

. Formation collapse (sloughing) that can occur during drilling through Jie formations (Jia) coal formations and blocking or differential sticking where the drill pipe becomes stuck (to the wall of the well) during drilling. All of these problems occur in a manner Normal when drilling gle oil and shale wells The occurrence of any of these problems can add millions of dollars to well blowout costs Moreover, if a well blowout occurs as a result of any of the above problems the blowout can be fatal People present near the eruption when it occurs. into the drilling fluid to form a 'daa' (or a 'pill') which is then pumped down-hole jill with cella. They can already cause additional damage if used in the production area of the excavated formation and if oi perforates the production area in a non-reversible manner. Adding non-biodegradable dla particles/parts may block the ve drilling fluid which can permeate into the formation may permanently clog the production area causing the blisters not to develop biodegradable organic addition products from rice husks _peanut shells and loose wood ( Conifers (softwood) An attempt to overcome the problem of permanent obstruction of the production area associated with non-biodegradable ve additives. however; It was found that some of these organic products have disabling conditions when used as drilling fluid additives due to their natural properties. A special organic additive to drilling fluid that is very effective in sealing holes and cracks in geological formations and is able to prevent or limit the loss of drilling fluid while drilling these formations. It is an additive to drilling fluid called Fracseal™ (Coarse) sale Yo The addendum, which contains a tuneful blend of 0L teak long fibers and short cotton fibers, is set forth in Australian Patent Publication Application No. 000010977154 the entire contents of which are incorporated into this disclosure for reference.

aa) that the drilling fluid additive named FRACSEAL™ (Coarse) is only effective in sealing fault holes in formations with a permeability of 2000-7001 mD. This is not appropriate. A Because it is known that Ble drilling losses aad occur when drilling very porous/fractured formations with permeability greater than 20 000 md cost oil companies approximately $TY 0 billion annually. Therefore, it is appropriate to obtain a drilling fluid additive that combines the advantages of the Ellis FRACSEAL™ (Coarse) drilling fluid additive that can seal formations with greater permeability than Save Milli Darcy. It is against this background that the present invention has been developed. 0 GENERAL DESCRIPTION OF THE INVENTION One of the aims of the present invention is to overcome cle or at least improve; deficiency or shortcomings of one or more of the prior technology mentioned above; or to provide the consumer with an advantageous or commercial choice. Other aims and features of the invention call will be evident from the following description; Taking into account the relevant fees and accompanying fees. where; For clarification and representation; A preferred By 10 embodiment of the invention is indicated. According to the appearance of the first aggregate Gy of the invention; An additive was supplied for drilling fluid that includes fibers and flakes in the manner of Janie c. The fibers include organic fibers. Preferably » fibers include biodegradable fibres. Y. “Junie” fibers include allll cellulose preferably .cellulose fibers; The fibers include crushed fibres. Preferably the fibers include calibrated fibers 51260. Preferably. GLI ranges in size from 1 to 010 microns. It is particularly preferred that the fibers range in size from © to 4800 microns. ve preferably; Fibers include long fibres. Long fibers preferably contain wood fibres. It is especially preferred that the long fibers comprise hardwood fibers in a preferably “ald” shape. The long fibers include type 2/60074/160/076 teak fibers. on

JU) Ja ALLY fibers may include teak fibers tectorasteciona grandis (common teak). Wood fibers may include milled and calibrated saw dust.

Thanks to the fact that the fibers include short fibers. Short fibers preferably include cotton fibers (gossypium/gossipium cotton plant).

Juma: Fibers include a mixture of long and short fibers. It is preferable that the ratio of long fibers to short fibers range between 790 long fibers and 7970 short fibers; to 7 60 long fibers and 0077 BUH short fibers.

preferably The peels include organic peels. Preferably » peels include biodegradable peels. 1 Preferably” the husks include cellulose husks. (Jamie) The flakes comprise ground flakes. “Preferably” the flakes comprise standardized flakes. Preferably. The flakes range in size from 100 to 750 080 microns. In a preferred form; the flakes range in size from 500 to 72 000 µm. In Preferred AT form » range

1 The scales are from 0.01 to 60010 microns.

Typically, Jade shells include shell flakes 001. In special preferred shape; The shells include peanut shell flakes

Preferably the fibers and husks are mixed together. It is especially desirable to combine the fibers and the husks together.

