CA2506117A1 - Water based drilling fluid for shallow wells - Google Patents
Water based drilling fluid for shallow wells Download PDFInfo
- Publication number
- CA2506117A1 CA2506117A1 CA 2506117 CA2506117A CA2506117A1 CA 2506117 A1 CA2506117 A1 CA 2506117A1 CA 2506117 CA2506117 CA 2506117 CA 2506117 A CA2506117 A CA 2506117A CA 2506117 A1 CA2506117 A1 CA 2506117A1
- Authority
- CA
- Canada
- Prior art keywords
- fluid
- weight
- blended
- amount
- oil
- 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.)
- Abandoned
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
-
- 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
- C09K8/32—Non-aqueous well-drilling compositions, e.g. oil-based
- C09K8/36—Water-in-oil emulsions
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Earth Drilling (AREA)
- Lubricants (AREA)
Abstract
A blend of viscosifiers, fluid loss reducers, clay swelling inhibitors and "mud-ring" agents.
This blend is in liquid form and is added to water to make drilling fluid for shallow well applications.
This blend is in liquid form and is added to water to make drilling fluid for shallow well applications.
Description
WATER BASED DRILLING FLUID FOR SHALLOW WELLS
BACKGROUND OF THE INVENTION
01 Conventional shallow wells are drilled with water under the surface shoe.
The drilling mud is made thicker at a point known as the mud-up to protect the production zone and facilitate running electric logs and running casing. Usually this point occurs at a few hundred meters before the total depth of the well is reached. A typical shallow well is drilled within 48 hrs. Inefficient mixing and time do not permit attaining an efficient mix or the cost-effective optimization of properties.
02 To make the mud thicker a bentonite product such as Wyoming Bentonite, is added to the water. Other chemicals added may include a fluid loss reducer such as a starch or polyanionic cellulose such as Drispac, pH control such as caustic or citric acid and mud ring control such as sodium pyrophosphate. Due to time constraints in drilling the well and inefficient mixing, the chemicals added rarely have enough time to properly yield. This means that to obtain the desired properties of the mud system, over treatment of the chemicals into the drilling fluid system is often the norm.
SUMMARY OF THE INVENTION
03 This invention combines a number of chemical products into one package and allows for rapid delivery of the chemicals to the drilling system, improving chemical performance and reducing waste.
04 A blend of solids and liquids are suspended in oil, which may be any type of environmentally friendly mineral oil, for rapid dispersion when added to water. This blend includes viscosifiers, a fluid loss reducer, surfactants to remove the oil from the solid particles, clay, pH control and "mud-ring" additives. The blended fluid of solids and liquids is mixed together to form a suspension of solids in oil before addition to a water tank. The blended suspension of solids in oil is mixed in a mixing plant and stored in pails. It is then transported to the well site where it is added to the water in the tank at the drilling rig to make "drilling mud". Simple agitation in the water tank produces a drilling fluid.
05 Further summary of the invention is found in the claims, particularly referring to specific ranges of components of the blended fluid.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
06 In this patent document, the word comprising is used in its inclusive sense, and does not exclude other steps or product components being present. The indefinite article before a product component, eg viscosifier, does not exclude more than one type of that product component being present. In this patent document, a shallow well is a well drilled to a depth of less than 1500 meters. A blend or blended fluid in this patent document is a suspension of solids in oil, and may include a fraction of other liquid.
07 A blend of solids and liquids are suspended in oil for rapid dispersion when added to water. This blend includes viscosfiers, a fluid loss reducer, surfactants to remove the oil from the solid particles, clay, pH control and a "mud-ring" additive. The blended fluid of solids and liquids is mixed together to form a suspension of solids in oil before addition to a water tank (suction tank) at a well site. The fluid may be blended and stored in a pail before adding to the suction tank to produce a drilling fluid. Agitation of the fluid in the tank causes rapid dispersion of the solid component in the water. The components added to the blend at a well site may be selected to match the requirements of the well. The system may be hauled to the next drilling location and used to drill surtace hole. In this case, the alkalinity may be adjusted to make the system thick again, or otherwise adjusted as required.
