CA2009732A1 - Process for stimulating oil and gas wells in oil and gas production from subterranean formations, and stimulant for this purpose - Google Patents
Process for stimulating oil and gas wells in oil and gas production from subterranean formations, and stimulant for this purposeInfo
- Publication number
- CA2009732A1 CA2009732A1 CA002009732A CA2009732A CA2009732A1 CA 2009732 A1 CA2009732 A1 CA 2009732A1 CA 002009732 A CA002009732 A CA 002009732A CA 2009732 A CA2009732 A CA 2009732A CA 2009732 A1 CA2009732 A1 CA 2009732A1
- Authority
- CA
- Canada
- Prior art keywords
- stimulant
- glycol ether
- ethylene oxide
- carbon atoms
- moiety
- 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
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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
- C09K8/58—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids
- C09K8/584—Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids characterised by the use of specific surfactants
Abstract
Abstract of the disclosure A process for stimulating oil and gas wells in oil and gas production from subterranean formations, and stimulant for this purpose In the process described, the oil/gas-containing sub-terranean formations are contacted with a selected fluorosurfactant as a stimulant. A particularly pre-ferred stimulant is composed essentially of the said fluorosurfactants and of non-fluorinated nonionic sur-factants from the group comprising the alkoxypolyethylene glycol ethers and from the group comprising the alkyl-phenoxypolyethylene glycol ethers, the three components being present in a weight ratio of preferably about 1 :
1 : 1.
1 : 1.
Description
X~ 3~3~3~
HOECHST A~TIENGESELLSC~T HOE 89/F 900 Dr. GL/nu Gendorf Work6 Process for stimulating oil and gas well~ in oil and gas production from subterranean formation~, and ~timulant for this purpose Description The invention relates to a proces~ for stimulating oil and ~as wells in oil and gas production from subterranean formations, the oil/gas-containing formation being contacted in the region of the well with a stimulant from the group comprising the fluorosurfactants. The inven-tion also relates to a stimulant.
The reduced production and the pressure decline in oil and gas production wells can have various ca~e~.
Deposits of organic substances such as asphaltenes, waxes and paraffins, inor~anic precipitates, swelling clay minerals or moving ~and grains, can reduce the perme-.
ability of the reservoir, in particular in the region of the well. The damage to the oil/gas-bearing formation can also be caused: by retained componen~s of, for ex-ample, mud fluids, which haYe made the capillaries in the pore space of the for~ation imperviou~.
It is known that stimulating fluids are used for over-coming this problem, which increa~e again the perme-ability of the reservoir, in particular in thesurroundings of the production and in~ection wells.
These fluids contain surface-active compounds which reduce the interfacial:tension at the pha~e boundaries and favorably~ affect the wetking p~opertie~ of the reservoir rock. ~ost recently, fluorine-containing surfactants have above all been recommended as surface-active compounds (stimulants). ~h~s, in US Patent~
4,425,242, 4,460,791 and 4,594,200, fluorosurfactants having a relatively long polyalkylene glycol ether group :
HOECHST A~TIENGESELLSC~T HOE 89/F 900 Dr. GL/nu Gendorf Work6 Process for stimulating oil and gas well~ in oil and gas production from subterranean formation~, and ~timulant for this purpose Description The invention relates to a proces~ for stimulating oil and ~as wells in oil and gas production from subterranean formations, the oil/gas-containing formation being contacted in the region of the well with a stimulant from the group comprising the fluorosurfactants. The inven-tion also relates to a stimulant.
The reduced production and the pressure decline in oil and gas production wells can have various ca~e~.
Deposits of organic substances such as asphaltenes, waxes and paraffins, inor~anic precipitates, swelling clay minerals or moving ~and grains, can reduce the perme-.
ability of the reservoir, in particular in the region of the well. The damage to the oil/gas-bearing formation can also be caused: by retained componen~s of, for ex-ample, mud fluids, which haYe made the capillaries in the pore space of the for~ation imperviou~.
It is known that stimulating fluids are used for over-coming this problem, which increa~e again the perme-ability of the reservoir, in particular in thesurroundings of the production and in~ection wells.
These fluids contain surface-active compounds which reduce the interfacial:tension at the pha~e boundaries and favorably~ affect the wetking p~opertie~ of the reservoir rock. ~ost recently, fluorine-containing surfactants have above all been recommended as surface-active compounds (stimulants). ~h~s, in US Patent~
4,425,242, 4,460,791 and 4,594,200, fluorosurfactants having a relatively long polyalkylene glycol ether group :
- 2 ~ t3~
in ~he molecule are de~cribed as a stimulating agent which is introduced into the subterranean formation to be treated.
The rçduction in the abovementioned interfacial tension values, achieved by mean~ of the known fluoro~urfactanks, still leaves something to be desired. The effectivene~s of the fluorosurfactants is also xeduced to a greater or lesser extent by adsorption losse~ during con~acting with the formation which i~ to be treated. There is thus ~0 still a demand for suitable and highly effective fluoro-surfactants for the purpose in guestion.
