NL8204996A - FLUID COMPOSITIONS FOR FINISHING DRILL WELLS. - Google Patents

Description

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Fluid compositions for drilling down wells

The invention relates to wellbore and wellbore fluid compositions and in particular to high density borehole or borehole fluid compositions which can be used in petroleum finning without causing excessive corrosion of pipes or tubes of iron or ferrous alloys with which the composition may come into contact.

Current practice in surveying wells such as oil and gas fin wells is that a drilling fluid such as mud, salt water, water or oil is introduced into the well casing and the casing is perforated using a spherical charge, either by chemical means or with a punch-15 type perforator. If the pressure in the formation passing through the well is greater than the hydrostatic pressure of the oil or water column at the well level, it is customary to use a composition with a sufficiently coarse density so that the hydrostatic pressure thereof pressure of the formation exceeds to control the well during perforation of the move and other routine routing or restoring operations.

These compositions are prepared by dissolving certain inorganic salts in water.

Those compositions which are used in repelling and restoration enhancements have certain undesirable properties. For example, those compositions are usually somewhat corrosive and consequently cause corrosion of the ferrous metal conduits with which the composition comes into contact. This problem is especially acute in petroleum recovery operations requiring a high density composition because the increased concentration of salts in the liquid composition results in greater corrosion damage to the ferrous metal pipes.

For various reasons, it has become common in the petroleum industry to drill ever deeper wells and often to explore those wells in multiple zones.

This, of course, has brought further new, unique problems in the technique of finishing and putting wells into use.

Also the closely related problems of well repair have become much greater due to the advent of, and in particular, the multiple finish of wells which are at least in part a result of previous finishing factors. For example, after finishing an oil well, to put that well into production, a finishing fluid is again used to fill the annular space between casing 15 and the pump tube or riser above the packers, and this fluid is used throughout the life of the well. well or until further well treatment is needed, left there.

The purpose of using such liquids to fill the annular space between the pump tube and the casing above the packer after a well has been completed and is in production is to maintain hydrostatic pressure at the top of the packer . The pressure desired at such a point is only slightly greater than the highest pressure of all producing formations. In this way, the hydrocarbons that are recovered exert only slightly less pressure on the underside of the packer than the finishing liquid exerts on the top of the packer. By reducing the pressure differential between the top and bottom of the packer in this way, the crude oil or other fluids exiting the formation will not leak out along the packer and / or the well control and control of the well will not be lost .

The disadvantages and harmful consequences of the leakage of such fluids along the packers are well known. The consequences of losing control of or control over a well are even better known. Likewise, and especially with regard to 8204996 r 3 the multiple finishing of "wells", the consequences of a delivery fluid that is corrosive to ferrous metals are generally known and recognized by those skilled in the art.

When drilling ever deeper wells in search of petroleum-producing formations, the temperatures encountered become higher and higher, encountering difficulties that did not previously exist. In oil and gas wells, temperatures of the order of 93 to 121 ° C or even higher can be encountered. At those temperatures, the finishing fluids can form corrosive fluids which will damage the ferrous metal pipes and tubes with which they come into contact.

It is therefore desirable to provide a wellbore finishing fluid which will not be corrosive to ferrous metal pipes with which it may come into contact.

15 As a rule, the temperature literally increases with depth. Many factors influencing the temperature can vary in subsurface locations, and the subsurface temperatures can differ considerably even in relatively close locations. The occurrence of this and the reasons for it are generally known in this branch of the art. Thus, despite the general rule that the temperature increases with the depth, sometimes it is encountered at a relatively shallow depth, for example at 900 m, already at high temperatures. Without exception, high temperatures are found at depths of approximately 1 * 575 m, regardless of the location. High temperatures can thus be encountered at a depth below 900 m. These temperatures, regardless of the depth at which they are found, increase or accelerate the drawbacks of the prior art finishing and packer liquids.

In an attempt to overcome the above problems, saline solutions and high density for use as wellbore fluids have been proposed. For example, U.S. Patent 3,126,950 discloses a finishing and packing liquid consisting of a water solution of calcium chloride and zinc chloride and optionally an 8204996 * k corrosion inhibitor. U.S. Patent U.292,183 discloses a high density liquid composition consisting of zinc bromide and calcium bromide in water, which composition has a density in the range of about 1.7 to 2.16 kg / l and a pH in the range from 3.5 to 6.0.

