U.S. patent application number 14/244365 was filed with the patent office on 2014-07-31 for drilling fluid and methods.
The applicant listed for this patent is CANADIAN ENERGY SERVICES L.P.. Invention is credited to CARL KEITH SMITH.
Application Number | 20140213489 14/244365 |
Document ID | / |
Family ID | 45096698 |
Filed Date | 2014-07-31 |
United States Patent
Application |
20140213489 |
Kind Code |
A1 |
SMITH; CARL KEITH |
July 31, 2014 |
DRILLING FLUID AND METHODS
Abstract
A drilling fluid comprising: a non-ionic surfactant including: a
branched alcohol ethoxylate and/or a capped alcohol ethoxylate; and
a detergent builder.
Inventors: |
SMITH; CARL KEITH; (Calgary,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CANADIAN ENERGY SERVICES L.P. |
Calgary |
|
CA |
|
|
Family ID: |
45096698 |
Appl. No.: |
14/244365 |
Filed: |
April 3, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13171273 |
Jun 28, 2011 |
8703658 |
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14244365 |
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12025164 |
Feb 4, 2008 |
7989399 |
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13171273 |
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60894121 |
Mar 9, 2007 |
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Current U.S.
Class: |
507/136 ;
507/138; 507/139 |
Current CPC
Class: |
C09K 8/524 20130101;
C09K 8/035 20130101; C09K 8/34 20130101; C09K 8/12 20130101; C09K
2208/34 20130101 |
Class at
Publication: |
507/136 ;
507/139; 507/138 |
International
Class: |
C09K 8/34 20060101
C09K008/34 |
Claims
1. A drilling fluid comprising: 0.01 to 0.5% by weight of (i) a
branched alcohol ethoxylate and/or (ii) a capped alcohol
ethoxylate; and 0.01% to 0.5% by weight of a detergent builder.
2. The drilling fluid of claim 1 further comprising a
viscosifier.
3. The drilling fluid of claim 1 wherein the branched alcohol
ethoxylate includes alkyl polyethylene glycol ethers based on
C10-Guerbet alcohol and ethylene oxide.
4. The drilling fluid of claim 1 wherein the capped alcohol
ethoxylate includes chlorine capped ethoxylated C10-14-ISO
alcohols.
5. The drilling fluid of claim 1 wherein the capped alcohol
ethoxylate is a chlorine capped ethoxylated C9-11 ISO, C10 rich
alcohols.
6. The drilling fluid of claim 1 wherein the detergent builder
includes a phosphate-type builder.
7. The drilling fluid of claim 6 wherein the detergent builder
includes a pyrophosphate-type builder.
8. The drilling fluid of claim 7 wherein the detergent builder is
TKPP.
9. The drilling fluid of claim 1 wherein the detergent builder
includes a silicate-type builder.
10. The drilling fluid of claim 1 further comprising a lubricant
including a plant-based oil.
11. The drilling fluid of claim 10 wherein the lubricant includes a
fatty acid methyl ester.
12. The drilling fluid of claim 10 wherein the lubricant includes
soybean oil.
13. The drilling fluid of claim 10 wherein the lubricant includes
canola oil.
14. The drilling fluid of claim 10 wherein the lubricant includes
vegetable oil.
15. The drilling fluid of claim 10 wherein the lubricant is
non-ionic and has a flash point greater than 148.degree. C.
16. The drilling fluid of claim 1 further comprising a
defoamer.
17. The drilling fluid of claim 16 wherein the defoamer is fatty
alcohol ethoxylate.
18. The drilling fluid of claim 1 wherein the branched alcohol
ethoxylate is an alkyl polyethylene glycol ether based on
C10-Guerbet alcohol and ethylene oxide; the detergent builder is
TKPP; and 0.01 to 0.5% by weight of a plant-based oil.
19.-55. (canceled)
Description
FIELD
[0001] The invention relates to fluids used for drilling and
completing oil wells and in particular those useful for deterring
tar/heavy oil accretion on metal surfaces.
BACKGROUND
[0002] The process of drilling a hole in the ground for the
extraction of a natural resource requires a fluid for removing
cuttings from the wellbore, controlling formation pressures and
maintaining hole stability. Drilling through oil sand formations
causes problematic accretion of tar on drilling apparatus. Bitumen
accretion on metal surfaces impairs drilling operations by blinding
shale shaker screens, plugging centrifuges and drill bits, torque
and drag increase and stuck pipe or casing. Standard drilling
practices through oil sand formations, which are generally
unconsolidated, can also lead to hole instability problems.