To meet this demand, it has been found that fluoro-surfactants with a very narrow range with xespect to the carbon atoms in the perfluoroalkyl radical and with the specific qroup -N(CH2CH2OH)2 in the mole~ule are advan-tageous and unexpectedly effective stimulants for the treatment of the formation~ in question.
The proces~ according to the invention for stLmulating oil and ga~ wells in oil and gas production from sub-terranean formation~, the oil/gas-containing formation being contacted in the region of the well with a stimu-lant from the group comprising the fluorosurfactants, comprises using as the stimulant at least ona fluoro-surfactant of the following formulae (1) to ~3), F~-CF=CHCH2N(C2H4H) 2 ( 1 ) R'f-CONHC3~6N(C2H4H)2 (2) R~y~CONHC3H6~(c2H4O~)2 (3~
o in which Rf, R~r and R"~ are a perfluoroalkyl radical having 5 to 8 carbon atoms, preferably having 7 carbon atoms~
~he perfluoroalkyl radicals R~, R'~ and R"~ are preferably straight-chain. The particularly preferred compounds of _ 3 ~ r~3~
the formulae (1) to ( 3 ) are thus n-C7Fl5CF=C~ICH2N ( C2~[40H ) 2 n-C7Fl5CON~C3H6N ( C2H4OH ) 2 n-C7Fl5CONHC3H6N ( C 2H40H ) 2 The fluoro~urfac~ants to ~e used according to ~he inven-tion have been described in the printed publications German Offenlegungsschrift 20749,331, US Patent 3,836~552 and US Patent 3l562,lS6, but there i~ no indication or suggestion at all to the effect that precisely these fluorosurfactants would be advantageous and effective means for stimulating hydrocarbon-bearing formation3.
These fluorosurfactant~ represent more or le~s vi~cous to pasty substances. The fluorosurfactants of the formula (1) can be prepared by reaction~ accordin~ to the follow-ing e~uations, in which a particular fluorine compound i~
used as an ex~mple:
C8Fl~CH2CH2I + Nat CH3 ~ > CaFl7CEI~CH2 +
NaI + CH30H
CsF17CH=CH2 + NH(~2~4H)2 ----> HF +
C7F15CF=CHCH2N ( C2H4H ) 2 The fluorosurfactants of the formula (2) can be prepared by a reaction according to the following equa ion, in which again a particular fluorine compound i8 used a~ an example:
C7F1sC~C2Hs + H2~(CH2)3N(~2H40H) 2 ~ >
o C7F1sC~NH(CH2)3N(~2H4~) 2 + C2H50H
~he fluorosurfactants of the formula (3) can be prepared by a reaction according to the following equation:
o ~ 3~
C7F15C-~H(CH2)3N(C2H4OH) 2 ~ H22 C7F1s~-NH(cH2)3N(c2H~oH) 2 + H20 O
In other re~pects, reference may ba made to the cited printed publications.
The effectiveness of the fluorosurfactant~ according to the invention is~ surprisingly, increased considerably if they are u~ed in a mixture with certain non-fluorinated nonionic ~urfactan~, namely with alkoxypolyethylene glycol ethers which contain 6 to 18 carbon atoms, prefer-ably 8 to lS carbon atoms, in the ~lko~y moiety and 3 to 15 ethylene o~ide units, preferably 6 to 12 ethylene oxide units, in the polyethylene glycol ether moiety; for example octyl polyglycol ether having 10 ethylene oxide units, decyl polyglycol ether having 6 ethylene oxide units and isotri~ecyl polyglycol ether having 8 ethylene oxide units, or with alkylphenoxypolyethylene glycol ethers which contain 6 to 18 carbon atoms, preferably 8 to 12 carbon atoms, in the alkyl moiety and 3 to 15 ethylene oxide units, preferably 6 to 12 ethylene oxide units, in the polyethylene glycol ether moiety, for example octylphenol or isooctylphenol polyglycol ether having 10 ethylene oxide units, nonylphenol polyglycol ether having 10 ethylene oxide units and dodecylphenol polyglycol ether having 8 ethylene o~ide unit~. The non-fluorina~ed nonionic ~urfactants men~ionQd are thus selected fatty alcohol ethoxylates and alkylphenol ethoxylates having the indicated nu~ber of carbon atoms in the hydrophobic radical and having the indicated number of ethylene oxide units. The fluoro~uractant~ to be u~ed according to ~he invention are preferably combined with one or more (as a rule one) fatty alcohol ethoxylate or with one or more ( d8 a rule one) alkyl-phenol ethoxylate, the combination with a fatty alcohol ethoxylate being preferred. These stimulant~ composed of - 5 ~ r~3~
fluorosurfactant ~nd fatty alcohol ethoxylate or alkyl-phenol ethoxylate contain the two mix~ure components preferably in a weight ratio of 1 . 1 With particular preference, th~ indicated fluorosurfactants are u3ed together with fatty alcohol ethoxylate and with al~yl-phenol ethoxylate. In these mixtures of three components, the weight ratio of the component6 i~ prefer-ably 1 : 1 : 1. The ~timulant~ according to the invan-tion in the form of the fluorosurfactants of the formul~e (1) to (3) or in the form of the mixtures de~rribed of these fluoro~urfactants and the indicated alkoxypolyethy-lene glycol ethers and/or alkylphenoxypolyethylene glycol ethers are particularly effective, in particular those having the three ~aid component~, which i~ probably the result of an unexpectedly large synergistic effect.
