EP3642297A1 - Fluide de forage et procédé de tunnellisation - Google Patents

Fluide de forage et procédé de tunnellisation

Info

Publication number
EP3642297A1
EP3642297A1 EP18819655.4A EP18819655A EP3642297A1 EP 3642297 A1 EP3642297 A1 EP 3642297A1 EP 18819655 A EP18819655 A EP 18819655A EP 3642297 A1 EP3642297 A1 EP 3642297A1
Authority
EP
European Patent Office
Prior art keywords
drilling fluid
drilling
mixed metal
bentonite
viscosity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP18819655.4A
Other languages
German (de)
English (en)
Other versions
EP3642297A4 (fr
Inventor
Carl Keith Smith
Josh GAWRYLUK
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Canadian Energy Services LP
Original Assignee
Canadian Energy Services LP
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Canadian Energy Services LP filed Critical Canadian Energy Services LP
Publication of EP3642297A1 publication Critical patent/EP3642297A1/fr
Publication of EP3642297A4 publication Critical patent/EP3642297A4/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
    • C09K8/02—Well-drilling compositions
    • C09K8/04—Aqueous well-drilling compositions
    • C09K8/14—Clay-containing compositions
    • C09K8/16—Clay-containing compositions characterised by the inorganic compounds other than clay
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
    • E21B21/003—Means for stopping loss of drilling fluid
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
    • E21D9/04—Driving tunnels or galleries through loose materials; Apparatus therefor not otherwise provided for

