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
  • C09K8/32—Non-aqueous well-drilling compositions, e.g. oil-based
  • C09K8/36—Water-in-oil emulsions
• • 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
  • C09K8/34—Organic liquids

Definitions

• the invention describes new drilling fluids and invert drilling muds based thereon, which are characterized by high ecological compatibility and, at the same time, good standing and usage properties.
• An important area of application for the new drilling mud systems is offshore drilling for the development of oil and / or natural gas deposits, whereby the invention is particularly concerned with providing technically usable drilling muds with high ecological compatibility.
• the use of the new drilling fluid systems is particularly important in the marine area, but is not limited to this.
• the new flushing systems can also be used in general for land-based drilling, for example for geothermal drilling, for water drilling, for performing geoscientific drilling and for drilling in the mining sector. In principle, it also applies here that the ecotoxic problem area is substantially simplified by the drilling oil liquids selected according to the invention.
• Oil-based drilling fluids are generally used as so-called invert emulsion muds, which consist of a three-phase system: oil, water and finely divided solids. These are preparations of the type of W / O emulsions, i.e. H. the aqueous phase is heterogeneously finely dispersed in the closed oil phase.
• a plurality of additives, in particular emulsifiers, are provided to stabilize the overall system and to set the desired performance properties or emulsifier systems, weighting agents, fluid loss additives, alkali reserves, viscosity regulators and the like.
• emulsifiers are provided to stabilize the overall system and to set the desired performance properties or emulsifier systems, weighting agents, fluid loss additives, alkali reserves, viscosity regulators and the like.
• ester oils of the type concerned do not behave in the same way as the mineral oil fractions based on pure hydrocarbons used to date.
• ester oils are also subject to partial hydrolysis, particularly in W / O invert drilling fluid. In this way free carboxylic acids are formed.
• the older applications P 38 42 659.5 and P 38 42 703.6 (D 8523 and D 8524) describe the problems that are triggered by this and give suggestions for their solution. Further modifications of usable ester oils are described in the earlier patent applications P 39 07 391 .2 and P 39 07 392.0 (D 8606 and D 8607).
• the subject of these earlier applications is the use of ester oils based on selected monocarboxylic acids or monocarboxylic acid mixtures and monofunctional and optionally multifunctional alcohols.
• the older applications describe that the esters or ester mixtures disclosed therein not only enable satisfactory rheological properties to be set in the fresh drilling fluid, but that it is also possible to work in the drilling fluid with the use of selected known alkali reserves and in this way to avoid undesired Retain corrosion.
• the alkali reserve - especially when using ester oils based on carboxylic acids with at least 6 carbon atoms - is the addition of lime (calcium hydroxide or lime) and / or the use of zinc oxide or comparable zinc compounds. However, an additional restriction is advisable.
• the amount of the calibrating additive and in particular the amount of lime must be limited.
• the proposed maximum amount is set at about 2 Ib'bbl oil rinse after the aforementioned older applications have been disclosed.
• the oleophilic amine compounds can at the same time be used at least in part as an alkali reserve of the invert drilling fluid, but they can also be used in combination with conventional aicalire reserves, in particular together with lime.
• Preferred is the use of oleophilic amine compounds which are at least predominantly free of aromatic constituents.
• olefinically unsaturated aliphatic, cycloophatic and / or heterocyclic oleophilic basic amine compounds which contain one or more N groups which are capable of forming salts with carboxylic acids are particularly suitable.
• the water solubility at room temperature of these amine compounds is at most about 5% by weight. - And is expediently less than 1 wt .-%.
• Typical examples of such amine compounds are at least largely water-insoluble primary, secondary and / or tertiary amines, which can also be alkoxylated to a limited extent and / or substituted with, in particular, hydroxyl groups. Further examples are corresponding aminoamides and / or heterocycles containing nitrogen as a ring component. Suitable are, for example, basic amine compounds which have at least one long-chain hydrocarbon radical with preferably 8 to 36 carbon atoms, in particular with 10 to 24 carbon atoms, which can also be mono- or poly-olefinically unsaturated.