The stLmulant composed of the said three components i8 novel. The invention therefore also relates to an agent for stimulating oil and ga~ wells in oil and gas produc-tion from subterranean formation~. The ~timulant accoxd-ing to the invention i8 composed essentially of a) atleast one fluoro~urfactant of the formulae (1) to (3) described, b) at least one alkoxypolyethylene glycol ether having 6 to 18 carbon atoms, preferahly B to 15 carbon atoms, in the alkoxy moiety and 3 to 15 ethy-lene oxide units, preferably 6 to 12 ethylene oxideunits, in the polyethylene glycol ether moiety, and of c) at least one alkylphenoxypolyethylene glycol ether having 6 to 18 carbon atoms, preferably 8 to 12 carbon atoms, in the alkyl moiety and 3 to 15 ethylene o~ide unit~, preferably 6 to 12 ethylene oxide units, in the polyethylene glycol ether moiety, the three component~ a) to cj being pre~ent in a weight ratio of preferably ~ 1. A3 a rule, only one representative of each component is used. In other respect~, the above comments apply to the three components. The stimulant~ according to the invention are produced by mixing the component~
together, advantageously with stirring, at a temperature of preferably 20 to 50C.
The stLmulants according to the inYention, 1.e. both the fluorosurfactants of the formulae (1) to (3) and the said mixtures of the fluorosurfactan~s and the said ethoxy-lates, are as a rule soluble in w~ker. ~o improve the ease of handling (pourahility), they are in general blended with an appropriate quantity of water and/or with lower alcohols, such as methanol, e~hanol~ propanol, isopropanol and/or e~hylene glycol.
The contac~ing of the stimulant~ to be used according to ~0 the invention with the hydrocarbon-bearing ffubterranean reservoir can be carried out by the methods known per ~e.
Accordingly, the ~timulant i~ preferably u~ed in a carrier fluid (dissolv~d or dispersed) which, in the present case, advantageou~ly i8 essentially composed of waterO The concentration of ~timulant in the carrier fluid can vary within wide limits, and this is 0.001 to 10 % by weight, preferably 0.05 to 5 % by weight, the percentages by weight relati~g to the weight of the carrier fluid. The carrier fluid containing the stimu-lant is introduced into the reservoir to be treated undera high pressure, which may be at a higher or lower level, until the desired increase in hydrocarbon production has been reached again. Lower alcohol6 (methanol or iso-propanol), ~alts and/or acids or alkalis for adjusting the pH of the fluid to an advantageous value can be added to the aqueous carrier fluid; by means of these methods likewise known per se, a better distribution of the stLmulant in the reservoir can be achieved if neces~ary (the carrier fluid i6 thus under~tood to mean the fluid medium and all further additiv2s, with the e~ception of the stimulant).
.
The stimulants according to the invention have a number of advantages. AB already mentioned, they are particu-larly effective and therefore lead to a pronounced increase in the production rate of gas and oil. ~hey are also active even in a low concentration. Because of their special surfactant properties, a high recovery rate - 7 ~ J7~
of the ~tLmulant fluid i8 al80 obtained; in view of the high price of fluoro~urfac~ant~, thi~ i~ a further particular advantage.
~ he invention will now be explained in greater dstail by reference to ~xamples:
As a measure of the effectiveness of the stimulants described, their adsorption behavior on Oklahoma No. 1 ~and i~ testedO This test method (which i~ analogous to that de~cribed by Henry B. Clark et al. in Journal of Petroleum Technolo~y, July 1982, pages 1,565 to 1,569) is indicated in detail below:
The ~dsorption te~ts are carried out in a burette (length: 350 mm, internal diameter: 19 mm) which has been filled with 50 g of Oklahoma No. 1 sand between two pad~
of glass wool. The test solutions are prepared as follows: initially, a solution of 50 % by wsight of isopropanol, 49 % by weight of distilled water and 1 % by weight of stLmulant is prepared. 1 ml of this 1 % by weight solution is dissolved in 250 ml of a 2 % by weight aqueous ~Cl solution (i.e. about 40 mg of stLmulant per liter). 11 ml of the test solution thu~ obtained are filled into the burette and then ~ub~ected for 1 to 2 hour~ to a pressure of 35,150 Pa. The solution iB then forced out by opening the cock of the burette and apply-ing a pressure of 105,450 Pa, and its surface tension i8 measured by the Du Nouy method (DI~ 53 914). This procedure is repeated five tLmes in the same burette, with the ~ame ~and filling, using 11 ml of test solution each time. The surface tension value of the thlrd test solution forced out of the burette (i.e. the third eluate) should be less than 35 m~/m, preferably le~s than 30 mNtm.