These high density fluid compositions have only limited utility in their use, severe downhole corrosion problems and corrosion of aboveground equipment have occurred.

The present invention now solves or at least alleviates the above-mentioned problems. According to the invention, a new wellbore composition is provided and a method of using that composition.

Described in the most general form and the invention relates to a composition for use as a wellbore medium, wellbore packing and for use in wellbore perforating, comprising water, one or more of the salts aluminum chloride, aluminum bromide Aluminum iodide, ammonium chloride, ammonium bromide, ammonium iodide, sodium chloride, sodium bromide, sodium iodide, potassium iodide, potassium bromide, potassium chloride, calcium chloride, calcium bromide, calcium iodide, zinc chloride, zinc bromide and zinc iodide and one or more acetylene alcohols having a general formula 1, H, an alkyl, phenyl, substituted phenyl or hydroxyalkyl group, which composition has a density of from about 1 to about 2.6 kg / l of composition. Optionally, other ingredients can be added to the above composition. For example, mono-, di-, or trialkylamines having about 2 to about 6 carbon atoms in each alkyl radical, heterocyclic amines having a six-membered ring, quinolines, and quaternized derivatives of quinolines, quaternized pyridines, alkylpyridines having 1 to 5 alkyl substituents on the ring per pyridine residue in which the alkyl-35 substituents contain 1 to 12 carbon atoms and mixtures thereof can be added.

8204996 t 5

If desired, one or more of the acids can be added formic acid, acetic acid, propionic acid, butyric acid, glyoleic acid mixtures thereof to the above composition. The method of the invention comprises contacting the well under a sufficient hydrostatic pressure with the composition of the invention.

When the above-described wellbore finishing or repair method is used, the composition is relatively non-corrosive to the ferrous metal pipes with which it comes into contact.

The salts that can be used in the practice of the present invention function as density enhancers and enhance the corrosion inhibiting action. These salts are summarized in the following table:

Table A

Salts suitable as a density reducing agent

Name Formula type weight aluminum bromide AlBr ^ 3.01 aluminum chloride AlCl ^ 2tkk 20 aluminum iodide All ^ 3.98 ammonium bromide NH ^ Br 2.33 ammonium chloride NH ^ Cl 1.53 ammonium iodide NH ^ I 2.51 calcium bromide CaBr2 3.35 25 calcium chloride CaCl2 2.15 calcium iodide Calg 3.96 potassium bromide KBr 2.75 potassium chloride KC1 1.98 potassium iodide KI 3.13 30 sodium bromide NaBr 3.20 sodium chloride NaCl 2.16 sodium iodide Na 3.67 zinc bromide ZnBr ^ 2.56 zinc chloride ZnCl ^ 2, 91 35 zinc iodide Znl2 U, 66 8204996 6

The preferred salts and combinations of salts for use in the invention are sodium chloride, calcium chloride, calcium bromide and the following combinations of salts: sodium chloride with calcium chloride, calcium chloride with calcium bromide, calcium chloride with zinc chloride, calcium bromide with zinc bromide, calcium bromide, zinc bromide and zinc chloride and zinc chloride with zinc bromide.

The particularly preferred salts and combinations of salts for use in the invention are calcium chloride, calcium chloride with calcium bromide, calcium bromide with zinc chloride and calcium bromide with zinc bromide.

These salts are used in the composition of the invention in an amount as necessary to achieve a composition with a density of about 1.0 to 2.6 kg / l of the composition.

The acetylene alcohols which inhibit ferrous metal corrosion and which can be used according to the invention have the general formula 1, wherein R represents H, 20 an alkyl, phenyl, substituted phenyl or hydroxyalkyl group.

Examples of suitable acetylene compounds include methyl butynol, ethyl octynol, methyl pentynol, 3,1-dihydroxy-1-butyne, 1-ethynylcyclohexanol, 3-methyl-1-nonyn-3-ol, 2-methyl-3-butyne-2-ol, and also 1-propyn-3 "ol, 1-butyn-3" ol, 1-pentyn-3-ol, 1-heptyn-3-ol, 1-octyn-3-ol, 1-nonyl-3-ol, 1-decyn-3-ol, 3- (2, U, 6-trimethyl-3-cyclohexenyl) -1-propyn-3-ol.