Preferably, the drilling fluid additive also contains soluble ALE granules. It is preferable that the soluble granules contain soluble granules 8010. It is especially preferable that the soluble granules contain calcium carbonate - (CaCO;) granules

Preferably the soluble granules range in size from 101 to 75 microns.

Yo Preferably the concentration of soluble granules in the drilling fluid additive ranges from 0 to Ve for example” in a drilling additive bag of capacity (May Yo (1),Y0) kg )» Soluble granules may range in weight from 7.5 lbs to 3.75 lbs (= 1.0 llama kg).

according to a second, overall appearance according to the invention; A pill comprising a drilling fluid and a drilling fluid additive is furnished according to the first aggregate appearance according to the invention. preferably The drilling fluid is a drilling fluid. For example; iL drilling fluid may be cele-based drilling fluid; oil-based drilling fluid; or synthetic based drilling fluid. 2 preferably; The ratio of drilling fluid to drilling fluid additive is such that there are 50 lbs (7.2? kg) Lyi of additive in each barrel of pellets. according to a third aggregate appearance according to the invention; A method for sealing the holes or cracks inside the borehole is provided. The method comprises the steps: providing a ball according to the second overall appearance according to the invention; and 01 circulating the pellets through the borehole so that an impermeable wall or filtration sediment is formed comprising a base material of fibers and flakes of the drilling fluid additive for the pellets on the surface of the bore wall. according to a fourth overall appearance according to the invention; Provide a borehole through which pellets have been rolled in accordance with the second overall appearance according to the invention; And the drill hole includes a basically impermeable wall or filter cake sediment on the surface of the wall of the drill hole and includes hardened drilling slag (the part of the ve drilling mud sticking to the walls of the cake (Li) as a base material for fibers and crusts sale in addition to the drilling fluid for the pellets BRIEF EXPLANATION OF THE DRAWINGS To better understand and practically implement the invention a preferred embodiment thereof will now be described by reference to the accompanying drawings, where: Drilling; Figure 1 : Depicting a barrel containing a lost circulation pill Drilling and boreholes; and ve Fig. : Gia is a flowchart showing the method of sealing holes and/or cracks in a borehole.

Detailed description with reference to Fig. 0 drilling fluid additive 01 according to the preferred embodiment documented of the invention contains a graded scales adaptive mixture; ORGANIC AND BIODEGRADABLE 11 OF LONG FIBER AND AY SHORT FIBER 2 Shells 11 are obtained by grinding and calibrating the size of peanut shells. We grind the peanut shells to 11 shell sizes ranging from 001 to 0001 microns. The fibers Gl 11 ALN are milled and sizing cotton (gossypium/gossipium-type) The short fibers are 1” teak fibers (tectora/tectona grandis type 0) milled and sizing. Short fibers VF are obtained by grinding and sizing teak sawdust Long fibers VY and short fibers VT are milled and calibrated to size from © to 806 micron Flakes 11 may be produced in addition to long fibers 11 and short fibers 11 0 using the same milling and/or size calibration equipment, eg may all be produced using the equipment and methods described in Australian Patent Publication No. 700099791549 which is fully incorporated into this disclosure for your reference. Ratio of flakes 11 long fibers OY and short fibers 11 in sale the addition of drilling fluid 01 so that the ratio of long fibers 11 to short fibers 11 ranges in the range of 778 GUT x long to 70 fibers Short; to 0.74 long fibers to 770 short fibers; the ratio of 11 husks to fibers STAY ranges from IY. husks to 780 fibres.” Ive scaled to 7700 fibers. Referring to the form oY, the sale addition of drilling fluid 01 is added to drilling fluid Vo, such as; For example JB drilling mud based on water or oil to form a drilling fluid loss pellet 1?. The ratio of sale Ye addition of drilling fluid 01 to drilling fluid is 71 in drilling fluid loss pellets VY preferably so that There shall be approximately 50 lbs (0.0 kg) of drilling fluid additive 01 in each barrel of YY pellets 1 7.