The following stLmulants to be u~ed according to ~he invention were tested:
'7~
Example 1 The stimulant is a mixture of n-C7Fl5CF=CHCH2N ~ C2H40H ) 2 1 i~otridecyl polyglycol ether with 8 ethylene oxide units and nonylphenol polyglycol e~her wikh 10 ethylena oxide units in a weight ratio of 1 : 1 o 1.
E~a~pl~ 2 The stimulant is a mixture of n-C7Fl5CONHC3H6N ( C2H40H ) 2, isotridecyl polyglycol ether with 1~ 8 ethylene oxide units and nonylphenol polyglycol ether with 10 ethylene oxide units in a weight ratio of 1 Example 3 The stimulant is a mixture of n-C7Fl5CONHC3H6N t C2H40H ) isotridecyl polyglycol ether with 8 ethylene oxide unit~
and nonylphenol polyglycol ether with 10 ethylene oxide units in a weight ratio of 1 Comparison example Example 1 was repeated, the fluorine compound used being the fluorosurfactant Fluorad~ Well Stimulation ~dditive FC-750 from Minne60ta Mining and ~anufacturing (3M~
Company, USA (~ = regi~tered trademark of 3M), which i5 commercially available and described a~ particularly effective; this fluorosur~actant is a fluorinated quater-nary alkylammonium iodide.
The mixtures (stimulants) from Exzmple~ 1 to 3 according to the invention and the compari~on example were prepared by mixing the three components at room temperature.
in ~he molecule are de~cribed as a stimulating agent which is introduced into the subterranean formation to be treated.
The rçduction in the abovementioned interfacial tension values, achieved by mean~ of the known fluoro~urfactanks, still leaves something to be desired. The effectivene~s of the fluorosurfactants is also xeduced to a greater or lesser extent by adsorption losse~ during con~acting with the formation which i~ to be treated. There is thus ~0 still a demand for suitable and highly effective fluoro-surfactants for the purpose in guestion.
To meet this demand, it has been found that fluoro-surfactants with a very narrow range with xespect to the carbon atoms in the perfluoroalkyl radical and with the specific qroup -N(CH2CH2OH)2 in the mole~ule are advan-tageous and unexpectedly effective stimulants for the treatment of the formation~ in question.
The proces~ according to the invention for stLmulating oil and ga~ wells in oil and gas production from sub-terranean formation~, the oil/gas-containing formation being contacted in the region of the well with a stimu-lant from the group comprising the fluorosurfactants, comprises using as the stimulant at least ona fluoro-surfactant of the following formulae (1) to ~3), F~-CF=CHCH2N(C2H4H) 2 ( 1 ) R'f-CONHC3~6N(C2H4H)2 (2) R~y~CONHC3H6~(c2H4O~)2 (3~
o in which Rf, R~r and R"~ are a perfluoroalkyl radical having 5 to 8 carbon atoms, preferably having 7 carbon atoms~
~he perfluoroalkyl radicals R~, R'~ and R"~ are preferably straight-chain. The particularly preferred compounds of _ 3 ~ r~3~
the formulae (1) to ( 3 ) are thus n-C7Fl5CF=C~ICH2N ( C2~[40H ) 2 n-C7Fl5CON~C3H6N ( C2H4OH ) 2 n-C7Fl5CONHC3H6N ( C 2H40H ) 2 The fluoro~urfac~ants to ~e used according to ~he inven-tion have been described in the printed publications German Offenlegungsschrift 20749,331, US Patent 3,836~552 and US Patent 3l562,lS6, but there i~ no indication or suggestion at all to the effect that precisely these fluorosurfactants would be advantageous and effective means for stimulating hydrocarbon-bearing formation3.
These fluorosurfactant~ represent more or le~s vi~cous to pasty substances. The fluorosurfactants of the formula (1) can be prepared by reaction~ accordin~ to the follow-ing e~uations, in which a particular fluorine compound i~
used as an ex~mple:
C8Fl~CH2CH2I + Nat CH3 ~ > CaFl7CEI~CH2 +
NaI + CH30H
CsF17CH=CH2 + NH(~2~4H)2 ----> HF +
C7F15CF=CHCH2N ( C2H4H ) 2 The fluorosurfactants of the formula (2) can be prepared by a reaction according to the following equa ion, in which again a particular fluorine compound i8 used a~ an example:
C7F1sC~C2Hs + H2~(CH2)3N(~2H40H) 2 ~ >
o C7F1sC~NH(CH2)3N(~2H4~) 2 + C2H50H
~he fluorosurfactants of the formula (3) can be prepared by a reaction according to the following equation:
o ~ 3~
C7F15C-~H(CH2)3N(C2H4OH) 2 ~ H22 C7F1s~-NH(cH2)3N(c2H~oH) 2 + H20 O
In other re~pects, reference may ba made to the cited printed publications.