Definitions

  • This invention relates to drilling fluids and methods boring a subterranean tunnel through a formation, such as for pipelines.
  • a drill bit, mud motor and other drilling assembly components including reamers are used to bore a tunnel below a river, a lake, an ocean strait, a road or other obstacle.
  • a drilling fluid with specific physical properties is circulated down through a drill pipe, out through the bit and up the annulus in order to clean the tunnel. In some situations the fluid is pumped out the drill pipe and suspends drilled cuttings that must be pushed out the other end of the tunnel.
  • Pipeline tunnel boring is an operation that is required to safely place pipelines, such as those used for transmitting oil, gas, water, sewage, below rivers, ocean straits, roads, lakes and other such natural and man-made obstacles in an efficient and environmentally safe manner.
  • Pipeline boring involves the use of a rotary drilling rig or sometimes two rigs with one rig on either side of a river for example.
  • the drilling process typically involves a drill bit with a directional motor assembly that is capable of steering the drilling down, then to horizontal and then up to the surface on the other side of the obstacle (for example the opposite side of a river).
  • the process of tunnel boring has a number of unique technical challenges.
  • the size of the tunnels varies but the most challenging tunnels have diameters in the range of 30 to 80 inches, for example about 50 to 60 inches with one common tunnel size being 1371 .6 mm (54").
  • the length of the tunnel from its surface entry point to its exit can be in the order of kilometers. They are often drilled in very young formations that can contain a very large fraction of easily hydratable clays or loose tills. In addition, the true vertical depths are often 100m or less.
  • the fracture gradients of the formations drilled can be low and it is possible to induce fractures to surface (underneath a river for example) with the result of whole losses of the circulating drilling fluid. It is possible that such fractures will communicate with the surface with the result that the surface becomes contaminated with the drilling fluid. For example, it is a significant concern that an environmentally sensitive area such as a river becomes contaminated with drilling fluid. It is possible that such contamination results in the problematic accumulation of the fluid in the environment.
  • the process of drilling can include drilling a smaller diameter pilot hole and then deploying an expandable reamer that scrapes the tunnel borehole walls and increases the diameter on one or more subsequent passes to the required size.
  • a method for drilling a tunnel through a formation comprising: preparing a mixed metal-viscosified drilling fluid including bentonite, a mixed metal viscosifier and controlling pH to 8.5 to 9.5 to permit a reaction between the bentonite and the mixed metal viscosifier; adding at least one of: (i) calcium sulfate and (ii) a potassium salt; and pumping the drilling fluid while drilling the tunnel with the pH lowered to 7 - 9.
  • a method for drilling a tunnel through a formation comprising: providing a mixed metal-viscosified drilling fluid; circulating the drilling fluid through the tunnel while drilling into the formation; monitoring the drilling fluid for a condition of drilling indicative of a problematic increase in viscosity of the drilling fluid; adding to the drilling fluid at least 1 % w/v potassium salt; and adding a non-toxic anionic thinner to the drilling fluid to adjust the viscosity of the drilling fluid.
  • a method for drilling a tunnel through a formation comprising: providing a mixed metal-viscosified drilling fluid; circulating the drilling fluid through the tunnel while drilling into the formation; monitoring the drilling fluid for a condition of drilling indicative of a problematic increase in viscosity of the drilling fluid; adding calcium sulfate to the drilling fluid to bring the concentration to at least 0.05% w/v calcium sulfate in the drilling fluid; and adding a non-toxic anionic thinner to the drilling fluid to adjust the viscosity of the drilling fluid.
  • a mixed metal-viscosified drilling fluid comprising: water; 15 to 45 kg/m3 bentonite; a mixed metal viscosifier at a weight ratio of 1 :3 to 1 :30, viscosifier to bentonite; at least 0.05% w/v calcium sulfate and/or at least 1 % w/v potassium salt; a polyacrylate anionic thinner; and a base to maintain the pH above 7.0.
  • a method for boring a tunnel including circulating an MMH-based drilling fluid with a non-toxic anionic additive.
  • the fluid is able to incorporate a large amount of reactive clays and a non-toxic anionic thinner reduces the viscosity in a controlled manner and is environmentally acceptable.
  • Aqueous - All fluids must be water based -
  • the base fluid may be sea water.
  • Mixed metal-viscosified drilling fluids include a mixed metal viscosifier, which is an inorganic particle based on magnesium/aluminum oxides and/or hydroxides. They are commonly known as mixed metal hydroxides and sometimes referred to as mixed metal oxide (MMO), mixed metal hydroxide (MMH) and combinations of mixed metal oxide and hydroxide (MMOH).
  • MMO mixed metal oxide
  • MMH mixed metal hydroxide
  • MMOH mixed metal oxide and hydroxide
  • MMH mixed metal layered hydroxide compound of the following empirical formula:
  • M' can represent any divalent metal cation of the Groups IA, IIA, VIIB, VIII, IB or MB of the Periodic Table
  • preferred divalent cations are Mg, Ca, Mn, Fe, Co, Ni, Cu, and Zn, and more preferred are Mg and Ca.
  • M" is a trivalent metal cation selected from Groups IA or VIII, but preferred are Al, Ga and Fe, and more preferred is Al.
  • these anions and negative-valence radicals include carbonates, amines, amides, chlorides, oxides, and the like. Preferred therefor are carbonates, oxides, chlorides and amides.
  • One mixed metal viscosifier of interest is the mixed metal hydroxide of the formula [Mgo.7Alo.3(OH)2](OH)o.3.
  • Another mixed metal viscosifier of interest is AI/Mg(OH) 4 .7Clo.3.
  • Mixed metal viscosifiers are commercially available such as from BASF Oilfield Polymers Inc. under the trademark PolyvisTM.
  • Polyvis IITM is a mixed metal hydroxide viscosifier.
  • Calcium sulfate and/or potassium salts including one or more of potassium sulfate, potassium chloride, potassium acetate and potassium formate may substantially maintain the rheology of mixed metal-viscosified drilling fluids when drilling with coal contaminants.
  • Such salts may add a benefit of shale swelling inhibition, possibly as a result of the presence of the potassium ion or calcium ion from the salt.
  • the salts are believed to protect the electrostatic relationship between the clay and the viscosifier.
  • MMH-based fluids are excellent hole cleaning fluids and in many ways are well suited for applications such as tunneling.
  • the fluids are pH dependent and require a basic pH to maintain appropriate rheology.
  • the MMH additive interacts strongly with the young high reactive clays that can be incorporated through a tunneling process. Clay incorporation can result in a dramatic and sometimes uncontrollable increase in fluid viscosity.
  • methods have been found for tunneling with MMH-based fluids and, in fact, these fluids have proven to be valuable to address holes where there is the risk of significant fluid loss such as is encountered in tunneling for pipeline installs.
  • a method for tunneling employs a drilling fluid that is water-based, pH controlled and includes bentonite, a mixed metal viscosifier and at least one of: (i) calcium sulfate and/or (ii) potassium salts including one or more of potassium sulfate, potassium chloride, potassium acetate and potassium formate.
  • Calcium sulfate (gypsum) has proven to be quite useful.
  • concentrations of calcium sulfate greater than 0.05% may be effective in the mixed metal- viscosified drilling fluid. While amounts of up to 5% or more may be used, generally concentrations of 0.05% - 1 .0% (weight by volume) calcium sulfate and, for example, 0.05 - 0.5% salt (weight by volume) or 0.1 - 0.5% concentrations have been found to be both effective for stabilizing the drilling fluid against adverse rheological changes and advantageous in terms of economics. These fluids have been employed for drilling coals.
  • calcium sulfate in the drilling fluid may be useful. It is believed that the calcium sulfate reaches saturation at about 2 to 3 kg/m3, (0.2 to 0.3% (w/v)), but excess amounts may be added without an adverse effect and in fact may create a buffer of salt to maintain activity, provided the fluid remains a liquid which can be circulated through the tunnel borehole. Generally, based on a cost/benefit analysis, an upper limit of 1 .0% or more likely 0.5% is considered sound.
  • potassium sulfate and/or potassium chloride have shown the best results with potassium sulfate being particularly preferred.
  • a wide range of potassium salt concentrations such as concentrations greater than 1 % (weight by volume), may be effective in the mixed metal-viscosified drilling fluid. Generally concentrations of 1 - 10% (weight by volume) salt and, for example, 1 - 5% salt (weight by volume) concentrations have been found to be both effective for stabilizing the drilling fluid against adverse rheological changes due to coal contamination and advantageous in terms of economics.
  • the amount of salt added to the drilling fluid may be determined by the amount of coal to be drilled and/or by the shale reactivity.
  • Bentonite which is a form of clay, is commonly used in drilling fluids and its use will be well understood by those skilled in the art.
  • various types of bentonite are useful such as polymer-treated bentonite, untreated bentonite.
  • An untreated bentonite may be particularly useful.
  • Such a bentonite may be known commercially as untreated bentonite with a high content of sodium montmorillonite, natural bentonite or untreated Wyoming bentonite.
  • mixed metal-viscosified drilling fluids are made up with low concentrations of bentonite such as, for example, about 15 to 45 kg/m3 or 20 to 40 kg/m3 bentonite in fresh water.
  • Sea water-based mixed metal-viscosified drilling fluids can accommodate more bentonite, as will be appreciated.
  • many bentonite based (non-mixed metal) drilling fluids can contain many multiples more (i.e. two to four times) bentonite than in a mixed metal-viscosified drilling fluid, it can be appreciated that the viscosity generated using such low concentrations of bentonite for mixed metal-viscosified drilling fluids might be insufficient for hole cleaning.
  • mixed metal oxide, mixed metal hydroxide or mixed metal oxide and hydroxide at a weight ratio of 1 :3 to 1 :20, 1 :7 to 1 : 12 or 1 :8 to 1 : 10.5 to the added bentonite produces a stable fluid.
