CN1560177A

CN1560177A - High temp. thicking oil viscosity reducing agent and preparation process thereof

Info

Publication number: CN1560177A
Application number: CNA2004100236133A
Authority: CN
Inventors: 葛际江; 张贵才; 孙铭勤; 宋昭峥
Original assignee: China University of Petroleum East China
Current assignee: China University of Petroleum East China
Priority date: 2004-02-25
Filing date: 2004-02-25
Publication date: 2005-01-05

Abstract

The invention provides a higher-temperature resistant crude oil viscosity reductant and its preparing method, and it is N-alkyl-gama-di-quaternary cation surfactant, and its preparing method includes three steps: (1) taking aliphatic amine and catalyst in a three-mouthed bottle, dropping in acrylic nitricle at 30-60 deg.C and reacting for 4-8 hours, makeing N-alkyl-beta- amino-propionitrile; (2) adding the N-alkyl-beta-amino-propionitrile and solvent in a high-pressure kettle, displacing the air in the kettle with nitrogen gas, charging in hydrogen gas and chlorine gas and reacting for 1-2 hours at 80-90 deg.C, preparing N-alkyl trimethylene diamine; (3) adding N-alkyl trimethylene diamine and catalyst in the kettle, using nitrogen gas to displace the air in the kettle, raising temperature to 60 deg.C and charging in chloromethane, reacting at 80-90 deg.C at 0.49-0.59 MPa for 2-6 hours to prepare the surfactant, which is prepared into 25-30% water solution, obtaining the viscosity reductant. It need not mix with the alkali and has better viscosity-reducing effect on different crude oils at lower concentration.

Description

High-temperature thick oil viscosity reducer and preparation method thereof

The technical field is as follows:

the invention relates to a high-temperature thick oil viscosity reducer for an oil field.

Background art:

china has abundant thick oil resources, the geological reserve reaches 1640Mt, and the land thick oil accounts for more than 20% of the total petroleum resources.

The thickened oil has the outstanding characteristics of high content of colloid asphaltene and high viscosity, so the key points of the development of the thickened oil are to reduce the viscosity and improve the fluidity. At present, the main methods for exploiting extra-heavy oil in China are steam huff and puff, steam flooding and other thermal exploitation technologies. In the latter period of huffing and puff, the contradiction of low oil-gas ratio, high crude oil viscosity, difficult shaft lifting and the like in steam injection exploitation is increasingly prominent, and the further development of the heavy oil reservoir is restricted. The high-efficiency thick oil viscosity reducer is injected along with steam, so that the steam injection pressure can be reduced, the shaft lifting resistance is reduced, the economic benefit of steam injection production is improved, and the method is an effective way for improving the recovery efficiency in the later stage of multi-round huff and puff. Because the temperature of the steam is high (up to 350 ℃), the viscosity reducer injected with the steam is required to have high temperature resistance.

The heavy oil viscosity reducer is typically a surfactant. The surfactant used as viscosity reducer for thick oil mainly comprises nonionic surfactant, anionic surfactant and amphoteric surfactant, wherein the anionic surfactant and the nonionic-anionic amphoteric surfactant have high temperature resistance.

US4811788 and CN1115778 respectively report that non-ionic-anionic amphoteric surfactants such as polyoxyethylene eicosanol ether sulfonate and polyoxyethylene phenol-formaldehyde resin phosphate are used as viscosity reducers for thick oil, which can resist high temperature of 300-320 ℃, but the synthesis process is complex, the cost is high, and the practical value is not great.

CN1221650, CN1204680, CN1310221 and the like report that sulfonate surfactant is used as viscosity reducer for thick oil, HEA thick oil viscosity reducer developed by petroleum exploration and development institute, GY thick oil viscosity reducer developed by petroleum university and thick oil viscosity reducer developed by Xinjiang petroleum exploration and development institute are mainly composed of petroleum soap or naphthenate. The surfactants have low cost, high temperature resistance and low activity, and generally have good emulsification and viscosity reduction effects on thick oil only by being used together with alkaline substances. The addition of alkaline substances can cause clay swelling, scaling and the like, and has potential harm to the oil extraction process.

The invention content is as follows:

the invention aims to provide a thick oil viscosity reducer with high temperature resistance and a preparation method thereof. The viscosity reducer does not need to be compounded with alkali for use, and has a good viscosity reducing effect on different thickened oils at a lower concentration.

The purpose of the invention is realized by that the thick oil viscosity reducer is an N-alkyl-gamma-diquaternary ammonium cationic surfactant with the general structural formula of [ RN⁺(CH₃)₂CH₂CH₂CH₂N⁺(CH₃)₃]2Cl^-The molecular weight is 384-468.