The effectiveness of the fluorosurfactant~ according to the invention is~ surprisingly, increased considerably if they are u~ed in a mixture with certain non-fluorinated nonionic ~urfactan~, namely with alkoxypolyethylene glycol ethers which contain 6 to 18 carbon atoms, prefer-ably 8 to lS carbon atoms, in the ~lko~y moiety and 3 to 15 ethylene o~ide units, preferably 6 to 12 ethylene oxide units, in the polyethylene glycol ether moiety; for example octyl polyglycol ether having 10 ethylene oxide units, decyl polyglycol ether having 6 ethylene oxide units and isotri~ecyl polyglycol ether having 8 ethylene oxide units, or with alkylphenoxypolyethylene glycol ethers which contain 6 to 18 carbon atoms, preferably 8 to 12 carbon atoms, in the alkyl moiety and 3 to 15 ethylene oxide units, preferably 6 to 12 ethylene oxide units, in the polyethylene glycol ether moiety, for example octylphenol or isooctylphenol polyglycol ether having 10 ethylene oxide units, nonylphenol polyglycol ether having 10 ethylene oxide units and dodecylphenol polyglycol ether having 8 ethylene o~ide unit~. The non-fluorina~ed nonionic ~urfactants men~ionQd are thus selected fatty alcohol ethoxylates and alkylphenol ethoxylates having the indicated nu~ber of carbon atoms in the hydrophobic radical and having the indicated number of ethylene oxide units. The fluoro~uractant~ to be u~ed according to ~he invention are preferably combined with one or more (as a rule one) fatty alcohol ethoxylate or with one or more ( d8 a rule one) alkyl-phenol ethoxylate, the combination with a fatty alcohol ethoxylate being preferred. These stimulant~ composed of - 5 ~ r~3~
fluorosurfactant ~nd fatty alcohol ethoxylate or alkyl-phenol ethoxylate contain the two mix~ure components preferably in a weight ratio of 1 . 1 With particular preference, th~ indicated fluorosurfactants are u3ed together with fatty alcohol ethoxylate and with al~yl-phenol ethoxylate. In these mixtures of three components, the weight ratio of the component6 i~ prefer-ably 1 : 1 : 1. The ~timulant~ according to the invan-tion in the form of the fluorosurfactants of the formul~e (1) to (3) or in the form of the mixtures de~rribed of these fluoro~urfactants and the indicated alkoxypolyethy-lene glycol ethers and/or alkylphenoxypolyethylene glycol ethers are particularly effective, in particular those having the three ~aid component~, which i~ probably the result of an unexpectedly large synergistic effect.
The stLmulant composed of the said three components i8 novel. The invention therefore also relates to an agent for stimulating oil and ga~ wells in oil and gas produc-tion from subterranean formation~. The ~timulant accoxd-ing to the invention i8 composed essentially of a) atleast one fluoro~urfactant of the formulae (1) to (3) described, b) at least one alkoxypolyethylene glycol ether having 6 to 18 carbon atoms, preferahly B to 15 carbon atoms, in the alkoxy moiety and 3 to 15 ethy-lene oxide units, preferably 6 to 12 ethylene oxideunits, in the polyethylene glycol ether moiety, and of c) at least one alkylphenoxypolyethylene glycol ether having 6 to 18 carbon atoms, preferably 8 to 12 carbon atoms, in the alkyl moiety and 3 to 15 ethylene o~ide unit~, preferably 6 to 12 ethylene oxide units, in the polyethylene glycol ether moiety, the three component~ a) to cj being pre~ent in a weight ratio of preferably ~ 1. A3 a rule, only one representative of each component is used. In other respect~, the above comments apply to the three components. The stimulant~ according to the invention are produced by mixing the component~
together, advantageously with stirring, at a temperature of preferably 20 to 50C.
The stLmulants according to the inYention, 1.e. both the fluorosurfactants of the formulae (1) to (3) and the said mixtures of the fluorosurfactan~s and the said ethoxy-lates, are as a rule soluble in w~ker. ~o improve the ease of handling (pourahility), they are in general blended with an appropriate quantity of water and/or with lower alcohols, such as methanol, e~hanol~ propanol, isopropanol and/or e~hylene glycol.
The contac~ing of the stimulant~ to be used according to ~0 the invention with the hydrocarbon-bearing ffubterranean reservoir can be carried out by the methods known per ~e.
Accordingly, the ~timulant i~ preferably u~ed in a carrier fluid (dissolv~d or dispersed) which, in the present case, advantageou~ly i8 essentially composed of waterO The concentration of ~timulant in the carrier fluid can vary within wide limits, and this is 0.001 to 10 % by weight, preferably 0.05 to 5 % by weight, the percentages by weight relati~g to the weight of the carrier fluid. The carrier fluid containing the stimu-lant is introduced into the reservoir to be treated undera high pressure, which may be at a higher or lower level, until the desired increase in hydrocarbon production has been reached again. Lower alcohol6 (methanol or iso-propanol), ~alts and/or acids or alkalis for adjusting the pH of the fluid to an advantageous value can be added to the aqueous carrier fluid; by means of these methods likewise known per se, a better distribution of the stLmulant in the reservoir can be achieved if neces~ary (the carrier fluid i6 thus under~tood to mean the fluid medium and all further additiv2s, with the e~ception of the stimulant).