  • contact with clays in the formation may drive the actual clay concentration up considerably.
  • the rheology of mixed metal-viscosified drilling fluids is sensitive to increases in clay content, as may occur when drilling young, sedimentary formations, which are the common formations bored during tunnel boring.
  • mixed metal- viscosified drilling fluid systems can only operate within a relatively narrow range of active clay concentrations.
  • the method includes preparing a drilling fluid wherein MMH is at a weight ratio of 1 :3 to 1 :20 to the added bentonite. This may include making up the drilling fluid with slightly less bentonite than previously used, such as a weight ratio of 1 :3 to 1 :12 or 1 :7 to 1 :9:5 MMH : added bentonite.
  • the drilling fluid will also include the salt: calcium sulfate or potassium salts.
  • the method can include continuing to pump the drilling fluid with the MMH : total clay (for example as determined by MBT) being up to 1 :30, for example, in the range of 1 :20 - 1 :30.
  • MMH total clay
  • This method includes drilling into young reactive clays and a portion of the total clay arising from the entrainment of young reactive clays.
  • the drilling fluid's total clay is in excess of 100kg/m3.
  • further amounts of the salt may be added to maintain the salt concentrations noted above.
  • MMH may be added in limited quantities.
  • it may not be necessary to add further bentonite as its concentration will be maintained by entrained clays. This offers a considerable cost savings on chemicals and is environmentally advantageous, since any chemical load on the environment is significantly reduced.
  • the MMH-viscosified fluids are considered pH sensitive.
  • prior methods raised the pH to greater than 10.
  • the current method includes mixing the bentonite, MMH and calcium sulfate or potassium salt and, in order to trigger the reaction between the MMH and the bentonite, bringing the pH to 8.5 to 9.5 by addition of caustic soda, caustic potash, potassium carbonate, lime and/or soda ash.
  • the drilling fluid can be pumped with the pH lowered to between pH 7 and 9 without a problematic loss in viscosity.
  • Caustic soda, caustic potash, potassium carbonate, lime and/or soda ash may be added to control the pH in the range of 7-9. If environmental toxicity is a concern, pH control may use lime.
  • the higher MBTs noted above can be more readily achieved. It is believed that the pH 7-9 reduces the density of anionic charge around the clay platelets and attenuates the interaction between cationic clay platelet faces and the overall anionic edges.
  • a mixed metal-viscosified drilling fluid may include an aqueous mixture of about 20 to 30 kg/m3 bentonite, a mixed metal moiety in a quantity of about 1 :7 to 1 : 10 MMO, MMH or MMOH to bentonite, pH controlled to pH 8.5-9.5 and 1 to 5% potassium salt and/or 0.05 to 1 .0% calcium sulphate. After the gel forms, the pH may be reduced to pH 7-9.
  • Additives for fluid loss control, lost circulation, etc. may be added to the drilling fluid mixture, as desired.
  • Non or minor-ionic additives may be most useful. Some examples may include starch for fluid loss reduction, organophillic lost circulation materials (LCM), etc. Simple testing may verify the compatibility of any particular additive with the drilling fluid.
  • the bentonite may first be hydrated in water. Then the mixed metal moiety is added and pH is adjusted. The potassium/calcium salt can be added to the aqueous mixture of bentonite and mixed metal at any time. Additives such as LCM, fluid loss control agents, etc. can also be added when appropriate, as will be appreciated.
  • the drilling fluid may be circulated through the drill string, drill bit and tunnel bore annulus while drilling. Circulation of the drilling fluid may continue even when drilling is stopped in order to condition the well, prevent string sticking, etc.
  • the yield point of the drilling fluid may be maintained above 10Pa to provide advantageous effects.
  • the mixed metal-viscosified drilling fluids described herein are useful for boring into various types of formations. Even when contacting coal or clay, such fluids retain their advantageous properties such as relatively high yield points, high low end rheology and high and fragile gel strengths. Such properties are advantageous for use in boring tunnels, whether vertical, directional or horizontal due to superior hole cleaning capabilities and because these fluids mitigate against whole mud fluid losses to formations whether via formation fractures or high permeability sections.
  • the tunnel will generally be drilled to a depth of less than 100m, the tunnel can be at any depth, any orientation and through any rock type, such as for example, through gravels, clay, carbonates, sandstones, shales, coal, oil shales, etc.
  • the formation can be one known to contain clay and/or coal or otherwise.
  • salts such as for example calcium sulfate
  • the use of such a fluid mitigates against whole fluid loss into the coal formation, which are typically highly fractured due to the unique rheological properties of the fluid.
  • the present method is suitable for drilling with clay loading in excess of what was previously thought possible.
  • incorporating very high concentrations of clay may risk problematic rheology and may stress pumping systems.
  • drilling with the present drilling fluid through active, young clay zones, with unavoidable incorporation of clay to excessive MBTs, may increase fluid rheology, such that the drilling fluid may become substantially un-usable (i.e. unpumpable).