[0003] If these formations are drilled horizontally, torque and
drag between the formation and the drill string can limit both the
rate of drilling and the ultimate length of the horizontal section
that can be achieved.
[0004] Solvents, surfactants and viscosifiers have been used in
drilling fluids for drilling through heavy oil, including
bitumen-containing formations. In addition, or alternately,
drilling fluids have been chilled to deter accretion and enhance
hole stability.
SUMMARY
[0005] A drilling fluid and a method for drilling have been
invented.
[0006] In accordance with one aspect of the present invention,
there is provided an aqueous drilling fluid comprising: 0.01 to
0.5% by weight of a branched alcohol ethoxylate and/or a capped
alcohol ethoxylate; and 0.01% to 0.5% by weight of a detergent
builder.
[0007] In accordance with another aspect of the present invention,
there is provided a method for drilling a wellbore through a
formation, the method comprising: operating a drilling assembly to
drill a wellbore and circulating a drilling fluid through the
wellbore as it is drilled, the drilling fluid being water-based and
including: 0.01 to 0.5% by weight of a branched alcohol ethoxylate
and/or a capped alcohol ethoxylate; and a detergent builder.
[0008] It is to be understood that other aspects of the present
invention will become readily apparent to those skilled in the art
from the following detailed description, wherein various
embodiments of the invention are shown and described by way of
illustration. As will be realized, the invention is useful for
other and different embodiments and its several details are capable
of modification in various other respects, all without departing
from the spirit and scope of the present invention. Accordingly the
drawings and detailed description are to be regarded as
illustrative in nature and not as restrictive.
DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS
[0009] A drilling fluid and a method for drilling a wellbore has
been invented for use in formations bearing heavy oil, also called
bitumen or tar. The drilling fluid and method are useful to limit
and possibly remove tar accretion on metal surfaces, reduce torque
and drag and/or to maintain borehole stability, while working with
standard viscosifiers and other chemicals used in drilling fluids.
The drilling fluid and method may therefore be environmentally
responsible and economically viable.
[0010] A drilling fluid according to the present invention includes
a non-ionic surfactant including at least one of (i) a branched
alcohol ethoxylate or (ii) a capped alcohol ethoxylate; and a
detergent builder.
[0011] In this drilling fluid, it is believed that the non-ionic
surfactant acts to limit tar sand accretion to metal surfaces
perhaps by adsorbing onto surfaces or interfaces to change the
interfacial tensions and/or the electrical potentials. The
non-ionic surfactant may be effective in producing stearic barriers
for prevention of tar deposition. The adsorption of the surfactant
onto the bitumen will have the hydrophilic group oriented toward
the metal. Surfactant molecules adsorbed onto the bitumen particles
will have the hydrophilic group oriented toward the metal surfaces.
Since viscosifiers may be anionic, a non-ionic surfactant avoids a
reaction such as precipitation when operating with the
viscosifiers. It is desired that the non-ionic surfactants have a
water wetting, detergent characteristics, for example, that may
have a hydrophilic-lipophilic balance (HLB) number of 11 to 15.
Surfactants with an HLB over 15 may dissolve the bitumen and such
solubility is generally not desirable as this may lead to hole
instability, high washouts and waste volumes. The non-ionic
surfactant may also be low foaming. Modifying the structure of the
surfactant's molecule to keep the surface activity while producing
unstable foam can be realized by replacing the straight-chain
lipophilic group with a branched chain or by using two different
sized or shaped lipophilic groups. Changes may be made on the
hydrophilic part of the molecule by placing the second lipophobic
group into the molecule at some distance, for example a few carbon
atoms, or by putting two bulky lipophobic groups on the same carbon
atom. Some useful non-ionic surfactants include capped or branched
alcohol ethoxylate, such as for example ethoxylated alcohols,
ethoxylated propoxylated alcohols, etc. "Capped" implies that--OH
moieties are capped with a moiety such as a short alkyl group. Some
commercially available non-ionic surfactants that may be useful in
a drilling fluid may include one or more of: [0012] alkyl
polyethylene glycol ethers based on C10-guerbet alcohol and
ethylene oxide, for example, available as Lutensol XP 60.TM.,
Lutensol XP 69.TM., Lutensol XP 70.TM., Lutensol XP 79.TM.,
Lutensol XP 80.TM., Lutensol XP 89.TM., Lutensol XP 90.TM.,
Lutensol XP 99.TM. produced by BASF. The Lutensol(r) XP products
are manufactured by reacting the C10-alcohol with ethylene oxide in
stoichiometric proportions. The numeric portion of the product name
indicates the general degree of ethoxylation; [0013] chlorine
capped ethoxylated C10-14-ISO alcohols such as are available under
the trademark Antarox BL-330.TM. produced by Rhodia; [0014]
chlorine capped ethoxylated C9-11-ISO, C10 rich alcohols such as
are available under the trademark Antarox LF-330 produced by
Rhodia; [0015] end-capped guerbet alcohol ethoxylate for example,
available as Dehypon G 2084.TM. produced by Cognis; [0016] branched
secondary alcohol ethoxylates for example, available as Tergitol
TMN.TM. Series available from Dow.