.
The stimulants according to the invention have a number of advantages. AB already mentioned, they are particu-larly effective and therefore lead to a pronounced increase in the production rate of gas and oil. ~hey are also active even in a low concentration. Because of their special surfactant properties, a high recovery rate - 7 ~ J7~
of the ~tLmulant fluid i8 al80 obtained; in view of the high price of fluoro~urfac~ant~, thi~ i~ a further particular advantage.
~ he invention will now be explained in greater dstail by reference to ~xamples:
As a measure of the effectiveness of the stimulants described, their adsorption behavior on Oklahoma No. 1 ~and i~ testedO This test method (which i~ analogous to that de~cribed by Henry B. Clark et al. in Journal of Petroleum Technolo~y, July 1982, pages 1,565 to 1,569) is indicated in detail below:
The ~dsorption te~ts are carried out in a burette (length: 350 mm, internal diameter: 19 mm) which has been filled with 50 g of Oklahoma No. 1 sand between two pad~
of glass wool. The test solutions are prepared as follows: initially, a solution of 50 % by wsight of isopropanol, 49 % by weight of distilled water and 1 % by weight of stLmulant is prepared. 1 ml of this 1 % by weight solution is dissolved in 250 ml of a 2 % by weight aqueous ~Cl solution (i.e. about 40 mg of stLmulant per liter). 11 ml of the test solution thu~ obtained are filled into the burette and then ~ub~ected for 1 to 2 hour~ to a pressure of 35,150 Pa. The solution iB then forced out by opening the cock of the burette and apply-ing a pressure of 105,450 Pa, and its surface tension i8 measured by the Du Nouy method (DI~ 53 914). This procedure is repeated five tLmes in the same burette, with the ~ame ~and filling, using 11 ml of test solution each time. The surface tension value of the thlrd test solution forced out of the burette (i.e. the third eluate) should be less than 35 m~/m, preferably le~s than 30 mNtm.
The following stLmulants to be u~ed according to ~he invention were tested:
'7~
Example 1 The stimulant is a mixture of n-C7Fl5CF=CHCH2N ~ C2H40H ) 2 1 i~otridecyl polyglycol ether with 8 ethylene oxide units and nonylphenol polyglycol e~her wikh 10 ethylena oxide units in a weight ratio of 1 : 1 o 1.
E~a~pl~ 2 The stimulant is a mixture of n-C7Fl5CONHC3H6N ( C2H40H ) 2, isotridecyl polyglycol ether with 1~ 8 ethylene oxide units and nonylphenol polyglycol ether with 10 ethylene oxide units in a weight ratio of 1 Example 3 The stimulant is a mixture of n-C7Fl5CONHC3H6N t C2H40H ) isotridecyl polyglycol ether with 8 ethylene oxide unit~
and nonylphenol polyglycol ether with 10 ethylene oxide units in a weight ratio of 1 Comparison example Example 1 was repeated, the fluorine compound used being the fluorosurfactant Fluorad~ Well Stimulation ~dditive FC-750 from Minne60ta Mining and ~anufacturing (3M~
Company, USA (~ = regi~tered trademark of 3M), which i5 commercially available and described a~ particularly effective; this fluorosur~actant is a fluorinated quater-nary alkylammonium iodide.
The mixtures (stimulants) from Exzmple~ 1 to 3 according to the invention and the compari~on example were prepared by mixing the three components at room temperature.
3~:3~3~
g _ In the table which follow~ e ~urface ~ension valua~ of the first to fifth eluates of th2 ad~orption test de-scribed are indicated:
. . .~
Stimulant Surface tension (mN/m~ of the test solutions and of the 1st to 5th eluates _ Test solution l~t. 2nd. 3rd. 4th. 5th.
Example 1 l9 41 30 29 28 26 Example 2 22 39 35 29 29 29 Example 3 23 37 32 28 28 27 Comparison example 22 51 51 48 41 40 . _ _ _ As the examples show, the stimulant~ according to the invention pa~s the demanded test and are therefore very effective in oil and gas production from hydrocarbon--bearing subterranean formations. Above all, they hare a particularly advantageous ad~orption behavior, i.e. the loss of fluorosurfactant due to adsorption proce~ses is small. The same result was al~o obtained ~hen isooctyl-phenol polyglycol ether with lO ethylene oxide units was used in place of nonylphenol poly~lycol ether with 10 ethylene oxide units.
g _ In the table which follow~ e ~urface ~ension valua~ of the first to fifth eluates of th2 ad~orption test de-scribed are indicated:
. . .~
Stimulant Surface tension (mN/m~ of the test solutions and of the 1st to 5th eluates _ Test solution l~t. 2nd. 3rd. 4th. 5th.