  • a method for boring a tunnel through a formation includes: adding a non-toxic anionic thinner to the drilling fluid to adjust the viscosity of the drilling fluid.
  • One method for example includes: providing a mixed metal-viscosified drilling fluid; circulating the drilling fluid through the bore hole while boring into the formation; adding calcium sulfate to the drilling fluid to bring the concentration to 0.05 to 1 .0% w/v calcium sulfate; and adding a non-toxic anionic thinner to the drilling fluid to adjust the viscosity of the drilling fluid.
  • At least 1 % w/v potassium salt may be employed in the method in place of or in addition to the calcium salt.
  • a potassium salt or the calcium sulfate the use of anionic thinners would reduce the viscosity of the mixed metal-viscosified drilling fluid to nearly that of water. Without the use of an anionic thinner, the fluid may become unworkably viscous when drilling into clay.
  • the mixed metal-viscosified drilling fluid can be according to that described above: an aqueous mixture of a mixed metal viscosifier, as described above, and bentonite, as described above, with pH control between 7- 9.5, possibly with the method as described above, and a non-toxic anionic thinner.
  • the drilling fluid including the anionic thinner can be employed for the entire tunnel boring project or in response to identifying a condition of problematic rheological change such as one indicative of a problematic increase in the clay content of the drilling fluid.
  • the step of identifying may consider the location of the hole being drilling, for example using drilling measurements, relative to the location of known clay deposits, for example using formation logs or offset coring. If it is determined that the hole being drilled may, or is going to, pass through problematic clay deposits, then this can be noted according to the method and the step of adding an anionic thinner may be initiated when or before the drilling process begins in the clay deposit.
  • the salt may be added to the drilling fluid at any time.
  • the salt may be added during the initial production of the drilling fluid, such that the salt is present in the system throughout the drilling operation or the salt may be added only after identifying a condition of drilling indicative of an increase in the clay content of the drilling fluid.
  • the salt may be added after problematic clay contamination occurs, it is recommended to pre-treat the system for best results.
  • the initial hole can be drilled down to approximately the level of the first clay deposit using any drilling fluid of interest, including for example, prior art mixed metal-viscosified drilling fluids.
  • the drilling fluid may be changed over to one including a mixed metal-viscosified drilling fluid containing an amount of the salt and the anionic thinner.
  • the borehole may be drilled down to and into a clay deposit using a mixed metal-viscosified drilling fluid containing greater than 1 % w/v potassium salt and/or greater than 0.05% calcium sulfate and then the anionic thinner may be added.
  • the entire tunnel substantially from surface which may include drilling from surface or from below the overburden, may be drilled using a drilling fluid including a mixed metal viscosifier, bentonite, the appropriate amount of the salt and the non-toxic anionic thinner.
  • a drilling fluid including a mixed metal viscosifier, bentonite, the appropriate amount of the salt and the non-toxic anionic thinner.
  • the anionic thinner could be added at any time.
  • the entire tunnel is bored using the fluid with the non-toxic anionic thinner.
  • the anionic thinner may be added to the drilling fluid after identifying a condition indicating a problem with the fluid such as a risk of fluid loss or that the drilling fluid has an increased clay concentration.
  • the anionic thinner may be added when it is expected that the tunnel borehole is to be drilled into a clay deposit.
  • fluid rheology can be monitored, the viscosity of the fluid can be measured or the concentration of clay in the drilling fluid can be monitored directly to identify a condition indicative of an increase in the clay concentration.
  • the MBT procedure can be employed to quantitatively analyze the clay content of the drilling fluid.
  • the fluid viscosity may be monitored as by determining the funnel viscosity or more accurately with a device such as a rheometer, such as a Fann 35 rheometer. When the viscosity increases beyond an acceptable level, a condition indicative of an increase in clay content is identified. Once the clay concentration or the viscosity indicates a problematic condition, the thinner may be added. In one embodiment, for example, thinner is added to address problematic rheological profiles.
  • the condition indicating that there is a problematic condition may vary depending on the equipment and operator's preferences.
  • the fluid must be pumpable and the anionic thinner may be added to ensure that the drilling fluid remains pumpable.
  • the thinner may be added as follows: a) when funnel viscosity reaches 70 seconds/litre;
  • Anionic thinners of interest are anionic chemicals or minerals including coal fines, lignite, lignite resin, humalite, poly-anionic cellulose, tetra potassium pyrophosphate (TKPP), sodium acid pyrophosphate, tetra sodium pyrophosphate, polyacrylic acid, polyacrylates, polyacrylate co-polymers or xanthan gum that are non-toxic to environmental ecosystems, considered by regulators to be compatible with inclusion in ground water at the concentrations used.
