| 主权项 |
1. A process for mineral oil production, in which an aqueous formulation comprising at least one water-soluble, hydrophobically associating copolymer (A) and at least one surfactant (B) is injected through at least one injection borehole into a mineral oil deposit, and crude oil is withdrawn from the deposit through at least one production borehole, wherein
(A) the water-soluble, hydrophobically associating copolymer comprises
(Aa) 0.1 to 15% by weight of at least one monoethylenically unsaturated, hydrophobically associating monomer (Aa), selected from the group of
H2C═C(R1)—R2—O—(—CH2—CH(R3)—O—)k+CH2—CH(R4)—O—)l—R5 (I),H2C═C(R1)—O—(—CH2—CH(R3)—O—)k—R6 (II),H2C═C(R1)—(C═O)—O—(—CH2—CH(R3)—O—)k—R6 (III),where the -(—CH2—CH(R3)—O—)k and -(—CH2—CH(R4)—O—)l units are arranged in block structure in the sequence shown in formula (I) and the radicals and indices are each defined as follows:k: a number from 10 to 150,l: a number from 5 to 25,R1: H or methyl,R2: a single bond or a divalent linking group selected from the group of —(CnH2n)— [R2a], —O—(Cn′H2n′)— [R2b] and —C(O)—O—(Cn″H2n″)— [R2c], where n, n′ and n″ are each natural numbers from 1 to 6,R3: each independently H, methyl or ethyl, with the proviso that at least 50 mol % of the R2 radicals are H,R4: each independently a hydrocarbyl radical having at least 2 carbon atoms or an ether group of the general formula —CH2—O—R4′, where R4′ is a hydrocarbyl radical having at least 2 carbon atoms,R5: H or a hydrocarbyl radical having 1 to 30 carbon atoms,R6: an aliphatic and/or aromatic, straight-chain or branched hydrocarbyl radical having 8 to 40 carbon atoms,and also(Ab) 85 to 99.9% by weight of at least one monoethylenically unsaturated, hydrophilic monomers (Ab) different than (Aa), where the monomers (Ab) comprise
(Ab1) at least one uncharged, monoethylenically unsaturated, hydrophilic monomer (b1), selected from the group of (meth)acrylamide, N-methyl(meth)acrylamide, N,N′-dimethyl(meth)acrylamide or N-methylol(meth)acrylamide, and(Ab2) at least one anionic, monoethylenically unsaturated, hydrophilic monomer (Ab2) which at least one acidic group selected from the group of —COOH, —SO3H and —PO3H2 and salts thereof,where the proportions are each based on the total amount of all monomers in the copolymer and the copolymer has a weight-average molecular weight MW of 1*106 g/mol to 30*106 g/mol, and wherein (B) the at least one surfactant is a nonionic and/or anionic surfactant which is selected from the group of
(Ba) nonionic surfactants of the general formula
R15—O—(R16O)a—H (VII) where the radicals are each defined as follows:R15: a C10- to C36-hydrocarbyl radical,R16O: independently an alkyleneoxy group having 2 to 4 carbon atoms, with the proviso that at least 50 mol % of the R16O radicals are 1,2-ethyleneoxy groups,a: a number from 3 to 100,(Bb) anionic surfactants of the general formula R15—O—(R17O)b—R18—Y (VIII)
where the radicals are each defined as follows:R15: as already defined,R17O: independently alkyleneoxy groups having 2 to 4 carbon atoms, with the proviso that at least 30 mol % of the R17 radicals are 1,2-ethyleneoxy groups and/or 1,2-propyleneoxy groups,R18: a single bond or a divalent hydrocarbyl group having 1 to 10 carbon atoms,b: a number from 1 to 100, andY: an acidic group or a salt thereof, selected from the group of sulfonate groups, sulfate groups, phosphonate groups, phosphoric acid groups or carboxyl groups,(Bc) star-shaped nonionic surfactants of the general formula R19[(O—(CH—CH(R20)—O)c—(CH2CH2O)d—(CH—CH(R20)—O)e—H]f(IX) where the radicals are each defined as follows:
f: a number from 3 to 9,R19: an f-valent hydrocarbyl radical,R20: an aliphatic hydrocarbyl radical having 1 to 3 carbon atoms,c: a number from 0 to 2,d: a number from 2 to 50,e: a number from 2 to 50, and where
the amount of the copolymers (A) in the formulation is 0.02 to 2% by weight,the amount of the surfactants (B) is 0.005 to 1.0% by weight, andthe viscosity of the formulation is at least 5 mPas (measured at 25° C.).
|