• the oleophilic basic amine compounds can be added to the drilling fluid in amounts of up to about 10 Ib / bbl, preferably in amounts of up to about 5 Ib / bbl and in particular in the range of about 0.1 to 2 Ib / bbl.
• the present invention is based on the object of further developing systems of the type concerned and in particular drilling fluids of high ecological compatibility.
• the invention intends to provide oils or oil mixtures for the construction of drilling fluids based on W / O emulsions which are technically usable and easily accessible and at the same time are distinguished by a high ecological value.
• the invention intends to make additives available for the above-described systems of the type concerned here, which give drilling fluids based on W / O emulsions valuable additional properties without adversely affecting their ecological compatibility.
• the technical solution to the problems according to the invention is based on the knowledge that selected alcohols which are adapted to the particular application can lead to new and improved drilling fluids of the type specified.
• the invention relates in a first embodiment to the use of a) at least largely water-insoluble and flowable and pumpable mono- and / or polyfunctional alcohols of natural and / or synthetic origin in the temperature range from 0 to 5 ° C. or of b) in the stated Temperature range of flowable and pumpable solutions of at least largely water-insoluble mono- and / or #functional alcohols of natural and / or synthetic origin in ecologically compatible water-insoluble oils as a closed oil phase of drilling fluids, which are present as a W / O emulsion, a disperse in the alcohol-containing oil phase have aqueous phase and, if desired, further conventional additives and are suitable for the environmentally friendly development of, for example, oil or natural gas deposits.
• the invention relates to invert drilling fluids of the type described, which are characterized in that they contain, as a closed oil phase or dissolved in ecologically compatible oils, an addition of at least largely water-insoluble mono- and / or polyfunctional alcohols, the respective oil phase in the temperature range from 0 to 5 ° C is flowable and pumpable and has flash points above 80 ° C.
• the closed oil phase of the invert drilling fluids is exclusively or largely formed by the essentially water-insoluble and preferably pronounced oleophilic alcohols. Understandably, the rheology of the alcohols used must be adapted to the technical requirements of the drilling fluids. Slight theological corrections are possible by using the small amounts of diluents provided in this embodiment.
• oil phases are particularly suitable, which are formed by more than 70% by weight, preferably by more than 80% by weight and, if desired, exclusively by the alcohols as such. The general specialist knowledge applies to the rheological requirements of such oils for the field of use of drilling fluids, which will be discussed again below.
• branched alcohols of the same C number range can represent usable flowable and pumpable oil phases in the sense of the invention.
• the range of low carbon numbers in particular the range of about C 0 , is particularly suitable, although here too the branched-chain alcohols can have rheological advantages.
• oil mixture components optionally used in small amounts in this embodiment can be pure, in particular aromatic-free hydrocarbon compounds, but in particular selected ester oils of the type described in the above-mentioned earlier applications by the applicant.
• a second embodiment of the invention accordingly relates to the use of oil phases in systems of the type in question which nevertheless contain considerable or even predominant amounts of non-water-miscible oils which are used in a mixture with the pronounced oleophilic alcohols provided according to the invention.
• the content of alcohols selected according to the invention is generally above 10% by weight to approximately 70% by weight, in each case based on the liquid oil phase, alcohol contents in amounts of at least approximately 35% by weight and preferably at least about 50 wt. - 5 , dr Oil phase can be preferred.
• the rheology of such systems is largely determined by the nature of the compounds used as mixture components. However, it will also be shown that the concomitant use of alcohols according to the invention can also have considerable practical importance for these embodiments.
• Mixture components for this second embodiment of the invention are, in turn, both pure, in particular aromatic-free, hydrocarbon oils and, above all, ester oils of the type described in the applicant's earlier applications. Mixtures of these types also fall within the scope of the invention, it being possible for both mixtures of ester oils with pure hydrocarbon compounds and mixtures of different types of ester oils to be mixture components for use together with the oleophilic alcohols.