  • Polyacrylate-based thinners such as polyacrylic acid, polyacrylates, polyacrylate co-polymers are of particular interest as they are considered environmentally safe and have a high activity.
  • Suitable polyacrylate polymers typically have a molecular weight of less than 10,000 and in most cases less than 1 ,000 g/mol.
  • Some anionic thinners such as caustic and tannin including sulfonated tannin (which is for example, available as DescoTM) are not appropriate, as they are considered toxic to some ecosystems.
  • the non-toxic anionic thinner may be added to the circulating drilling fluid. If the thinner is free flowing liquid or powder, it may be added directly.
  • the thinner is added in an amount sufficient to bring the fluid parameters to acceptable levels.
  • the yield point of the drilling fluid should be maintained above 10Pa to provide advantageous effects.
  • thinners used to achieve this above-noted rheological profile will vary depending on the activity of the thinner, the amount of clay contamination, etc.
  • a useful concentration range for polyacrylate-based thinners is 0.1 to 10 L/m3 in the drilling fluid. Concentrations are dependent on desired final viscosity.
  • the present drilling fluid may continue to be used for the remainder of the tunnel boring operation or other drilling fluids may be used. However, if clay can continue to become entrained in the drilling fluid, for example where a clay deposit remains open to contact by the drilling fluid, it may be useful to continue using the present drilling fluid until drilling is complete or the possibility of clay contamination is eliminated. If desired, the drilling fluid returning to the mud tanks at surface may be monitored to determine the concentration of salt and thinner therein, and/or other parameters indicative of problematic clay content, to ensure that fluid characteristics are maintained. For example, any one or more of the bentonite, mixed metal viscosifier, base, salt or anion thinner may be added during drilling to adjust the drilling fluid parameters.
  • an amount of mixed metal viscosifier may be added to the fluid during the course of a drilling operation where reactive formations are drilled and drill cuttings become incorporated into, and change the rheology of, the drilling fluid. In such a case, the addition of an amount of mixed metal viscosifier can cause the viscosity of the fluid to increase.
  • an initial amount of an anionic thinner and further amounts of that or another anionic thinner may be added to the fluid during the course of a drilling operation where reactive clay formations are drilled and clay becomes incorporated into, and changes the rheology of, the drilling fluid. In such a case, the addition of an amount of thinner can cause the viscosity of the fluid to decrease.
  • additives may be employed in the drilling fluid such as starch for fluid loss reduction, organophillic lost circulation materials (LCM), etc.
  • Simple testing may verify the compatibility of any particular additive with the drilling fluid.
  • the bentonite may first be hydrated in water. Then the mixed metal moiety is added and pH is adjusted. The salt can be added to the aqueous mixture of bentonite and mixed metal with or before the thinner. Additives such as LCM, fluid loss control agents, etc. can also be added when appropriate, as will be appreciated.
  • a representative MMH viscosified base fluid was tested for controlled thinning with the test thinning agent short chain polyacrylate
  • Base fluid comprised of:
  • the Base fluid was mixed and measured to which was added a concentrated aqueous (40 % w/w) low molecular weight (LMW) polyacrylate polymer.
  • the polyacrylate solution comprises of polymer that typically has a molecular weight of less than 1000 g/mol.
  • MMH mixed metal hydroxide viscosifier
  • gypsum gypsum and lime
  • MBT is a measure of the amount of reactive bentonitic clays in the drilling fluid and is the sum of the intentionally added natural bentonite plus a contribution of reactive drilled clay cuttings incorporated into the drilling fluid.
  • the drilling fluid was successfully used to ream the tunnel from 508mm to 762mm through sand and clay formations.
  • the pH was allowed to drop from 8.0 to 7.5 while maintaining advantageous rheology properties.
  • MMW mixed metal hydroxide viscosifier
  • pH 8.5
  • 762 mm tunnel reaming operations Made up the bottom hole assembly (BHA) with reamer and commenced pull reaming operations from the exit side with 1 .28 m3/min pump rates.
  • a problematic increase in viscosity occurred once 762 mm reaming operations commenced.
  • the pull ream operations commenced using a drilling fluid with a funnel viscosity of 125 s/L. The viscosity had been raised to this level on the previous reamed section to deal with hole cleaning and lost circulation issues.
  • the funnel viscosity increased by 39m to 175 s/L.
  • the drilling fluid was successfully used to ream the 555 m tunnel to 762mm through sand and clay formations with full control of the rheology properties. Successfully pulled 508 mm diameter pipe through the tunnel.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Dispersion Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Earth Drilling (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)