In many cases, the corrosion-protecting effect of the composition of the invention can be enhanced by adding an organic amine to the above-mentioned acetylene alcohol. Amines suitable for this purpose include

mono-, di- and trialkylamines with about 2 to about 6 carbon atoms in each alkyl radical, heterocyclic amines with an N-containing six-ring, quinolines and quaternized derivatives of quinolines, alkylpyridine with 0-6 alkyl substituents in the ring per pyridine residue the alkyl substituents 1-12 contain carbon atoms and mixtures thereof. Examples of these amines include ethylamine, diethylamine, triethylamine, propylamine, dipropylamine, tripropylamine, mono-, di-, tributylamine, mono-, di- and tripentylamine, mono-, di- and trihexylamine and isomers thereof, such as isopropylamine, tertiary butylamine, aniline, dehydroabiethylamine, pyridine, quaternized derivatives of pyridine, nitropicoline, methyl-quinoline alkylpyridines such as alkyl pyridines with 1 to 5 alkyl substituents in the ring per pyridine residue, quinolines, quatemized derivatives of quinolines, alkyl quinolines and mixtures thereof.

In some cases it may be desirable to include an acid in the composition of the invention. The acid optionally included in the composition of the invention will remove acid-soluble calcareous deposits in the borehole or open perforations in the borehole.

If an acid is desired, suitable acids that can be used include formic acid, glycolic acid, acetic acid, propionic acid, butyric acid mixtures thereof.

As mentioned earlier, the acetylene alcohol can only be used in the composition according to the invention or an organic amine can be combined with an acetylene alcohol. The relative ratio of acetylene alcohol and organic amine can vary over a wide range. Furthermore, it has been found that the concentration of acetylene alcohol and the concentration of the organic amines are not interdependent and thus a significant improvement in corrosion protection can be obtained by varying the concentration of one of the components without varying that of the others. .

Generally, the concentration of acetylene alcohol will range from about 0.2 to about 5.0 vol. of the composition. However, lower or higher concentrations are still effective when an organic amine is added to the composition of the invention. For example, the amine concentration will vary over a wide range with no true upper or lower limits 8204996-8. Generally, the organic amine concentration, if desired, will range from about 0.05 to 3.0% by volume of the composition of the invention. A particularly effective mixture containing an amine and acetylene alcohol is mentioned below.

Mixture I

Chemical compound: vol. # Pure propargyl alcohol —--------------- 33.9 ^ crude propargyl alcohol --------------- 11.31 et al. hylo cty nol --———---------------------- 16,97 pyridines with high content of alkyl substituents 3.85 formaldehyde (55%) in methanol ------------ 33.9 * +

Another effective composition containing an amine 15 and acetylene alcohol is the following:

Mixture II

Chemical compound: vol. % pure propargyl alcohol ------------------ 33.9 * + crude propargyl alcohol ------------ 11.31 20 ethyl octynol ----- -------------------------- 16.97 alkylpyridines ------------------- --------- 3.85 diacetone alcohol ——————-----— ----- 33.9 * +

Another effective mixture containing an amine and acetylene alcohol is listed below. This mixture is very effective if the density of the composition according to the invention is between about 1.8 and 2.0 kg / l and the salts used are calcium bromide and zinc chloride and if the density is between about 2.0 kg / l and about 2.3 kg / l and the salts used are calcium bromide and zinc bromide, 8204996 - 9 -

Mixture III

Chemical compound: vol. # Crude quattrified quinoline————---- 56.00 propargyl alcohol-— ---------------- 21.00 5 ethyl octynol ------ ------------------ 13.00 adduct of nonylphenol with 15 nol ethylene oxide --- 10.00 ----- 0.021+ g / ml of the compositions

The density of the composition according to the invention is preferably between about 2 and 2.6 kg / 1 composition.

The concentration of the acid when used in the composition according to the invention can vary over a wide range. Generally, the amount of acid when used is 0.2 vol. To about 1 + 0 vol. # Based on the composition. The particularly preferred acid concentration is about 3 to about 17 vol. # Of the composition.

The following examples more fully illustrate the principles of the invention, involving specific compounds and conditions, but do not limit the invention in any way.