• the pure hydrocarbon oils which have no functional groups are in the oil phase in amounts of at most 50% by weight, preferably at most about 35% by weight and in particular in amounts of at most about 25% by weight. % - in each case based on the oil phase. In the most important embodiments of the variant described here, mixtures of the alcohols and ester oils defined according to the invention are used as the oil phase without the addition of pure hydrocarbon compounds.
• the invention relates to the use of the practically water-insoluble alcohols with a particularly pronounced oleophilic character as an additive in the oil phase of drilling fluids based on W / O emulsions.
• the amount of the alcohols used according to the invention is usually in the range from about 0.1 to a maximum of 10% by weight, preferably in the range from about 1 to 5% by weight. -% of the oil phase.
• the circle of suitable water-insoluble alcohols can understandably expand substantially in this embodiment.
• the rheology of the overall system is no longer determined by the theological values of alcohol.
• important improvements in the behavior of drilling fluids of the type described above are achieved.
• the main component of the closed oil phase is formed exclusively or predominantly by ester oils of the type described in the above-mentioned earlier applications by the applicant.
• the main components for the oil phase are accordingly at least 25% by weight, preferably at least 50% by weight and in particular at least about 75 to 80% by weight of the oil phase as ester oil.
• pure hydrocarbon oils of the prior art can also be used, but this is expediently dispensed with entirely.
• the use of the alcohols as the oil phase but also their use as quantitative or subordinate ones Portion in the oil phase requires the sufficient water insolubility of these alcohol components.
• the water solubility of suitable alcohols is preferably below 5% by weight, in particular below 1% by weight, and preferably not more than about 0.5% by weight.
• Monofunctional and / or polyfunctional alcohols are suitable as long as the oleophilic character of the alcoholic component is preserved.
• difunctional compounds and / or partial ethers of polyfunctional alcohols with at least one free hydroxyl group are particularly suitable.
• the alcohols themselves should be ecologically compatible and, accordingly, in the preferred embodiment have no aromatic constituents.
• Straight-chain and / or branched aliphatic or also corresponding unsaturated, in particular mono- and / or poly-olefinically unsaturated alcohols are the preferred compounds. Cycloaliphatic alcohols can be considered.
• the free alcohols used according to the invention can be the same or different from the alcohol components used in the ester oil. While the alcohol component in the ester oils is determined, for example, by considerations regarding the rheology of the ester oil and / or the accessibility of the ester-forming alcohols, the use of the free alcohols according to the invention is based on the desired improvements in invert drilling fluid.
• the alcohols should flow and pump at low temperatures, in particular in the range from 0 to 5 ° C., or with the limited quantities ecologically compatible mixture components for the flowable phase to be liquefied.
• the solidification values of such oil phases should be below 0 C, preferably below - 5 ° C and in particular below - 10 C.
• the alcohols themselves should have flash points of at least 80 ° C., preferably at least 100 ° C. and in particular at least 120 ° C.
• Suitable polyols are, in particular, optionally branched-chain diols with a sufficient extent of the oleophilic hydrocarbon radical in the molecule.
• Suitable examples include m oleophilic diols with hydroxyl groups in the alpha, omega-position and / or diols that have hydroxyl groups on their adjacent carbon atoms.
• Typical examples of compounds of this type are 2, 2-dimethyl-1, 3-propanediol (neopentyl glycol) or
• water-insoluble alcohols are used which in turn are free from basic amino groups and preferably also contain no other reactive groups, for example carboxyl groups.
• Oil components suitable for blending within the scope of the invention are the mineral oils used in the practice of drilling fluids today, and preferably essentially aromatic-free aliphatic and / or cycloaliphatic hydrocarbon fractions of the required flow properties. Reference is made to the relevant state of the art in print and the commercial products on the market.