[0017] The use of a non-ionic surfactant according to those
described gives a drilling fluid detergent characteristics.
[0018] A drilling fluid according to the present invention further
includes a detergent builder. As will be appreciated, a detergent
builder enhances the action of a detergent. Generally, it is
believed that builders operate as water wetting agents and remove
cations such as of calcium (Ca.sup.++) and magnesium (Mg.sup.++),
whose presence in the system may impair the detergent action. As
such, a builder may reduce the amount of surfactant to be used over
a system where no builder is used. This may offer numerous benefits
including reducing the amount of tar which is dissolved into the
drilling fluid, and thereby enhancing the reuse of the drilling
fluid.
[0019] Inorganic builders of interest include phosphates,
silicates, and oxygen releasing compounds such as perborates and
borates. Some builders that may be of interest include one or more
of: [0020] phosphates including trisodium phosphate (TSP) and
pyrophosphates, for example, tetra-potassium pyrophosphate (TKPP),
sodium acid pyrophosphate (STPP), etc. The phosphate type of
builders may also have beneficial dispersing properties,
considering that significant amounts of reactive clays may be
drilled and no additional dispersant may be required; [0021]
borates including for example sodium metaborate, sodium tetraborate
pentahydrate. While some builders may have some adverse
environmental effect, borates are believed to be environmentally
friendly and therefore may be environmentally of interest in a
drilling fluid formulation; [0022] zeolites including sodium
aluminum silicates readily replace their sodium ions with Ca2+ or
Mg2+ ions. Complex systems of zeolite/polyacrylate may also be
used; [0023] nitrilotriacetic acid (NTA); [0024]
ethylenediaminetetracetic acid (EDTA) and its salts; [0025]
citrates; or [0026] potassium or sodium silicates and
metasilicates. This type of builder may increase the friction
coefficient in the system.
[0027] The use of a builder in the drilling fluid enhances
performance of the surfactant such that generally less surfactant
needs to be used compared to a system without a builder and the
drilling fluid may be reused.
[0028] Where foam control is of interest, pyrophosphates have been
found to be particularly useful. If the drilling fluid exhibits
adverse foaming properties, pyrophosphate builder such as
tetra-potassium pyrophosphate (TKPP) or sodium acid pyrophosphate
(STPP) may be added. If drilling with pyrophosphate builder and
foaming begins to become an issue, the concentration of the
pyrophosphate may have to be topped up. This may occur, for
example, when drilling in clays, which tends to deplete
pyrophosphates.
[0029] In one embodiment, a water-based drilling fluid may be
prepared using 0.01-1.5% by weight of a non-ionic surfactant; and
0.01%-1.0% by weight of a detergent builder. In laboratory testing,
it was determined that a concentration of at least 0.5% by weight
of a non-ionic surfactant was necessary. However, in field tests it
was determined that useful activity could be achieved with
concentrations as low as 0.01% of the non-ionic surfactant up to
0.5% by weight as well as concentrations of 0.5%-1.5% by weight. As
well in laboratory testing, it was determined that a concentration
of at least 0.5% by weight of the detergent builder was necessary.
However, in field tests it was determined that useful activity
could be achieved with concentrations of builder as low as 0.01%
and through to but less than 0.5% by weight as well as
concentrations of 0.5%-1.0% by weight.
[0030] In one example embodiment, a water-based drilling fluid may
be prepared including: 0.01 to <0.5% by weight of an alkyl
polyethylene glycol ester and/or a chlorine capped ethoxylated
C9-11 (C10 rich) alcohol; and 0.01% to <0.5% by weight of a
phosphate-type builder, and/or a silicate-type builder.