Abstract

Un procédé de forage d'un tunnel à travers une formation doit résoudre des problèmes environnementaux. Un procédé de tunnellisation comprend les étapes consistant à : préparer un fluide de forage rendu visqueux par un métal mixte, comprenant de la bentonite, un améliorant de viscosité à base de métal mixte et réguler le pH de 8,5 à 9,5 pour permettre une réaction entre la bentonite et l'améliorant de viscosité à base de métal mixte ; ajouter au moins l'un parmi : (i) le sulfate de calcium et (ii) un sel de potassium ; et pomper le fluide de forage pendant le forage du tunnel avec le pH abaissé à 7 – 9. La quantité d'améliorant de viscosité à base de métal mixte utilisée peut être limitée de telle sorte que le rapport pondéral de l'améliorant de viscosité à base de métal mixte à MBT atteigne jusqu'à 1:30. Dans le cas d'une augmentation problématique de la viscosité, un diluant anionique non toxique peut être ajouté au fluide de forage. Un tel diluant anionique est un polyacrylate.
EP18819655.4A 2017-06-23 2018-06-22 Fluide de forage et procédé de tunnellisation Withdrawn EP3642297A4 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201762524361P 2017-06-23 2017-06-23
PCT/CA2018/050777 WO2018232532A1 (fr) 2017-06-23 2018-06-22 Fluide de forage et procédé de tunnellisation

Publications (2)

Publication Number Publication Date
EP3642297A1 true EP3642297A1 (fr) 2020-04-29
EP3642297A4 EP3642297A4 (fr) 2021-03-17

Family

ID=64735441

Family Applications (1)

Application Number Title Priority Date Filing Date
EP18819655.4A Withdrawn EP3642297A4 (fr) 2017-06-23 2018-06-22 Fluide de forage et procédé de tunnellisation

Country Status (5)

Country Link
EP (1) EP3642297A4 (fr)
AU (3) AU2018286661B2 (fr)
CA (2) CA3061085C (fr)
MA (1) MA49467A (fr)
WO (1) WO2018232532A1 (fr)