08 The blend of solids and liquids are suspended in a mineral oil or any environmentally friendly oil such as HT40NTM or HT30NT""from Petro-Canada of Calgary, Alberta, Canada, AmodrilT"" (from Amoco), EnvirodrilTM (from Shell), DriIIsoIT"" (from Enerchem), SyndrilT""
(from SynOil Fluids), BiodieselT"" (from Bio-diesel Canada), Methyl canolate, BayoIT"", ExxsoIT"" (from Exxson), SheIIsoITM (from Shell), glycols, or vegetable oils such as canola oil or soya oil. The oil may be present in the range of 35% to 50% by weight of the total blended fluid, for example 37% by weight. All weight percents are expressed as percentage of the total blended fluid. An environmentally friendly oil is an oil with a high flash point, readily biodegradable in the environment and safe to use from a human hygiene perspective (i.e. reduced amounts or contains zero concentrations of aromatic chemical components).
BACKGROUND OF THE INVENTION
01 Conventional shallow wells are drilled with water under the surface shoe.
The drilling mud is made thicker at a point known as the mud-up to protect the production zone and facilitate running electric logs and running casing. Usually this point occurs at a few hundred meters before the total depth of the well is reached. A typical shallow well is drilled within 48 hrs. Inefficient mixing and time do not permit attaining an efficient mix or the cost-effective optimization of properties.
02 To make the mud thicker a bentonite product such as Wyoming Bentonite, is added to the water. Other chemicals added may include a fluid loss reducer such as a starch or polyanionic cellulose such as Drispac, pH control such as caustic or citric acid and mud ring control such as sodium pyrophosphate. Due to time constraints in drilling the well and inefficient mixing, the chemicals added rarely have enough time to properly yield. This means that to obtain the desired properties of the mud system, over treatment of the chemicals into the drilling fluid system is often the norm.
SUMMARY OF THE INVENTION
03 This invention combines a number of chemical products into one package and allows for rapid delivery of the chemicals to the drilling system, improving chemical performance and reducing waste.
04 A blend of solids and liquids are suspended in oil, which may be any type of environmentally friendly mineral oil, for rapid dispersion when added to water. This blend includes viscosifiers, a fluid loss reducer, surfactants to remove the oil from the solid particles, clay, pH control and "mud-ring" additives. The blended fluid of solids and liquids is mixed together to form a suspension of solids in oil before addition to a water tank. The blended suspension of solids in oil is mixed in a mixing plant and stored in pails. It is then transported to the well site where it is added to the water in the tank at the drilling rig to make "drilling mud". Simple agitation in the water tank produces a drilling fluid.
05 Further summary of the invention is found in the claims, particularly referring to specific ranges of components of the blended fluid.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
06 In this patent document, the word comprising is used in its inclusive sense, and does not exclude other steps or product components being present. The indefinite article before a product component, eg viscosifier, does not exclude more than one type of that product component being present. In this patent document, a shallow well is a well drilled to a depth of less than 1500 meters. A blend or blended fluid in this patent document is a suspension of solids in oil, and may include a fraction of other liquid.
07 A blend of solids and liquids are suspended in oil for rapid dispersion when added to water. This blend includes viscosfiers, a fluid loss reducer, surfactants to remove the oil from the solid particles, clay, pH control and a "mud-ring" additive. The blended fluid of solids and liquids is mixed together to form a suspension of solids in oil before addition to a water tank (suction tank) at a well site. The fluid may be blended and stored in a pail before adding to the suction tank to produce a drilling fluid. Agitation of the fluid in the tank causes rapid dispersion of the solid component in the water. The components added to the blend at a well site may be selected to match the requirements of the well. The system may be hauled to the next drilling location and used to drill surtace hole. In this case, the alkalinity may be adjusted to make the system thick again, or otherwise adjusted as required.
08 The blend of solids and liquids are suspended in a mineral oil or any environmentally friendly oil such as HT40NTM or HT30NT""from Petro-Canada of Calgary, Alberta, Canada, AmodrilT"" (from Amoco), EnvirodrilTM (from Shell), DriIIsoIT"" (from Enerchem), SyndrilT""
(from SynOil Fluids), BiodieselT"" (from Bio-diesel Canada), Methyl canolate, BayoIT"", ExxsoIT"" (from Exxson), SheIIsoITM (from Shell), glycols, or vegetable oils such as canola oil or soya oil. The oil may be present in the range of 35% to 50% by weight of the total blended fluid, for example 37% by weight. All weight percents are expressed as percentage of the total blended fluid. An environmentally friendly oil is an oil with a high flash point, readily biodegradable in the environment and safe to use from a human hygiene perspective (i.e. reduced amounts or contains zero concentrations of aromatic chemical components).