Example I

To compare the corrosion inhibiting ability of the composition of the invention, a number of samples were prepared containing 10 vol. # Formic acid or acetic acid along with varying amounts of calcium chloride. Test mixtures 1 to 5 contain mixture I as an inhibitor. Mixture I, as previously mentioned, contains the following ingredients: pure propargyl alcohol, crude propargyl alcohol, ethyl octynol, pyridines with high content of alkyl substituents and formaldehyde (55 #) in methanol.

Test mixtures 6 to 10 contain, as inhibitor, mixture III. Mixture III consists of crude quattrified quinoline, propargyl alcohol, ethyl octynol and adduct of nonyl phenol with 15 moles of ethylene oxide, as well as CuCl 4.

A steel plate of API type N-80 was placed in the acidic composition 8204996-10 for a period of 8 hours at 93 ° C. All tests were conducted under atmospheric conditions. The weight loss was converted m kg / m.

The results of these tests are shown in Table B.

Table B

5 ratio of volume solution to surface plate 3.875 ml / cm 2 o corrosion loss kg / m test inhibitor CaCl formyl acid acetyl acid 1 mixture I - 6.866 7.081 10 2 "I 1.1k kg / 1 1.2k 0.69k 3" I 1.2 kg / 1 0.550 0.598 k "I 1.26 kg / 1 0.120 0.120 5" I 1.32 kg / 1 0.120 0.096 6 "III - 0.69k 0.85 55 7 7 UI 1, I kg / 1 0.215 0.311 8 "III 1.2 kg / 1 0.072 0.215 9" III 1.26 kg / 1 0.072 0.0k8 10 "III 1.32 kg / 1 0.Qk8 0.0k8

Table B shows that the compositions of the invention effectively reduce iron corrosion. Example II

In order to demonstrate the corrosion inhibiting ability of the compositions of the invention, several samples of a 10 vol. 2 acetic acid solution containing 25 different salts were prepared. The density of the samples was 1.2 kg / l. Test mixtures k to 6 and 8 contain mixture I as an inhibitor. The composition of this mixture was the same as in Example I. MBA 29 was used as inhibitor in test mixtures 1 to 3 and 7.

30 MBA 29 contained 50 vol. As components; crude quaternized quinoline and 50% by volume methylbutynol.

A plate of API type N-80 steel was placed in one of the acid mixtures at 93 ° C for 6 h.

All tests were performed under atmospheric conditions. The corrosion loss was converted into kg / m.

8204996 - 11 -

Table C shows that these compositions of the invention reduced iron corrosion.

Table C

o volume - area ratio ~ 3,875 ml / cm 5 inhibitor corrosion loss test salt 1 vol. 3 »_kg / nr_ 1 A1C13 MBA29 0.020 2 NaBr MBA29 0.020 3 HHj ^ I MBA29 0.015

10 U AlCl 2 mixture I 0.0M

5 NaBr mixture I 0.088

6 NH2 I mixture I 0.02U

7 - MBA29 0J3k '

8 - mixture I 1, UoU

Example III

In order to compare the corrosion inhibiting ability of the compositions of the invention, a composition was prepared with a density of 2.3 kg / l. The salt used in the composition contains a mixture of zinc bromide and calcium bromide. A sheet of steel API type N-80 was placed in the mixture held at 127 ° C for 7 days. All tests were conducted under atmospheric conditions.

Inhibitor Blend III consisted of the same components as described in Example 1. Inhibitor Blend II was composed of pure propargyl alcohol, crude propargyl alcohol, ethyl octynol, alkyl pyridines, and diacetone alcohol.

Run 9 could not be accurately calculated due to sample contamination during the run.

The results of these tests are shown in Table D.

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Table D

2 volume - area ratio 3,873 ml / and inhibitor corrosion verity test 1 vol # kg / m ^ 1 - 0,1 * 99