[0031] A drilling fluid according to the present invention may also
include, if desired, a lubricant, also termed a secondary
surfactant. In field testing, it was determined that lubricant may
play a more significant role in anti-accretion and drill rate
performance than originally thought. In some drilling operations,
the anti-accreting results were observed without lubricant, but
often the addition of lubricant was found to improve the
anti-accretion results with the surfactant and builder. The
lubricant may act to soften the tar and provide a lubricating
action to assist drilling and running liners into long horizontal
sections of a wellbore. The lubricant may be non-ionic. High flash
point vegetable oils, such as those having a flash point greater
than 148.degree. C., may be of some use in the present drilling
fluids. Useful lubricants may include, for example, plant product
oils and derivatives thereof including fatty acid methyl esters for
example with an HLB of about 6, such as are commonly available as
vegetable oil or derivatives thereof, soybean oil or derivatives
such as soya methyl ester for example, commercially available as
SoyClear.TM. products by AG Environmental Products, LLC or canola
methyl ester for example, commercially available as Oleocal.TM.
canola methyl ester products by Lambent Technologies Corp., or
canola oil or its derivatives. Lubricants may be added to the
drilling fluid when the fluid is prepared, directly into the tanks
and may alternately or in addition by added by application first to
metal surfaces such as shale shakers, etc. at surface to thereby
enter the drilling fluid stream.
[0032] In one embodiment, a water-based drilling fluid may be
prepared using surfactant, builder and 0.01-1.5% by weight
secondary surfactant (also termed a lubricant) such as, for
example, a methyl ester of soybean oil. In laboratory testing, it
was determined that a concentration of at least 0.5% by weight of a
secondary surfactant was useful. However, in field tests it was
determined that useful activity could be achieved with
concentrations as low as 0.01% by weight of the secondary
surfactant through to the 0.5% by weight concentrations identified
in lab tests. As such, in the field the drilling fluid may be
useful with concentrations of 0.01 to <0.5% of a lubricant such
as a plant-based oil.
[0033] A drilling fluid according to the present invention may also
include, if desired, a viscosifier. A drilling fluid need not
include a viscosifier if there is sufficient hole cleaning. In
small diameter holes, for example, a viscosifier may not be needed.
However, viscosifiers provide carrying capacity to a drilling fluid
and, so, in some cases may be of interest. Viscosifiers, for
example, increase the viscosity of drilling fluid so that it can
carry cuttings along with the flow of drilling fluid. Viscosifiers
may also act to reduce fluid loss by inhibiting fluid infiltration
to the formation. Viscosifiers may prevent deposition or
re-deposition of the bitumen on metal surfaces by suspending the
tar and tar sand particles in the fluid. Some common viscosifiers
useful in embodiments of the present drilling fluid may include,
for example, any of: xanthan gum, wellan gum, schleroglucan and/or
guar gum.
[0034] In one embodiment, a water-based drilling fluid may be
prepared using surfactant, builder and 0.1-0.4% by weight
viscosifier. In laboratory testing, it was determined that a
concentration of at least 0.2% by weight of a viscosifier was
useful. However, in field tests it was determined that useful
activity could be achieved with concentrations as low as 0.1% by
weight of the viscosifier through to the 0.2% by weight
concentrations identified in lab tests.
[0035] Fluid loss reducers may also be used in a drilling fluid
according to the present invention if desired. Some common fluid
loss reducers include, for example, starches, PAC (polyanionic
cellulose) and/or CMC (carboxy methyl cellulose). Some of these
chemicals may also have a viscosifying function. The fluid loss
reducers may provide steric stabilization for the non-ionic
surfactants.
[0036] The drilling fluid may contain various defoamers such as
silicone defoamers, fatty alcohol ethoxylate defoamers, stearate
defoamers, etc., as desired, alone or in combination. In one
embodiment, silicone defoamer is used alone or with aluminum
stearate defoamer. In another embodiment, fatty alcohol ethoxylate
defoamer is used alone or with aluminum stearate defoamer in an
amount effect to control foaming.
[0037] Some components of the drilling fluid may operate best if pH
is controlled. For example, the fluid may be more basic with, for
example, the pH of the fluid maintained at 10 or more. In one
embodiment, the fluid is maintained at a pH of 10.5 or more.
Caustic or other basic additives may be employed for pH
control.