2 09 The blended suspension includes viscosifiers. The viscosifier is present in the range of 20% to 50% by weight, as for example 35% guar by weight. If Xanthan is used, the xanthan may be present in the amount of 1 % to 10% by weight, for example 2%
by weight, in addition to one or more other viscosifiers, such as guar. The guar may be unmodified or modified guar and the xanthan may be Xanvis'n" both available from numerous suppliers.
Oil suspended guar systems in themselves are well known in the art, such as in US patent #
5969012. The viscosifier may be a water dispersible or soluble hydrophilic polysaccharide such as xanthan or guar gum previously mentioned or gellan gum, algin, locust bean gum, derivatized locust bean gum, carrageenan, derivatized guar gum, cellulosics such as carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose and polyanionic cellulose, succinoglucans, polyacrylamides, starch and starch derivatives or mixtures of any of these components.
A fluid loss reducer such as DrispacT"" available from chemical suppliers such as Canamara United in Calgary, Alberta, Canada is added to the blended fluid in an amount ranging from about 5 to 15% by weight, for example 11 % by weight. Surfactants such as nonylethoxy phenol (for example, NEP-9T"') available from Canadian Colors of Edmonton, Alberta, Canada to remove the oil from the solid particles, are added to the blended fluid in the amount of 2% to 5% by weight. The surfactants that work well in this application are specifically surfactants that emulsify oil in water; they are used to take the oil off the solids present in the mixture when the total mixture is added to water. Soda ash, which is commonly available, may be added to improve the hydratability of the guar by controlling the pH of the blend. pH controllers are primarily added to help the biopolymers viscosify faster in water. pH control of drilling fluid is well known in the art and need not be further described here.
11 A mud-ring agent such as Dril Kan MRPTM available from Millennium Technologies should be added to the blended fluid in the amount of 1 to 15% by weight, for example, 8%
by weight, to inhibit the formation of mud deposits on the drill pipe. Various mud ring agents may be used that are effective in dispersing or inhibiting a mud ring. Typical mud-ring agents are surfactant based molecules and can be classified as soaps. They disperse or inhibit a mud ring by coating the individual clay particles, which stops them from joining
by weight, in addition to one or more other viscosifiers, such as guar. The guar may be unmodified or modified guar and the xanthan may be Xanvis'n" both available from numerous suppliers.
Oil suspended guar systems in themselves are well known in the art, such as in US patent #
5969012. The viscosifier may be a water dispersible or soluble hydrophilic polysaccharide such as xanthan or guar gum previously mentioned or gellan gum, algin, locust bean gum, derivatized locust bean gum, carrageenan, derivatized guar gum, cellulosics such as carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose and polyanionic cellulose, succinoglucans, polyacrylamides, starch and starch derivatives or mixtures of any of these components.
A fluid loss reducer such as DrispacT"" available from chemical suppliers such as Canamara United in Calgary, Alberta, Canada is added to the blended fluid in an amount ranging from about 5 to 15% by weight, for example 11 % by weight. Surfactants such as nonylethoxy phenol (for example, NEP-9T"') available from Canadian Colors of Edmonton, Alberta, Canada to remove the oil from the solid particles, are added to the blended fluid in the amount of 2% to 5% by weight. The surfactants that work well in this application are specifically surfactants that emulsify oil in water; they are used to take the oil off the solids present in the mixture when the total mixture is added to water. Soda ash, which is commonly available, may be added to improve the hydratability of the guar by controlling the pH of the blend. pH controllers are primarily added to help the biopolymers viscosify faster in water. pH control of drilling fluid is well known in the art and need not be further described here.
11 A mud-ring agent such as Dril Kan MRPTM available from Millennium Technologies should be added to the blended fluid in the amount of 1 to 15% by weight, for example, 8%
by weight, to inhibit the formation of mud deposits on the drill pipe. Various mud ring agents may be used that are effective in dispersing or inhibiting a mud ring. Typical mud-ring agents are surfactant based molecules and can be classified as soaps. They disperse or inhibit a mud ring by coating the individual clay particles, which stops them from joining
3 together. Mud ring agents also include drilling detergent, LIQUISPERSET"', DriIconT"" from suppliers such as Millenium and Canamara.