Referring to the two forms “and ?; during use; The drilling fluid 70 to which the sale addition of the drilling fluid 01 is added, which is called the ory pellets, is pumped to the bottom of the LT borehole specially; Drilling fluid Ye is pumped down drill pipe 1 ? to drill bit TY and then reverse-circulated to the top annular space VY between wall ;? For drill hole Te and drill pipe TY > In addition to the sale addendum 101 the drilling fluid Yo reversed to the top of the annulus vy includes drilling crumbs and other particles dad dda also. Increasing Glas overbalance pressure (i.e. the extent to which the hydrostatic pressure of drilling fluid 01 in the drill hole © is greater than the pressure of the formation in which the drill hole is being drilled (ad Ye) of drilling fluid 71 in the OY crusts 0" long fibers and short fibers 0" VF of additive 01 combined with flakes and other 0 solid particles in drilling fluid 70 to form a thin wall/sediment filtration pha TO © wall surface of the drilling hole .01 forming Long fibers 11 and short fibers sale 1 “base 97 (see Figure 1) in the yo wall cake hardened drilling slag (which is the section of the drilling mud adherent to the walls of (a) the crusts 11 are combined with a material Pile 7 long and short fibers to reduce voids between 1 long fibers 11 and short fibers 01 in the FY primer and to form or shape the sale YA sass (see Figure 1) reinforced in the hardened drilling slag Parietal V0 The crumbs and other solid micro-colloid particles in the drilling fluid Yo reinforce the base material TY by filling voids between the scales 11 long fibers OY and short fibers 11 making the wall hardened drilling slag FO not implemented. To impermeable wall-hardened gall slag is capable of bridging or sealing © a very porous/cracked formation with a permeability greater than 5001 md and thus capable of stopping drilling fluid 71 from entering the formation from borehole 70 and from being is lost. The above steps include a 0*0 method for sealing holes and/or cracks within the drill hole Ke in other preferred embodiments of drilling fluid additive 01 of the present invention; The vo 11 graded organic scales may range in size from 000 to 15006 microns. In certain preferred embodiments the drilling fluid additive sale 01 may also include particles/granules 0 of milled calcium carbonate ((0800). The granules of calcium carbonate 50 enable the use of additive 01 to seal the formations of Ji productive without damaging the formations.

Calcium carbonate 50 granules are milled to a size ranging from size 40 (775 microns) to size 001 (120 microns). The concentration of granular calcium carbonate fr in dale drilling fluid additive 01 ranges from 701 to replace Y,o J lbs to 1,725 lbs (1-1,72 kg) for sale bags. Addition BL Drill 01 Yo has a capacity of 1.1 lbs (kg). The inclusion of calibrated, calibrated ground calcium carbonate size sale 00 makes the addition of drilling fluid 01 particularly suitable for formation sealing of a product such that severe drilling fluid loss is excluded or at least reduced. The ale seepage/seal formed by Ve additive can be removed/released without damaging the formation area sealed by acid/acid treatment p80010/p201012108_of

Sle after removal/release fr acid calcium carbonate granules cu ki 01 addition 0 or more Jie seepage/sealing in this way; The formation area can produce more oil or gas than was originally intended. Laboratory tests of the additive for drilling fluid 01 according to the present invention using the modified filter press test according to the American Petroleum Institute modified API Filter Press Test With 10 aggregates 1-5 cm in size as filter media. These experiments showed the very effective sealing ability of drilling fluid additive .01 in particular; showed that the combined matrix YA of fibers 1, 1 and flakes 11 is capable of forming an essentially impermeable filtration precipitate or Sala that fills or covers the gaps between the aggregates. Whereas other FRACSEAL™ (Coarse) Jie (LCM) fluid loss additive is capable of lav sealing very effectively fractured formations with a success rate of less than 200, drilling fluid additive 01 is expected to be able to The invention of the invention effectively seals such formations with a success rate greater than JA results in the inclusion of granular calcium carbonate ?0 in drilling fluid additive 01 an acid soluble drilling fluid additive that can be used to exclude or at least reduce drilling fluid loss ve 10 in product configuration. Significantly (Ray) Modifying the drilling fluid additive 01 in this way Additive 01 eliminates or at least reduces the loss of drilling fluid without damaging the formation. This is compared to the available acid-soluble drilling fluid loss materials that tend to damage productive formations in order to reduce thus The amount of oil or gas that the formation can reduce.