[0038] The drilling fluid is useful to inhibit tar accretion on
metal surfaces. However, it may also be used where torque and drag
issues are of concern, even apart from concerns regarding
accretion. In one aspect the drilling fluid can be used in a method
for drilling a wellbore into a heavy oil formation such as an oil
sand containing formation. In such a method, without the present
additive, tar and drill cuttings such as sand can adhere as
accretions to the metal surfaces of the drilling assembly, and
metal surfaces in the wellbore such as liners and casing. Thus, the
present method includes circulating the aqueous-based drilling
fluid, as described above, while operating a drilling assembly to
drill the wellbore.
[0039] In another aspect the drilling fluid may be used to remove
existing accretions on metal surfaces as by circulation through a
wellbore or washing of the wellbore surface systems.
[0040] The drilling fluid may be reused repeatedly by simply
removing the solids it contains.
[0041] It will be appreciated that a drilling assembly can include,
for example, a drill bit and possibly other cutting surfaces, a
drill string, and various control and monitoring subs.
[0042] It will also be appreciated, that it may not be necessary to
use the same drilling mud throughout an entire drilling operation.
For example, a drilling mud selected to control accretion may not
be required during drilling through the over burden. The method is
particularly useful during drilling wherein oil sand drill cuttings
are being produced and very useful where there is more frequent
contact between metal surfaces or metal surfaces and the wellbore
wall such as, for example, during drilling of the build section and
the horizontal section of a wellbore.
[0043] Where, during drilling using a drilling fluid according to
the present invention, accretions are being deposited to an
undesirable extent, the composition can be adjusted to, for
example, increase surfactant or secondary surfactant, to inhibit
further undesirable amounts of accretion and possibly to remove, at
least to some degree, those accretions already deposited.
Laboratory Examples
[0044] In the following laboratory examples, the test additives are
referenced by the product names set out in Table 1.
TABLE-US-00001 TABLE 1 % by Product Name Chemical Name weight
Product A Poly(oxy-1,2-ethanediyl), alpha 85
(phenylmethyl)-omega-(1,1,3,3- tetramethylbutyl) phenoxy- Glycols,
polyethylene, 15 mono[(1,1,3,3-tetramethylbutyl) phenyl] ether
Polyethylene glycol <3 Product B Oxirane, methyl-, polymer with
>99 oxyrane, mono(octylphenyl) ether, branched Polyethylene
glycol <1 Product C Modified polyethoxylated alcohol 100 Product
D C8-C10 ethoxylated propoxilated >98 Polyethylene glycol <2
Product E Butanedioic acid, octenyl- <63 Anionic surfactant
>35 Product F Ethoxylated 2,4,7,9-tetramethyl 5 100
decyn-4,7-diol Product G Poly(oxy-1,2-ethanediyl), alpha.(2- 100
propylheptyl)-omega-hydroxy- Product H Poly(oxy-1,2-ethanediyl),
alpha.(2- 100 propylheptyl)-omega-hydroxy- Product I
Poly(oxy-1,2-ethanediyl), 100 alpha-(2-propylheptyl)-omega-
hydroxy- Product J Poly(oxy-1,2-ethanediyl), 100
alpha-(2-propylheptyl)-omega- hydroxy- Product K Ethoxylated C9-10
alcohols >99.5 Product L Ethoxylated C8-10 alcohols >99.5
Product M Chlorine capped ethoxylated C10-14 >94 alcohols
Product N Chlorine capped ethoxylated C9-11 >94 alcohols, C10
rich Product O Triterpene, Sapogenin glycosides, 100 vegetal
steroid Product P Sodium tetraborate decahydrate 100 Product Q
Tetrapotassium pyrophosphate 100 Product R Sodium Metaborate 100
Product S Sodium silicate 82.5 Product T Zeolite 78-82 Product U
Pine oil 100 Product V Methyl ester of soybean oil 100 Product W
Turpentine oil 100 Product X Diethyl Phthalate 100 Product Y
Derived from canola oil 100 Product Z Sodium tetraborate
pentahydrate 100 Milligan MBTI Methyl ester of canola oil 100 P01D
Milligan MBTI Methyl ester of canola oil 100 P03D Milligan MBTI
Methyl ester of canola oil 100 P04D Milligan MBTI Methyl ester of
canola oil 100 P05D Milligan MBTI Methyl ester of canola oil 100
P06D
[0045] Tables 2 to 14 includes results from various tests
conducted, wherein the samples are prepared by adding 200 mL of
water in a mixing cup followed by the test additives and 40 g of
tar sand core material. Each sample is then mixed 15 to 20 seconds
on a multimixer prior to placement in 260 mL rolling cell with a
corresponding pre-weighed metal bar. The samples are rolled for 30
min. Then the tar accretion is measured by weight gain of the bars
and by observation. The tests are run at room temperature.