2 propargyl alcohol 0.28U

3 methyl butynol 0.093 h methyl pentynol 0.27 ** 5.50 vol. # hexynol 0.127 6 ethyl octynol and 10 vol. # of nonylphenol with 15 moles ethylene oxide 0.1 * 79 7 50 vol. # propargyl alcohol & 50 vol. # quaternized quinoline 0.061 * 8 50 vol. # methylbutynol & 50 vol. # quaternized quinoline 0 .05 ** 9 50 vol. # Methylpentynol & 50 vol. # Quaternized quinoline 0.51 ** 10 50 vol. # Propargyl alcohol Sc 50 vol. # Pyridine 0.215 11 mixture of an acetylene alcohol, cyclic amine and linear amines 0.25 ** 12 mixture of an acetylene alcohol, cyclic amine and linear amines 0.21 * 5 13 mixture of an acetylene alcohol, cyclic amine and linear amines 0.235 1U mixture of an acetylene alcohol, cyclic amine and linear amines 0.235 15 mixture II 0.02l *

16 mixture III 0.03U

Table D shows that the compositions of the invention effectively reduced iron corrosion.

In the examples, certain embodiments of the invention have been described for illustrative purposes; however, the invention is not limited thereto. A variety of modifications and variations of the compositions of the invention are possible without departing from the scope of the invention.

8204996

Claims (19)