It will be understood by those skilled in the art that alterations and modifications to the invention described in this disclosure will be apparent without departing from the scope and scope of the invention. Changes and modifications as made clear to those skilled in the art are within the scope and scope of the overall invention as set forth in this disclosure. Through the entire detection and protection elements; Unless the context otherwise requires, the word 8 'comprise' includes or changes comprises' Jie or Ald to comprising a specified integer or group of integers but does not exclude any other integer or group of integers. Through the entire detection and protection elements; unless the context requires otherwise; The term "substantially" or "about" will be understood as not defining to ded the defined range Ve in terms. It is well understood that if a previous technical bulletin is referred to; Such reference does not constitute an acknowledgment that the Prospectus forms part of the general common knowledge of technology in Australia or any other country.

Claims (1)

protection elements 1-1 Drilling fluid additive includes teak wood fibers (tectora/tectona Y) cotton fibers (gossypium/gossipium) flakes 1 and soluble granules dal) so that the fibers range from 1 to (See 00001) and the scales aaa range from 001 to 79000 microns” and the soluble granules range from 100° to 5/79 microns. sale -" 1 the addition of the drilling fluid additive according to claim 1 where the Y fibers include ground fibers sale = F 0 The drilling fluid additive in accordance with any of the foregoing claims; The fibers range in size from © to Are microns. : sale —¢ 0 drilling fluid additive in accordance with any of the foregoing claims; Y where teak fibers include (ra) teak type (tectora/tectona) common teak fibers - Common Teak (tectora/tectona grandis) 1 sale —o 1 drilling fluid additive in accordance with any of the foregoing claims; Y, where the wood fibers include saw dust cada ground and calibrated to size. sale -+0 the drilling fluid additive in accordance with any of the foregoing claims; 7 where the flakes include organic flakes sale = y 0 The drilling fluid additive in accordance with any of the foregoing claims; 1 where the flakes include biodegradable flakes sale -” + 0 The drilling fluid additive in accordance with any of the foregoing claims; Y where the flakes include cellulose flakes 1" 0 4- Drilling fluid additive according to any of the previous protection elements; Y where scales include milled scales. - 0 01-01 drilling fluid additive according to any of the elements of protection The previous protection; Y, where the scales range in size from On to Y Dass microns. A=) according to any of the drilling fluid additive protection elements sale -11 1. to F microns 1 Where the flakes range in size from Y sale -1 ! The addition of the drilling fluid additive according to any of the previous claims; Y where the flakes include -nut shell flakes Jedi where OY according to the drilling fluid additive claim VY -peanut shell flakes Y =V 0 Drilling fluid additive according to any of the previous claims; v where soluble granules include acid soluble granules -1# 0 drilling fluid additive according to claim VE where v acid soluble granules include calcium carbonate granules calcium carbonate (CaCOs;). .granules 7-11 0 drilling fluid additive in accordance with any of the foregoing claims; Y, where the concentration of the soluble granules in the drilling fluid additive ranges from 701 to Je v -17 0 A pellet that includes a drilling fluid and a drilling fluid additive according to any of the previous protections. VA pill according to claim OY where the drilling fluid is a drilling fluid. -19 0 pill according to claim VA wherein the drilling fluid is selected from the drilling fluid group which 0 includes a water-based drilling fluid; oil-based drilling fluid; or synthetic based drilling fluid. -*0 0 pill according to any of the claims 117 to 90; wherein the ratio of drilling fluid to drilling fluid additive is such that there are 50 lbs (0,0YY kg) of additive r of the drilling fluid in each barrel of pellets. -71 1 method for sealing holes or cracks inside da ill The method includes the steps: 7 supplying pellets according to any of the protection elements winding to ¢Y. and r circulating the pellets through the drilled hole so that a wall is formed Impermeable or sediment filter cake 1 contains a primer for fibers and scales sale in addition to the drilling fluid for the pellets on the surface of the adi] las © drilling. 0 77- a borehole through which pellets were rotated in accordance with any of the claims 11 to Yo Jey y the borehole essentially impermeable wall or a leaching sediment on the wall surface of the borehole 3 borehole; The hardened drilling slag cake (the section of drilling mud adhered to the walls of Ad 1) includes a base material for the fibers and flakes of the drilling fluid additive for pellets. no