TABLE-US-00002 TABLE 2 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Blank 1.3 100%
100% 2 Product A 5 ** 3.0 50% 5% 3 Product B 5 ** 2.0 40% 60% 4
Product C 5 **** 3.4 90% 95% Milky in water Thin 5 Product D 5 *
1.9 90% 100% 6 Product E 5 * 3.5 95% 100% Milky in water Thick
TABLE-US-00003 TABLE 3 Tar on bar Conc. Weight Sample Number
Product L/m3 Foaming (g) Tar on Cell Tar on Lid Notes 1 Blank 2.6
100% 80% 2 Product B 10 ** 3.1 trace Trace 3 Product B 5 ** 1.6 50%
35% Product Y 10 4 Product B 10 **** 3.8 10% 30% Product Y 10 5
Product B 5 *** 2.8 80% 30% Product Y 20 6 Product Y 10 1.8 100%
100% Oil and tar separates from water
TABLE-US-00004 TABLE 4 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Product A 10 **
4.5 60% 2% 2 Product A 20 **** 5.6 1% 0% The tar is sticking to the
bar 3 Product A 5 ** 0.6 90% 100% Product V 10 4 Product A 5 * 1.4
90% 10% Product V 20 5 Product A 10 ** 2.0 95% 5% Product V 20 6
Product V 30 0.3 Oil with Oil with dissolved tar dissolved tar
TABLE-US-00005 TABLE 5 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Product A 5 **
1.5 95% 3% Product W 10 2 Product A 10 *** 1.1 20% 25% Product W 10
3 Product A 10 *** 0.5 20% 100% Limonene 20 4 Product A 5 ** 1.1
20% 40% Limonene 10 5 Product A 10 *** 2.7 20% 25% Limonene 10 6
Product A 10 *** 2.6 15% 100% Limonene 20
TABLE-US-00006 TABLE 6 Tar on bar Sample Conc. Weight Tar Number
Product L/m3 Foaming (g) Tar on Cell on Lid Notes 1 Product F 5 *
2.8 90% 40% 2 Product G 5 ** 1.9 90% 5% 3 Product H 5 **** 1.1 90%
95% Bottom of cell clean 4 Product I 5 **** 1.8 100% 60% 5 Product
J 30 ***** 2.5 80% 40% 6 Limonene 30 0.2 0% 5% Film
TABLE-US-00007 TABLE 7 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Product A 10 --
0.1 No No Some Limonene 20 oily Product Q 5 film 2 Product B 10 ***
0.1 No No Some Limonene 20 oily Product Q 5 film 3 Product D 10 **
0.1 No No Some Limonene 20 oily Product Q 5 film 4 Product E 10 **
0.1 No No Some Limonene 20 oily Product Q 5 film 5 Product G 10
**** 0.1 No No Totally Limonene 20 clean Product Q 5 6 Product H 10
**** 0.1 No No Totally Limonene 20 clean Product Q 5
TABLE-US-00008 TABLE 8 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Product G 10 *
-- -- -- Limonene 15 Product Q 5 Defoamer 5 Silicone 2 Product H 10
* -- -- -- Limonene 15 Product Q 5 Defoamer 5 Silicone 3 Product G
10 * -- -- -- Product X 15 Product Q 5 Defoamer 5 Silicone 4
Product H 10 * -- -- -- Product X 15 Product Q 5 Defoamer 5
Silicone 5 Product G 10 * -- -- -- Clean- Product V 15 est Product
Q 5 Defoamer 5 Silicone 6
TABLE-US-00009 TABLE 9 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Xanthan 5 * --
-- -- Gum Product H 5 Product V 10 Product Q 5 Defoamer 10 Silicone
2 Xanthan 5 * -- -- -- Gum Product K 5 Product V 10 Product Q 5
Defoamer 5 Silicone 3 Xanthan 5 * -- -- -- Gum Product L 10 Product
V 5 Product Q 5 Defoamer 5 Silicone 4 Xanthan 5 * -- 5% -- Gum 5
Product M 10 Product V 5 Product Q -- Defoamer Silicone 5 Xanthan 5
* -- -- -- Gum 5 Product N 10 Product V 5 Product Q -- Defoamer