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5260269A (en) * 1989-10-12 1993-11-09 Shell Oil Company Method of drilling with shale stabilizing mud system comprising polycyclicpolyetherpolyol
MY112090A (en) * 1992-10-22 2001-04-30 Shell Int Research Method for drilling and cementing a well
US9670394B2 (en) * 2007-03-02 2017-06-06 Canadian Energy Services L.P. Drilling fluid and method for drilling a wellbore
CN101675139A (zh) * 2007-03-02 2010-03-17 技术之星能源服务公司 钻井液和在含煤地层中钻井的方法
EP2609169B1 (fr) * 2010-08-26 2017-03-15 Tech-Star Fluid Systems Inc. Fluide de forage et procédé pour le forage dans des formations contenant du charbon
MX359568B (es) * 2013-01-08 2018-10-01 Canadian Energy Services Lp Fluido de perforacion y metodo para perforar un pozo.
CN104650823B (zh) * 2015-02-11 2016-02-03 中国石油大学(北京) 高渗特高渗储层的保护剂组合物和钻井液及其应用

Also Published As

Publication number Publication date
AU2021201364A1 (en) 2021-03-18
CA3061085A1 (fr) 2018-12-27
MA49467A (fr) 2021-03-17
AU2018286661A1 (en) 2020-02-13
CA3030574C (fr) 2019-12-31
CA3061085C (fr) 2020-09-08
AU2021201374A1 (en) 2021-03-18
AU2018286661B2 (en) 2020-12-03
CA3030574A1 (fr) 2018-12-27
WO2018232532A1 (fr) 2018-12-27
AU2021201374B2 (en) 2023-03-23
EP3642297A4 (fr) 2021-03-17
AU2021201364B2 (en) 2022-12-22

Similar Documents

Publication Publication Date Title
US8017563B2 (en) Diverting compositions, fluid loss control pills, and breakers thereof
US10202532B2 (en) Drilling fluid and method for drilling a wellbore
CA2564566A1 (fr) Systeme de fluide de forage aqueux inhibiteur et procede de forage de sables et d'autres formations sensibles a l'eau
CA2978541C (fr) Agents ameliorant l'indice de viscosite et agents de regulation de filtration a utiliser dans des operations souterraines a temperature elevee
WO2021029876A1 (fr) Matériaux déshuilés à circulation perdue
US11753573B2 (en) Calcium carbonate lost circulation material morphologies for use in subterranean formation operations
WO2008112481A1 (fr) Agent d'inhibition d'hydratation de schiste argileux et procédé d'utilisation
CA2802048C (fr) Fluide de forage et procede pour forer un puits de forage
AU2021201374B2 (en) Drill fluid and method for tunneling
US11155742B2 (en) Drill fluid and method for tunneling
US11661542B2 (en) Stimuli responsive polymers for lost circulation applications
CA2898884A1 (fr) Procedes de valorisation de fluides de forage comprenant des argiles de basse et de haute qualite
AU2017445157B2 (en) Selective salt management for wellbore fluids using microgel particles
WO2020060525A1 (fr) Inhibiteurs de schistes polymères hydrosolubles

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20200123

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

RIN1 Information on inventor provided before grant (corrected)

Inventor name: SMITH, CARL KEITH

Inventor name: GAWRYLUK, JOSH

REG Reference to a national code

Ref country code: DE

Ref legal event code: R079

Free format text: PREVIOUS MAIN CLASS: C09K0008240000

Ipc: E21B0021000000

A4 Supplementary search report drawn up and despatched

Effective date: 20210211

RIC1 Information provided on ipc code assigned before grant

Ipc: C09K 8/16 20060101ALI20210205BHEP

Ipc: E21B 21/06 20060101ALI20210205BHEP

Ipc: E21D 9/13 20060101ALI20210205BHEP

Ipc: E21D 9/11 20060101ALI20210205BHEP

Ipc: E21B 21/00 20060101AFI20210205BHEP

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20230206

P01 Opt-out of the competence of the unified patent court (upc) registered

Effective date: 20230518

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20230617