• flowable and pumpable esters of monofunctional alcohols with 2 to 12, in particular with 6 to 12 C atoms and aliphatic saturated monocarboxylic acids with 12 to 16 C atoms or their mixture with at most in the temperature range from 0 to 5 C. approximately the same amounts of other monocarboxylic acids are also used as the oil phase.
• ester oils which are at least about 60% by weight, based on the respective carboxylic acid mixture, of esters of aliphatic C.sub.1, monocarboxylic acids and, if desired, the remainder to minor amounts of shorter-chain aliphatic and / or longer-chain, then in particular 1- and / or poly-unsaturated monocarboxylic acids.
• Esters are preferably used which have a Brookfield (RVT) viscosity in the temperature range from 0 to 5 C in the range not above 50 mPas, preferably not above 40 mPas and in particular of at most about 30 mPas.
• the esters used in the drilling mud show solidification values (pour point and pour point) below - 10 ° C, preferably below - 15 ° C and in particular have flash points above 100 ° C, preferably above 150 ° C.
• the carboxylic acids present in the ester or ester mixture are straight-chain and / or branched and are of vegetable and / or synthetic origin. They can be derived from appropriate triglycerides such as coconut oil, palm kernel oil and / or babassu oil.
• the alcohol residues of the esters used are derived in particular from straight-chain and / or branched saturated alcohols having preferably 6 to 10 carbon atoms. These alcohol components can also be vegetable and / or animal Origin and thereby obtained by reductive hydrogenation of corresponding carboxylic acid esters.
• ester oils is derived from olefinically 1- and / or polyunsaturated monocarboxylic acids with 16 to 24 carbon atoms or their mixtures with subordinate amounts of other, in particular saturated monocarboxylic acids and monofunctional alcohols with preferably 6 to 12 carbon atoms . These ester oils are also flowable and pumpable in the temperature range from 0 to 5 ° C. Particularly suitable are esters of this type which are derived from more than 70% by weight, preferably more than 80% by weight and in particular more than 90% by weight of olefinically unsaturated carboxylic acids in the range from C, - .
• the solidification values are below - 10 C, preferably below - 15 C, while the flash points are above 100 ° C and preferably above 160 ° C.
• the esters used in the drilling mud show a Brookfield (RVT) viscosity of not more than 55 mPas, preferably not more than 45 mPas, in the temperature range from 0 to 5 ° C.
• the unsaturated C 1 g present in the ester is derived from not more than 35% by weight of 2- and poly-olefinically unsaturated acids, with at least about 60% by weight of the acid residues preferably being mono-olefinically unsaturated are.
• the C - g - ⁇ - monocarboxylic acids present in the ester mixture are derived from more than 45% by weight, preferably more than 55% by weight, from 2- and / or polyolefinically unsaturated acids. Saturated carboxylic acids of the range present in the ester mixture. g,.
• Saturated carboxylic acid esters are preferably in the range of lower C numbers for the acid residues.
• the present carboxylic acid residues can be of vegetable and / or animal origin. Vegetable starting materials are, for example, palm oil, peanut oil, castor oil and in particular rape oil.
• Carboxylic acids of animal origin are, in particular, corresponding mixtures of fish oils such as herring oil.
• esters of C, _-monocarboxylic acids and mono- and / or polyfunctional alcohols which are flowable at room temperature and have flash points above 80 ° C. Temperature range from 0 to 5 ° C are flowable and pumpable.
• esters of these lower carboxylic acids with monofunctional alcohols with at least 8 C atoms and / or esters of these acids with dihydric to tetravalent alcohols with preferably 2 to 6 C atoms are particularly suitable.
• acetic acid is particularly suitable as the ester-forming acid component of this class. Measures for rheology and volatility or.
• the solidification values of preferred esters of this subclass correspond to the values mentioned above.