Example 1 l9 41 30 29 28 26 Example 2 22 39 35 29 29 29 Example 3 23 37 32 28 28 27 Comparison example 22 51 51 48 41 40 . _ _ _ As the examples show, the stimulant~ according to the invention pa~s the demanded test and are therefore very effective in oil and gas production from hydrocarbon--bearing subterranean formations. Above all, they hare a particularly advantageous ad~orption behavior, i.e. the loss of fluorosurfactant due to adsorption proce~ses is small. The same result was al~o obtained ~hen isooctyl-phenol polyglycol ether with lO ethylene oxide units was used in place of nonylphenol poly~lycol ether with 10 ethylene oxide units.
Claims (10)
1. A process for stimulating oil and gas wells in oil and gas production from subterranean formations, the oil/gas-containing formation being contacted in the region of the well with a stimulant from the group comprising the fluorosurfactants, which comprises using as the stimulant at least one fluorosurfactant of the following formulae (1) to (3), Rf-CF=CHCH2N(C2H4OH)2 (1) R'f-CONHC3H8N(C2H4OH)2 (2) R"f-CONHC3H8?(C2H4OH)2 (3) in which Rf, R'f and R"f are a perfluoroalkyl radical having 5 to 8 carbon atoms.
2. The process as claimed in claim 1, wherein Rf, R'f and R"f are a perfluoroalkyl radical having 7 carbon atoms.
3. The process as claimed in claim 1 or 2, wherein the stimulant used is a fluorosurfactant in combination with at least one non-fluorinated nonionic sur-factant selected from the group comprising alkoxy-polyethylene glycol ethers having 6 to 18 carbon atoms in the alkoxy moiety and 3 to 15 ethylene oxide units in the polyethylene glycol ether moiety and alkylphenoxypolyethylene glycol ethers having 6 to 18 carbon atoms in the alkyl moiety and 3 to 15 ethylene oxide units in the polyethylene glycol ether moiety.
4. The process as claimed in claim 1 or 2, wherein the stimulant used is a fluorosurfactant in combination with an alkoxypolyethylene glycol ether having 6 to 18 carbon atoms in the alkoxy moiety and 3 to 15 ethylene oxide units in the polyethylene glycol ether moiety or an alkylphenoxypolyethylene glycol ether having 6 to 18 carbon atoms in the alkyl moiety and 3 to 15 ethylene oxide units in the polyethylene glycol ether moiety, in a weight ratio of 1 : 1.
5. The process as claimed in claim 1 or 2, wherein the stimulant used is a fluorosurfactant in combination with an alkoxypolyethylene glycol ether having 6 to 18 carbon atoms in the alkoxy moiety and 3 to 15 ethylene oxide units in the polyethylene glycol ether moiety and an alkylphenoxypolyethylene glycol ether having 6 to 18 carbon atoms in the alkyl moiety and 3 to 15 ethylene oxide units in the polyethylene glycol ether moiety, in a weight ratio of 1 : 1 : 1.
6. The process as claimed in one or more of claims 1 to 5, wherein the stimulant is employed in an aqueous carrier fluid.
7. The process as claimed in one or more of claims 1 to 5, wherein the stimulant is employed in an aqueous carrier fluid, the quantity of stimulant being 0.001 to 10 % by weight, the percentages by weight relat-ing to the weight of the carrier fluid.
8. The process as claimed in one or more of claims 1 to 7, wherein the contacting of the subterranean formation with the stimulant is effected by inject-ing the latter into the formation.
9. A stimulant for stimulating oil and gas wells in oil and gas production from subterranean formations, composed essentially of a) at least one fluorosurfactant of the following formulae (1) to (3) Rf-CF=CHCH2N(C2H4OH)2 (1) R'f-CONHC3H6N(C2H4OH)2 (2) R"f-CONHC3H6?(C2H4OH)2 (3) in which Rf, R'f and R"f are a perfluoroalkyl radical having 5 to 8 carbon atoms, b) at least one alkoxypolyethylene glycol ether having 6 to 18 carbon atoms in the alkoxy moiety and 3 to 15 ethylene oxide units in the poly-ethylene glycol ether moiety and c) at least one alkylphenoxypolyethylene glycol ether having 6 to 18 carbon atoms in the alkyl moiety and 3 to 15 ethylene oxide units in the polyethylene glycol ether moiety, in an a) : b) : c) weight ratio of 1 : 1 : 1.