Silicone 6 Xanthan 5 * 1.4 trace -- Has an Gum oily Product O 5
film Product V 10 Product Q 5 Defoamer -- Silicone
TABLE-US-00010 TABLE 10 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Blank 12.8 30%
90% 2 Product N 10 ** -- -- -- Product V 10 Product Q 5 Defoamer --
Silicone 3 Product N 10 ** 0.7 -- -- Product V 10 Product P 5
Defoamer -- Silicone 4 Product N 10 ** 0.5 5% -- Product V 10
Product X 10 Product P 5 Defoamer -- Silicone 5 Product P 5 7.4 50%
100% 6 Product Q 5 3.2 15% 80%
TABLE-US-00011 TABLE 11 Tar on Sample Conc. bar Weight Number
Product L/m3 Foaming (g) Tar on Cell Tar on Lid Notes 1 Xanthan 4
-- -- -- -- Gum Product H 5 Product V 10 Product Q 5 2 Xanthan 4 --
-- trace -- Easy to Gum clean with water Product H 5 Product V 10
Product S 5 3 Xanthan 4 -- -- 5% -- Easy to Gum clean with water
Product H 5 Product V 10 Product T 5 100 4 Xanthan 4 -- -- -- --
Gum Product N 5 Product V 10 Product Q 5 5 Xanthan 4 -- -- trace --
Easy to Gum clean with water Product N 5 Product V 10 Product S 5 6
Xanthan 4 -- -- 5% -- Easy to Gum clean with water Product N 5
Product V 10 Product T 5 100
TABLE-US-00012 TABLE 12 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Xanthan 4.2 --
-- -- -- -- Gum Product H 5 Milligan 10 MBTI 5 P01D Product Q 2
Xanthan 4.2 -- -- -- -- -- Gum Product H 5 Milligan 10 MBTI 5 P03D
Product Q 3 Xanthan 4.2 -- -- -- -- -- Gum Product H 5 Milligan 10
MBTI 5 P04D Product Q 4 Xanthan 4.2 -- -- -- -- -- Gum Product H 5
Milligan 10 MBTI 5 P05D Product Q 5 Xanthan 4.2 -- -- -- -- -- Gum
Product H 5 Milligan 10 MBTI 5 P06D Product Q 6 Xanthan 4.2 -- --
-- -- -- Gum Product H 5 Product U 10 Product Q 5
TABLE-US-00013 TABLE 13 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Blank -- 11.4
30% -- -- 2 Xanthan 4.0 -- -- -- -- -- Gum Product H 5 Product V 10
Product Q 5 Defoamer 2 Silicone 3 Xanthan 4.0 -- -- -- -- -- Gum 5
Product H 10 Product V 5 Product R 2 Defoamer Silicone 4 Xanthan
4.0 -- -- -- -- -- Gum Product H 5 Product V 10 Product Z 5
Defoamer 2 Silicone 5 Xanthan 4.0 -- -- -- -- -- Gum Product H 5
Milligan 10 MBTI 5 P06D 2 Product Q Defoamer Silicone 6 Xanthan 4.0
-- -- -- -- -- Gum Product H 5 Product U 10 Product Q 5 Defoamer 2
Silicone
TABLE-US-00014 TABLE 14 Tar on bar Sample Conc. Weight Tar on Tar
Number Product L/m3 Foaming (g) Cell on Lid Notes 1 Blank -- 7.6
100% Trace 2 Xanthan 4.0 -- 2.1 Trace Trace Gum Product V 10 3
Xanthan 4.0 -- 1.6 Trace Trace Gum Product V 10 Product H 5 4
Xanthan 4.0 -- 1.8 Trace Trace Gum Product V 30 5 Xanthan 4.0 --
0.5 Trace Clean Gum Product H 10 Product Q 5 6 Xanthan 4.0 -- 2.4
Trace Clean Gum Product H 10 Product V 10
[0046] Example 15. Lubricity tests were conducted using a baroid
lubricity meter, which provides a reading of the friction
co-efficient (CoF). A solution of xanthan gun (4 kg/m3) in water
was tested and generated a CoF reading of 0.30. Another aqueous
solution was prepared including xanthan gun (4 kg/m3), alkyl
polyethylene glycol ether (Lutensol XP 79) (10 L/m3), and soya
methyl ester (50 L/m3) and this generated a CoF reading of 0.20.