• Suitable mixture components from this subclass are, in particular, esters of monofunctional alcohols of natural and / or synthetic origin, the chain length of which, when present, is predominantly aliphatic saturated alcohols in the range from C.sub.1, in the case of 1- and polyolefinically unsaturated alcohols, but also higher C numbers, for example up to about C 2 ". Details can be found in the applicant's older patent application P 39 07 391 .2 (D 8606).
• esters described in the parallel application P 39 07 392.0 (D8607) from monocarboxylic acids synthetic and / or natural origin with 6 to 11 carbon atoms and 1- and / or polyfunctional alcohols, which are preferably also flowable and pumpable in the temperature range from 0 to 5 ° C.
• Multi-component mixtures fall within the scope of the invention which, together with the alcohols defined according to the invention, can contain one or more of the mixture components listed in detail here.
• any mixes can be used, provided they meet the basic theological requirements for invert drilling fluids of the type concerned here.
• Examples of such multi-component mixtures include materials based on different types of ester oils or mixtures of substances additionally containing mineral oil.
• oleophilic basic amine compounds are used together with ester oils, which are described in detail in applicant's earlier application P 39 03 785.1 (D 8543) mentioned at the beginning. To Details are referred to the disclosure of this earlier application described above.
• ester oils are also used as mixture components in the context of the invention - and in particular ester oils based on carboxylic acids with at least 6 C atoms - are used, it may be expedient not to use significant amounts of highly hydrophilic bases of inorganic and / or organic in the oil rinse Way to use.
• Lime can be used effectively as an alkali reserve. However, it is then expedient to limit the maximum amount of lime to be used with about 2 lb / bbl, it being preferred to work with drilling mud loading on lime that is slightly below this, for example in the range from about 1 to 1.8 Ib / bbl (lime / drilling fluid).
• other known alkali reserves can be used.
• Invert drilling muds of the type concerned here usually contain, together with the closed oil phase, the finely disperse aqueous phase in amounts of about 5 to 45% by weight and preferably in amounts of about 5 to 25% by weight.
• the range of about 10 to 25 wt. - Disperse aqueous phase can be of particular importance.
• Emulsifiers that can be used in practice are systems that are suitable for forming the required W / O emulsions.
• Selected oleophilic fatty acid salts for example those based on amidoamine compounds, are particularly suitable. Examples of this are described in the already cited US Pat. No. 4,374,737 and the literature cited therein.
• a particularly suitable type of emulsifier is the product sold by NL Baroid under the trade name "EZ-mul".
• Emulsifiers of the type concerned here are sold commercially as highly concentrated active substance preparations and can be used, for example, in amounts of about 2.5 to 5% by weight, in particular in amounts of about 3 to 4% by weight, based in each case on the oil phase, are used.
• hydrophobicized lignite is used in particular as a fluid loss additive and thus in particular to form a dense covering of the drilling walls with a largely liquid-impermeable film.
• Suitable amounts are, for example, in the range from about 15 to 20 lb / bbl or in the range from about 5 to 7% by weight, based on the oil phase.
• the viscosity former usually used is a cationically modified, finely divided bentonite, which can be used in particular in amounts of about 8 to 10 lb / bbl or in the range of about 2 to 4% by weight, based on the oil phase.
• the weighting agent usually used in the relevant practice for setting the required pressure equalization is barite, the additional amounts of which are adapted to the respectively expected conditions of the bore. For example, by adding barite it is possible to increase the specific weight of the drilling fluid to values in the range up to approximately 2.5 and preferably in the range from approximately 1.3 to 1.6.
• the disperse aqueous phase is loaded with soluble salts in invert drilling fluids of the type concerned here.
• Calcium chloride and / or potassium chloride are predominantly used here, the saturation of the aqueous phase at room temperature with the soluble salt being preferred.
• emulsifiers or emulsifier systems may also serve to improve the oil wettability of the inorganic weighting materials.