10. A stimulant as claimed in claim 9, composed essen-tially of a) at least one fluorosurfactant of the following formuale n-C7F15CF=CHCH2N(C2H4OH)2 n-C7F15CONHC3H6N(C2H4OH)2 n-C7F15CONHC3H6?(C2H4OH)2 b) isotridecyl polyglycol ether having 8 ethylene oxide units and c) nonylphenol polyglycol ether having 10 ethylene oxide units or isooctyl phenol polyglycol ether having 10 ethylene oxide units, in an a) : b) : c) weight ratio of 1 : 1 : 1.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3904092.5 | 1989-02-11 | ||
| DE3904092A DE3904092A1 (en) | 1989-02-11 | 1989-02-11 | METHOD FOR THE STIMULATION OF OIL AND GAS PROBE IN THE EXTRACTION OF OIL AND GAS FROM UNDERGROUND FORMATIONS AND STIMULATING AGENTS THEREFOR |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2009732A1 true CA2009732A1 (en) | 1990-08-11 |
Family
ID=6373865
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002009732A Abandoned CA2009732A1 (en) | 1989-02-11 | 1990-02-09 | Process for stimulating oil and gas wells in oil and gas production from subterranean formations, and stimulant for this purpose |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0383163B1 (en) |
| CA (1) | CA2009732A1 (en) |
| DE (2) | DE3904092A1 (en) |
| NO (1) | NO900642L (en) |
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| US7585817B2 (en) | 2006-08-23 | 2009-09-08 | Board Of Regents, The University Of Texas System | Compositions and methods for improving the productivity of hydrocarbon producing wells using a non-ionic fluorinated polymeric surfactant |
| US7629298B2 (en) | 2006-02-21 | 2009-12-08 | 3M Innovative Properties Company | Sandstone having a modified wettability and a method for modifying the surface energy of sandstone |
| US7772162B2 (en) | 2006-03-27 | 2010-08-10 | Board Of Regents, The University Of Texas System | Use of fluorocarbon surfactants to improve the productivity of gas and gas condensate wells |
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| US8043998B2 (en) | 2007-03-23 | 2011-10-25 | Board Of Regents, The University Of Texas System | Method for treating a fractured formation with a non-ionic fluorinated polymeric surfactant |
| US8138127B2 (en) | 2007-03-23 | 2012-03-20 | Board Of Regents, The University Of Texas | Compositions and methods for treating a water blocked well using a nonionic fluorinated surfactant |
| US8261825B2 (en) | 2007-11-30 | 2012-09-11 | Board Of Regents, The University Of Texas System | Methods for improving the productivity of oil producing wells |
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| US8629089B2 (en) | 2008-12-18 | 2014-01-14 | 3M Innovative Properties Company | Method of contacting hydrocarbon-bearing formations with fluorinated ether compositions |
| US8678090B2 (en) | 2007-12-21 | 2014-03-25 | 3M Innovative Properties Company | Methods for treating hydrocarbon-bearing formations with fluorinated polymer compositions |
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| US9353309B2 (en) | 2007-03-23 | 2016-05-31 | Board Of Regents, The University Of Texas System | Method for treating a formation with a solvent |
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Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3562156A (en) * | 1969-06-12 | 1971-02-09 | Minnesota Mining & Mfg | Fire extinguishing composition comprising a fluoroaliphatic surfactant and a fluorine-free surfactant |
| NL172234C (en) * | 1971-06-02 | 1983-08-01 | Hoechst Ag | METHOD FOR PREPARING PERFLUORATED CARBONIC ACID AMIDEAMINE COMPOUNDS. |
| US3811504A (en) * | 1973-02-09 | 1974-05-21 | Texaco Inc | Surfactant oil recovery process usable in formations containing water having high concentrations of polyvalent ions such as calcium and magnesium |
| DE2749331C2 (en) * | 1977-11-04 | 1982-07-01 | Hoechst Ag, 6000 Frankfurt | Foam concentrate |
| US4460791A (en) * | 1978-09-22 | 1984-07-17 | Ciba-Geigy Corporation | Oil recovery by fluorochemical surfactant waterflooding |
| DE3614040A1 (en) * | 1986-04-25 | 1987-11-05 | Henkel Kgaa | TURBINE-FREE STABILIZATION OF WATER IN HYDROCARBON FRACTIONS OF THE DIESEL OR. HEATING OIL AREA |
| FR2609751B1 (en) * | 1987-01-20 | 1996-02-02 | Inst Francais Du Petrole | USE OF SURFACTANT BASED SURFACTANT FOAMS FOR IMPROVING THE GAS SCAN OF AN OIL FORMATION |
| DE3725938A1 (en) * | 1987-08-05 | 1989-02-16 | Hoechst Ag | AQUEOUS TENSIDE SETTINGS AND THEIR USE IN PETROLEUM PRODUCTION |
-
1989
- 1989-02-11 DE DE3904092A patent/DE3904092A1/en not_active Withdrawn
-
1990
- 1990-02-07 DE DE9090102343T patent/DE59000096D1/en not_active Expired - Fee Related
- 1990-02-07 EP EP90102343A patent/EP0383163B1/en not_active Expired - Lifetime
- 1990-02-09 CA CA002009732A patent/CA2009732A1/en not_active Abandoned
- 1990-02-09 NO NO90900642A patent/NO900642L/en unknown
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Also Published As
| Publication number | Publication date |
|---|---|
| NO900642L (en) | 1990-08-13 |
| DE3904092A1 (en) | 1990-08-16 |
| DE59000096D1 (en) | 1992-05-27 |
| NO900642D0 (en) | 1990-02-09 |
| EP0383163B1 (en) | 1992-04-22 |
| EP0383163A1 (en) | 1990-08-22 |
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