The preparation method of the thickened oil viscosity reducer mainly comprises the following three steps of (1) putting a certain amount of fatty amine and a proper amount of catalyst into a three-necked bottle, dropwise adding acrylonitrile at 30-60 ℃, and reacting for 4-8 hours to obtain N-alkyl- β -aminopropionitrile, (2) adding a certain amount of N-alkyl- β -aminopropionitrile and a solvent into an autoclave, replacing air in the autoclave with nitrogen, introducing hydrogen and chlorine, reacting for 1-2 hours at 80-90 ℃ to obtain N-alkyl propylenediamine, (3) adding N-alkyl propylenediamine and a catalyst into the autoclave, replacing air in the autoclave with nitrogen, heating to 60 ℃, introducing methyl chloride, reacting for 2-6 hours at 80-90 ℃ and 0.49-0.59 MPa to obtain the N-alkyl-gamma-bis-quaternary ammonium cation surfactant, wherein the reaction equation is as follows:

the aliphatic amine may be dodecylamine, hexadecylamine or octadecylamine, and hexadecylamine is preferred.

The catalyst can be sodium hydroxide, sodium carbonate, triethanolamine and the like, and sodium carbonate is preferred.

The specific implementation mode is as follows:

the preparation process of the viscosity reducer for thick oil is illustrated by the following examples.

Example 1:

the first step is the preparation of N-hexadecyl- β -aminopropionitrile.

0.1mol of hexadecyl amine and 0.4g of sodium carbonate are added into a three-neck flask, the temperature is raised to 50 ℃, 0.125mol of acrylonitrile is dripped, and the reaction is carried out for 4 hours to obtain the N-hexadecyl- β -aminopropionitrile, wherein the conversion rate is 95%.

The second step is that: and preparing N-hexadecyl propane diamine.

0.1mol of N-alkyl- β -aminopropionitrile and 50ml of isopropanol are added into a high-pressure reaction kettle, the air in the kettle is replaced by nitrogen, hydrogen and chlorine are introduced, and the reaction is carried out for 2 hours at 80 ℃ to prepare the N-hexadecyl propanediamine, wherein the conversion rate is 97%.

The third step: and (3) preparing the N-hexadecane-gamma-diquaternary ammonium cationic surfactant.

Adding 0.1mol of N-hexadecyl propane diamine and 0.3mol of sodium carbonate into a high-pressure reaction kettle, replacing air in the kettle with nitrogen, heating to 60 ℃, introducing 0.8mol of methyl chloride, and reacting at 90 ℃ and 0.49-0.59 MPa for 4 hours to obtain the N-alkyl-gamma-bis-quaternary ammonium cationic surfactant with the conversion rate of 95%. The surfactant is prepared into a 25-30% aqueous solution, and the aqueous solution can be used as a thick oil viscosity reducer.

The invention has the characteristics that:

(1) the method is characterized in that an N-alkyl-gamma-diquaternary ammonium cationic surfactant is used as a thick oil viscosity reducer for the first time, and when the use concentration of the viscosity reducer is 0.1-0.3%, the viscosity reduction rate of the viscosity reducer on victory thick oil and Liaohe thick oil is more than 95%;

(2) the viscosity reducer can resist thehigh temperature of more than 200 ℃, and can be used as a thick oil viscosity reducer accompanied with steam injection;

(3) the viscosity reducer has a good emulsifying effect on the thick oil without being compounded with alkaline substances, and avoids the damage of the alkaline substances to the stratum.

Claims

1. The high-temperature thick oil viscosity reducer is characterized in that the viscosity reducer is an N-alkyl-gamma-diquaternary ammonium cationic surfactant with a structural general formula of [ RN⁺(CH₃)₂CH₂CH₂CH₂N⁺(CH₃)₃]2Cl^-The molecular weight is 384-468.

2. A preparation method of a high-temperature thick oil viscosity reducer is characterized by mainly comprising the following three steps:

(1) putting aliphatic amine and a catalyst into a three-necked bottle, dropwise adding acrylonitrile at the temperature of 30-60 ℃, and reacting for 4-8 hours to obtain N-alkyl- β -aminopropionitrile;

(2) adding N-alkyl- β -aminopropionitrile and a solvent into an autoclave, replacing air in the autoclave with nitrogen, introducing hydrogen and chlorine, and reacting at 80-90 ℃ for 1-2 hours to prepare N-alkyl propane diamine;

(3) adding N-alkyl propane diamine and a catalyst into an autoclave, replacing air in the autoclave with nitrogen, heating to 60 ℃, introducing methyl chloride, reacting at 80-90 ℃ and 0.49-0.59 MPa for 2-6 hours to obtain the N-alkyl-gamma-bis-quaternary ammonium cationic surfactant, wherein the reaction equation is as follows:

3. the process for producing a high-temperature thick oil viscosity reducer according to claim 2, wherein the aliphatic amine is dodecylamine, hexadecylamine or octadecylamine, preferably hexadecylamine.

4. The process for preparing viscosity reducer of high temperature thick oil according to claim 2, wherein the catalyst is sodium hydroxide or sodium carbonate or triethanolamine, preferably sodium carbonate.

5. The process for producing a high-temperature thick oil viscosity reducer according to claim 2, wherein the solvent is ethanol or isopropanol or butanol, preferably isopropanol.