• further examples are alkylbenzenesulfonates and imidazoline compounds. Additional Information on the relevant prior art can be found in the following references: GB 2 158 437, EP 229 912 and DE 32 47 123.
• invert rinses based on selected alcohols or on the basis of alcohol mixtures are used with an oil / water ratio of 80/20 in the following basic formulation:
• organophilic bentonite (Geltone I I from NL Baroid)
• the invert drilling fluid is then aged for 16 hours at 125 ° C. in an autoclave in a “roller oven” in order to check the influence of temperature on the stability of the emulsion. Then the viscosity values at 50 C are determined again.
• oil phases used in these examples - i. H. are the following:
• Example 1 Synthetic oxo alcohol of chain length C 1 Q (handicraft product “Etoxo C 10")
• Example 2 100 ml of the synthetic alcohol from Example 1 in admixture with 100 ml of a C "alcohol mixture of natural origin (commercial product" Lorol 810 "from the applicant)
• Example 3 100 ml of the alcohol according to Example 1 in admixture with 100 ml of a C.-, - alcohol mixture of natural origin (commercial product "Lorol technically” from the applicant)
• This rinsing formulation does not include the use of a W / O emulsifier.
• the following alcohols or alcohol / ester oil mixtures are used in detail in these examples 5 to 8.
• Example 5 C_ .. alcohol cut of natural origin (commercial product "Lorol 810" of the applicant)
• Example 6 A mixture of 102 ml of the alcohol according to Example 5 and 98 ml of isobutyl oleate
• organophilic lignite (Duratone" from NL Baroid)
• An undistilled isobutyl rapeseed oil ester is used as the ester oil, which is based on a mixture of predominantly unsaturated straight-chain carboxylic acids which correspond approximately to the following distribution: 60% oleic acid, 2% linoleic acid, 9 to 10% linolenic acid, olefinically unsaturated C_. --- Monocarboxylic acids about 4%, the rest saturated monocarboxylic acids predominantly in the C. range. , .. -. This beet cholesterol also has the following characteristics:
• the Rübolester / Lorol 810 mixing ratios are selected as follows and shifted in the direction of increasing Lorol 810 content:
• Example 9 170 ml ester oil / 30 ml alcohol schnapps
• Example 10 150 ml ester oil / 50 ml alcohol cut
• Example 11 120 ml ester oil / 80 ml alcohol cut
• Example 12 100 ml ester oil / 100 ml alcohol cut
• the viscosity values determined in each case on unaged and aged drilling fluids are the following:
• drilling fluids of the following formulation are used:
• Example 13 Addition of 2 g docosanol, i.e. H. of a linear C __ alkanol
• Example 14 Addition of 5 g of an EO / PO addition product to C._, a -alcohol cut of natural origin (commercial product “Lorol technically” from the applicant) of the following composition: C.-, 8 -alcohol cut / 3 EO / 6 PO (commercial product "Dehyton LT 36" from the applicant)
• Example 15 Addition of 5 g of an EO / PO polyalkylene glycol with an average molecular weight of about 2000 (commercial product "Dehydran 240")
• Example 16 Addition of 2 g of 2,2-dimethyl-1,3-propane-diol (neopentyl glycol)
• the viscosity values and additionally the fluid loss value are determined on the respective oil rinses of Examples 13 to 16 and in the comparative example using the HTHP method.
• For the determination of the HTHP fluid loss value see the mentioned manual from N L Baroid, London “Manual of drilling fluids technology”, subchapter “Oil mud technology”, chapter PROPERTIES AND TESTING PROCEDURES "HTHP-filtrate”.

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• 1989
  • 1989-04-07 DE DE3911238A patent/DE3911238A1/de not_active Withdrawn
• 1990
  • 1990-03-29 US US08/054,462 patent/US5348938A/en not_active Expired - Lifetime
  • 1990-03-29 WO PCT/EP1990/000499 patent/WO1990012070A1/de not_active Application Discontinuation
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• 1991
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