12 Clay may be added as required, such as a bentonite, as for example SD-1 T""
available from Elementis, for example in the amount of between 1 and 4% of the total weight of the blended fluid, for example 2% by weight. The organophilic clay is used to suspend solids in oil based products, that is to stop settling of the solids when sitting in a packaged form. Another supplier is Southern Clay. The order in which the solids are added to the oil is preferably first the clay, then all the rest of the solids and liquids.
13 Additional viscosity can be achieved by using viscosifiers that can be crosslinked.
Crosslinked bio-polymers can impart very high viscosities in short time periods. Suitable cross-linked bio-polymers are found in US patent # 6642185, 6177385, 4579942.
14 Benefits to the liquid suspension include reduced mixing times. The system requires no mixing equipment (pumps and hoppers). The product is added directly to the suction tank, above the agitator. Thus less equipment is required to mix products.
Components disperse efficiently eliminating the "fish eye" and "clay ball" problem associated with conventional systems. Conventional clay based systems do not have time to hydrate and yield efficiently when drilling shallow wells, whereas in the present invention, components yield efficiently. All components are in one package, as for example a pail.
For systems formulated with the product, it is possible to adjust properties for logging or circulating casing much more readily than with conventional systems. It also reduces the number of products to be managed (inventory and mixing) on the drilling location. Damage to inventory and inventory shrinkage of products will not occur to products in pails.
15 The system costs as much as a conventional gel / chem system. The savings are be realized in trucking and logistics. Enough product will fit in a van to drill 8 - 10 wells compared to 2 - 3 with conventional drilling fluid products. Immaterial modifications may be made to the composition and method disclosed here without departing from the invention.
12 Clay may be added as required, such as a bentonite, as for example SD-1 T""
available from Elementis, for example in the amount of between 1 and 4% of the total weight of the blended fluid, for example 2% by weight. The organophilic clay is used to suspend solids in oil based products, that is to stop settling of the solids when sitting in a packaged form. Another supplier is Southern Clay. The order in which the solids are added to the oil is preferably first the clay, then all the rest of the solids and liquids.
13 Additional viscosity can be achieved by using viscosifiers that can be crosslinked.
Crosslinked bio-polymers can impart very high viscosities in short time periods. Suitable cross-linked bio-polymers are found in US patent # 6642185, 6177385, 4579942.
14 Benefits to the liquid suspension include reduced mixing times. The system requires no mixing equipment (pumps and hoppers). The product is added directly to the suction tank, above the agitator. Thus less equipment is required to mix products.
Components disperse efficiently eliminating the "fish eye" and "clay ball" problem associated with conventional systems. Conventional clay based systems do not have time to hydrate and yield efficiently when drilling shallow wells, whereas in the present invention, components yield efficiently. All components are in one package, as for example a pail.
For systems formulated with the product, it is possible to adjust properties for logging or circulating casing much more readily than with conventional systems. It also reduces the number of products to be managed (inventory and mixing) on the drilling location. Damage to inventory and inventory shrinkage of products will not occur to products in pails.
15 The system costs as much as a conventional gel / chem system. The savings are be realized in trucking and logistics. Enough product will fit in a van to drill 8 - 10 wells compared to 2 - 3 with conventional drilling fluid products. Immaterial modifications may be made to the composition and method disclosed here without departing from the invention.
4
Claims (13)
1. A method of producing a drilling fluid at a well site, the method comprising the steps of:
blending an environmentally friendly oil with a viscosifier, fluid loss reducer, surfactant, clay, mud-ring agent and pH controller to form a blended fluid comprising a suspension of solids and liquids in oil; and after blending, adding the blended fluid to water in a water tank at a well site to produce a drilling fluid.
blending an environmentally friendly oil with a viscosifier, fluid loss reducer, surfactant, clay, mud-ring agent and pH controller to form a blended fluid comprising a suspension of solids and liquids in oil; and after blending, adding the blended fluid to water in a water tank at a well site to produce a drilling fluid.