A composition for use in drilling and repairing wells, characterized in that it comprises: (a) water (b) one or more of the salts aluminum chloride, aluminum bromide, aluminum iodide, ammonium chloride, ammonium bromide, ammonium iodide, sodium chloride, sodium bromide, sodium iodide, potassium bromide, potassium chloride, potassium iodide, calcium chloride, calcium bromide, calcium iodide, zinc chloride, zinc bromide, zinc iodide and mixtures thereof, and (c) one or more acetylene alcohols of the general formula 1, wherein R represents H, or alkyl, phenyl, substituted phenyl or hydroxyalkyl groups, such that the composition has a density of about 15. to 2.6 kg / l. Composition according to claim 1, characterized in that it contains one or more mono-, di- and / or tri-alkyl amines with 2 to 6 carbon atoms in each alkyl radical, heterocyclic amines with an N-containing 6-ring, quinolines and chatter - 20 derivatives of quinolines, quaternized derivatives of pyridines, alkyl pyridines with 1 to 5 alkyl substituents in the core per pyridine residue, the alkyl substituents having 1 to 12 carbon atoms or mixtures thereof. 3. A composition according to claim 1 or 2, characterized in that it further contains one or more of the acids formic acid, acetic acid, propionic acid, butyric acid, glycolic acid and / or mixtures thereof, said acid being present in an amount of about 0 , 2 to about Uo vol./S calculated on the composition. Composition according to claim 1, 2 or 3, characterized in that the salt in the composition is calcium chloride. Composition according to claim 2 - U, characterized in that it contains a pyridine and / or quinoline. 8204996 ψ - 1¼ - Composition according to claims 3 to 5, characterized in that it contains acetic acid. A composition according to any one of the preceding claims, characterized in that the composition has a density of about 2 to 2.6 kg / l. 8. A composition according to any one of the preceding claims, characterized in that it contains, as acetylene alcohol, methyl butynol, ethyl octynol, methyl pentynol, 3'-dihydroxy-1-butyne, 1-ethynylcyclohexanol, 3 "methyl-1-nonyn-3" ol, 2-methyl-3-butyn-2-ol, 1-propyn-3-ol, 1-butyn-3 "ol, 1-pentyn-3" ol, 1-heptyn-e-ol, 1-octyn-3_ol , 1-nonyl-3-ol, 1-decyn-3 "ol, 3 ~ (2.h.6-trimethyl-3" cyclohexenyl) -1-propyn-3 "ol and / or mixtures thereof. 9. A composition according to any one of the preceding claims, characterized in that the amount of acetylene alcohol in the composition is between 0.2 and 5.0% by volume, based on the composition. 10. Method of finishing a wellbore passing through an underground formation, characterized in that the well is contacted with a composition comprising (a) water under sufficient hydrostatic pressure to control the well (b) one or more of the salts of aluminum chloride, aluminum bromide, aluminum iodide, ammonium chloride, ammonium bromide, ammonium iodide, sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, calcium chloride, calcium bromide, calcium iodide, zinc chloride, zinc bromide or zinc iodide mixtures thereof and (c) one or more acetylene alcohols of the general formula 1 wherein R represents H, alkyl, phenyl, substituted phenyl or hydroxyalkyl groups, such that the composition has a density of about 1 to 2.6 kg / 1. 11. A method according to claim 10, characterized in that the composition further comprises one or more mono-, di- 8204996 - 15 - ....... '. ............... and / or trialkylamines of about 2 to 6 carbon atoms in each alkyl radical, heterocyclic amines with an N-containing 6-ring, quinolines and quinolines derivatives of quinolines, quaternized pyridines derivatives, alkyl pyridines 5 having 1 to 5 ring alkyl substituents per pyridine moiety wherein the alkyl substituents have 1 to 12 carbon atoms and / or mixtures thereof. 12. A method according to claim 10 or 11, characterized in that the composition further contains one or more of the 10 acids formic acid, acetic acid, glycolic acid, propionic acid, butyric acid and / or mixtures thereof, which mixture is present in the composition in an amount of about 0.2 to about kO% by volume calculated on the composition. A method according to claims 10-12, 15, characterized in that the salt in the composition is calcium chloride. 1U. Process according to claims 11-13, characterized in that the composition contains as amine pyridines and / or m quinolines. 15. Method according to claim 10 - 1U, characterized in that the composition contains acetic acid. A method according to claims 10-15, characterized in that the composition has a density of about 2 to 2.6 kg / l. 17. A method according to any one of claims 10-16, characterized in that the acetylene alcohol or alcohols is (are) present in an amount of 0.2 to 5% by volume. calculated on the composition. Process according to any one of claims 10 to 17, 30, characterized in that the composition as acetylene alcohol contains methyl butynol, ethyl octynol, methyl pentynol, 3-dehydroxy-1-butyne, 1-ethynylcyclohexanol, 3 "methyl-1-nonyne- 3 ~ ol, 2-methyl-3 "butyn-2-ol, 1-propyn-3 ~ ol, 1-butyn-3 ~ ol, 1-pentyn-3" ol, 1-heptyn-3 ~ ol, 1- octyn-3 "ol, 1-nonyl-3-ol, 35 1-decyn-3-ol, 3" (2,6-trimethyl-3-cyclohexenyl) -1-propyn-3-ol 8204996 - 16 - / / or mixtures thereof. 19 · Method for inhibiting the corrosion of a ferrous surface and in contact with an aqueous salt-containing liquid, which liquid is one or more of the 5 salts aluminum chloride, aluminum bromide, aluminum iodide, ammonium chloride, ammonium bromide, ammonium iodide, sodium chloride, sodium bromide, sodium iodide , potassium chloride, potassium bromide, potassium iodide, calcium chloride, calcium bromide, calcium iodide, zinc chloride, zinc bromide and / or zinc iodide 10, characterized in that the composition comprises one or more acetylene alcohols of the formula 1 wherein R represents H alkyl, phenyl, substituted phenyl or hydroxyalkyl groups, the liquid having a density of about 1 to 2.6 kg / l. 20. Process according to claim 19, characterized in that the liquid also contains one or more mono-, di- and / or tri-alkyl amines with 2 to 6 carbon atoms in each alkyl radical, heterocyclic amines having an N- ring, quinolines and quaternized derivatives of quinolines, alkyl pyridines having 1 to 5 alkyl substituents in the core per pyridine residue, the alkyl substituents having 1 to 12 carbon atoms and / or mixtures thereof. 21. Process according to claim 19 or 20, 25, characterized in that the aqueous liquid as salt contains calcium chloride. Process according to claims 19-21, characterized in that pyridines and / or quinolines are included in the composition as organic amines. A process according to any one of claims 19-22, characterized in that an amount of acetylene alcohol is included in the liquid such that the amount of acetylene alcohol in the final composition is about 0.2 to 5.0 vol. 35 2h. Process according to any one of claims 19, 23, 8204996 - 17 - * .................., characterized in that one or more of the following acetylene alcohols are included in the liquid: methylbutynol, ethyloctynol, methylpeatynol, 3.1+ "dehydroxy 1-butyne, 1-ethynylcyclohexanol, 3" methyl-1 * nonyn-3 "Ol, 2-methyl-3" butyne-2-ol, 1-propyne-3 ~ ol, 1-butyn-3-ol, 1-pentyn-3 ”ol, 1-heptyn-3-ol, 1 ~ octyn-3 ~ ol, l-nonyl-3-ol, 1-decyn-3 ~ ol, 3 "(2.4,6-trimethyl-2-cyclohexenyl) -1-propyn- * 3-ol and / or mixtures thereof. 8204996