The CoF was reduced from 0.3 to 0.2 with the addition of the two
products.
Field Tests
Example A
[0047] Background: In Alberta, Canada; Drilled 156 mm hole into the
Ft. McMurray formation. The Ft. McMurray formation is an
unconsolidated sandstone containing 30% v/v bitumen. Drilling rate
was approximately 200 m/hr.
[0048] Drilling Fluid: A fresh water based drilling fluid
including: xanthan gum for viscosity, a polyanionic cellulose
polymer (Drispac Regular) for fluid loss control, a silicone based
defoamer, caustic to control the pH at 10.5, a deflocculant
additive (Desco CF), an amine based shale inhibitor and a builder
(625 kg of TKPP) was used to drill into the Ft. McMurray formation.
The shaker screens were monitored for accretion. When sand started
to stick to the shakers, one pail (20 L) of surfactant (Lutensol XP
79) and one pail (20 L) of a soya bean-based lubricant were added
to the drilling fluid, equating to concentrations of approximately
0.04% of each of the surfactant and the lubricant in the drilling
fluid. After addition of the surfactant and lubricant, accretion no
longer occurred on the shaker screens.
[0049] As drilling proceeded into a lateral, horizontal section in
the formation, concentrations of 1 to 3 L/m3 of the surfactant were
required to continue to prevent accretion.
Example B
[0050] Background: In Alberta, Canada; Drilled 311 mm hole to
Intermediate Casing Depth of 665 mMD and casing set at .about.90
degrees inclination in the Ft. McMurray formation. Set and cement
244.5 mm casing.
[0051] Drilling Fluid: A fresh water based drilling fluid
including: xanthan gum for viscosity, a polyanionic cellulose
polymer (Drispac Regular) for fluid loss control, a silicone based
defoamer, caustic to control the pH at 10.5, a deflocculant
additive (Desco CF), an amine based shale inhibitor and a builder
(625 kg of TKPP) was used to drill into the Ft. McMurray formation.
Just above the Ft. McMurray bitumen 100 L of anti-accretion
surfactant (Lutensol XP 79) and 100 L of soya bean/canola oil-based
lubricant were added to approximately 58.4 m3 of circulating volume
of drilling fluid. This equates to concentrations of approximately
1.7 L/m3 of both the surfactant and the lubricant in the drilling
fluid. This section was successfully drilled, cased and cemented
terminating in the Ft. McMurray formation.
Example C
[0052] Background: In Alberta, Canada; Drilled 311 mm hole to
Intermediate Casing Depth of 682 mMD and casing set at .about.90
degrees inclination in the Ft. McMurray formation. Set and cement
244.5 mm casing.
[0053] Drilling Fluid: A fresh water based drilling fluid including
xanthan gum for viscosity, a polyanionic cellulose polymer (Drispac
Regular) for fluid loss control, a silicone based defoamer, caustic
to control the pH at 10.5, an amine based shale inhibitor and a
builder (675 kg of TKPP) was used to drill into the Ft. McMurray
formation. Just above the Ft. McMurray bitumen 20 L of
anti-accretion surfactant (Lutensol XP 79) and 20 L of plant
oil-based lubricant (vegetable oil) were added to approximately
92.9 m3 of circulating volume of drilling fluid. This equates to
concentrations of approximately 0.22 L/m3 of both the surfactant
and the lubricant in the drilling fluid. This section was
successfully drilled, cased and cemented terminating in the Ft.
McMurray formation.
[0054] The previous description of the disclosed embodiments is
provided to enable any person skilled in the art to make or use the
present invention. Various modifications to those embodiments will
be readily apparent to those skilled in the art, and the generic
principles defined herein may be applied to other embodiments
without departing from the spirit or scope of the invention. Thus,
the present invention is not intended to be limited to the
embodiments shown herein, but is to be accorded the full scope as
defined in the claims, wherein reference to an element in the
singular, such as by use of the article "a" or "an" is not intended
to mean "one and only one" unless specifically so stated, but
rather "one or more". All structural and functional equivalents to
the elements of the various embodiments described throughout the
disclosure that are known or later come to be known to those of
ordinary skill in the art are intended to be encompassed by the
elements of the claims. Moreover, nothing disclosed herein is
intended to be dedicated to the public regardless of whether such
disclosure is explicitly recited in the claims. No claim element is
to be construed under the provisions of 35 USC 112, sixth
paragraph, unless the element is expressly recited using the phrase
"means for" or "step for".
* * * * *