2. The method of claim 1 in which the blending takes place above ground at the well.
3. The method of claim 1 or 2 in which the environmentally friendly oil is present in the amount of between 35% and 50% by weight of the blended fluid.
4. The method of claim 1, 2 or 3 in which the viscosifier is present in the amount of between 20% and 50% by weight of the blended fluid.
5. The method of any one of claims 1-4 in which the fluid loss reducer is present in the amount of between 5% and 15% of the weight of the blended fluid.
6. The method of any one of claims 1-5 in which the surfactant is present in the amount of between 2% and 5% of the weight of the blended fluid.
7. The method of any one of claims 1-6 in which clay is present in the amount of between 1% and 4% of the weight of the blended fluid.
8. The method of any one of claims 1-7 in which the environmentally friendly oil further comprises xanthan in the amount of between 1% and 10% by weight of the blended fluid.
9. The method of any one of claims 1-8 in which the mud-ring agent is present in the amount of between 1% and 15% by weight of the blended fluid.
10. The method of any one of claims 1-9 further comprising the step of injecting the drilling fluid into a well.
11. The method of any one of claims 1-10 in which the well site is for a shallow well.
12. The method of any one of claims 1-11 in which blending occurs at the well site.
13. The method of any one of claims 1-11 in which blending occurs away from the well site, and the blended fluid is transported to the well site in pails.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2506117 CA2506117A1 (en) | 2005-04-28 | 2005-04-28 | Water based drilling fluid for shallow wells |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2506117 CA2506117A1 (en) | 2005-04-28 | 2005-04-28 | Water based drilling fluid for shallow wells |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2506117A1 true CA2506117A1 (en) | 2006-10-28 |
Family
ID=37193915
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2506117 Abandoned CA2506117A1 (en) | 2005-04-28 | 2005-04-28 | Water based drilling fluid for shallow wells |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2506117A1 (en) |
-
2005
- 2005-04-28 CA CA 2506117 patent/CA2506117A1/en not_active Abandoned
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1339811B1 (en) | Environmentally acceptable fluid polymer suspension for oil field services | |
| Fink | Oil field chemicals | |
| US4863980A (en) | Organophilic modified polymers | |
| US20150072901A1 (en) | Lost circulation and fluid loss materials containing guar chaff and methods for making and using same | |
| US5801127A (en) | Olive pulp additive in drilling operations | |
| US11149519B2 (en) | Smart filtrate for strengthening formations | |
| US20170190956A1 (en) | Aqueous emulsions for crosslinking | |
| US20040211563A1 (en) | Compositions and methods for sealing formations | |
| WO2012087388A1 (en) | Hydraulic fracturing with slick water from dry blends | |
| CN101910355A (en) | Viscoelastic surfactant based wellbore fluids and methods of use | |
| CN102197107A (en) | High performance water based fluids | |
| CN106661929B (en) | Water-based wellbore servicing fluid containing high temperature fluid loss control additives | |
| US10787598B2 (en) | Shale inhibitors based on cationic tamarind gum, and drilling fluid comprising the shale inhibitor | |
| US20040063588A1 (en) | Delivery system for drilling fluid dispersible additive tablet and associated methods | |
| Mahto | Effect of activated charcoal on the rheological and filtration properties of water based drilling fluids | |
| US20180305600A1 (en) | Exothermic reactants for use in subterranean formation treatment fluids | |
| RU2664987C2 (en) | Utilization of boron as crosslinking agent in emulsion system | |
| US20120028853A1 (en) | Drilling fluid, drilling fluid additive, methods of making and using, such fluid and additive, methods of operating a well | |
| RU2230092C2 (en) | Drilling muds | |
| US20230203361A1 (en) | Wellbore stability compositions comprising nanoparticles | |
| CA2506117A1 (en) | Water based drilling fluid for shallow wells | |
| US2782163A (en) | Emulsion drilling fluid composition and method | |
| US10787605B2 (en) | Methods and thermally stable aqueous borate-based cross-linking suspensions for treatment of subterranean formations | |
| WO2011011878A1 (en) | Drilling fluid additive comprising an oil and multiple guar compounds | |
| Abhulimen et al. | Modelling the effectiveness of environmental friendly bioenhancers additives in novel drilling fluid systems |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |