CN106281286B

CN106281286B - Foaming agent and preparation method thereof

Info

Publication number: CN106281286B
Application number: CN201510362213.3A
Authority: CN
Inventors: 周国华; 王友启; 马涛; 许关利; 刘平; 谭中良
Original assignee: China Petroleum and Chemical Corp; Sinopec Exploration and Production Research Institute
Current assignee: China Petroleum and Chemical Corp; Sinopec Exploration and Production Research Institute
Priority date: 2015-06-26
Filing date: 2015-06-26
Publication date: 2020-02-21
Anticipated expiration: 2035-06-26
Also published as: CN106281286A

Abstract

The invention discloses a foaming agent and a preparation method thereof. Uniformly mixing 10-50 wt% of alkylbenzene sulfonate metal salt, 50-80 wt% of auxiliary agent alkyl alcohol ether, 5-15 wt% of alkaline inorganic salt and water according to a certain proportion at 30-70 ℃, stirring for about 30 minutes, and stopping heating and stirring to room temperature to obtain the required foaming agent product. At 70 ℃, the mineralization degree of 6700mg/L, the concentration of the foaming agent is 0.5 percent, the foaming capacity is 410ml, and the half-life period is 180 minutes; the oil-water interfacial tension can be reduced to 6.88 multiplied by 10 when tested by a 70 ℃ island simulation oil-water TX-500C rotating drop interfacial tension meter^‑3mN/m。

Description

Foaming agent and preparation method thereof

Technical Field

The invention relates to a chemical for oilfield development, in particular to a low-tension foaming agent and a preparation method thereof, which are used for the fields of chemical agent synthesis, evaluation, oilfield tertiary oil recovery and the like.

Background

The main advantage of foam flooding for improving the recovery ratio is that the displacement system can greatly improve swept volume and block water without blocking oil, and the main work content of indoor experimental research is to research and develop a foaming agent system with strong foaming capacity. With the deep development of research, a foaming agent system capable of improving swept volume and oil washing efficiency is the direction of indoor experimental effort, and the method for reducing interfacial tension on the basis of the research of improving the recovery ratio by using the ASP flooding is to reduce the interfacial tension of an oil-water system of a specific oil reservoir to 10^-3mN/m, there are many chemical formulas to achieve the effect, but give consideration to economic benefit and actual oil reservoir conditions of a mine field, and most of the applied formulas are that an anionic surfactant is used as a main agent and an alkali, an alcohol, a nonionic surfactant and other auxiliaries are added; in combination with the formulation of the foamIn the process, it is found that many of the auxiliaries which contribute to the reduction of the interfacial tension are defoamers, which can not only have good foaming capacity (foaming capacity, half-life) but also reduce the interfacial tension (10)^-3mN/m) of the foaming agent with low interfacial tension.

The low interfacial tension foam composite flooding is originally proposed by Daqing oil fields which firstly develop ASP (active-drainage) composite flooding to improve the recovery efficiency in China, and the low interfacial tension foam composite flooding is formed by adding gas on the basis of ASP (active-drainage) composite flooding so as to enhance the capability of polymer for expanding swept volume. The victory oil field also provides a low-tension foam composite flooding system on the basis of binary composite flooding, wherein a foaming agent formula is formed by compounding two foaming agents with different properties. For a formulation system, the simpler the formulation components, the cheaper the chemical agent can be to function is the highest pursuit.

The ultra-low interfacial tension foam composite flooding developed on the basis of Daqing ternary composite flooding has the alkali content of 1.2 percent in the injection main section plug formula, has serious alkali scaling phenomenon, and can not realize normal injection in an oil reservoir with slightly high calcium and magnesium contents in formation water. The oil-water interfacial tension is reduced on the basis of foam flooding, and the problem of how to reduce the interfacial tension becomes a difficulty in formula development because strong alkali cannot be added into a formula, and the oil-water interfacial tension reducing capability of many surfactants is poor although the foaming capability is good. Surfactants such as gemini surfactants, which have both reduced interfacial tension and better foaming ability, have also been available in some laboratory product developments, but at higher costs.

Disclosure of Invention

The invention provides a high-efficiency and low-cost oil reservoir which is compounded by 2-3 industrial products, is suitable for conventional oil reservoir conditions (45-85 ℃), and can reduce the interfacial tension to 10 DEG C^-3A foaming agent capable of foaming at mN/m.

It is an object of the present invention to provide a low tension foamable composition comprising the reaction product of:

(1) a metal salt of an alkylbenzenesulfonic acid;

(2) an alkyl alcohol ether;

(3) a more basic inorganic salt;

(4) water;

the metal salt of an alkylbenzenesulfonic acid as the component (1) has the general formula R-C₆H₄-SO₃X, wherein R is 12-18 alkane, X is alkali metal, preferably sodium or ;

the alkyl alcohol ether in the component (2) has a general formula of R' O (CH)₂CH₂O) nH, wherein R' is 12-18 alkane;

the alkaline inorganic salt in the component (3) is selected from strong base weak acid salt NaHCO₃、Na₂CO₃、Na₃PO₄、NaH₂PO₄、Na₂HPO₄Or some more basic chelate salts, such as sodium citrate;

the feeding ratio of various reactants is 10-50 wt% of metal salt of alkyl benzene sulfonic acid, 50-80 wt% of alkyl alcohol ether, 5-15 wt% of alkaline inorganic salt and the balance of water. The optimal mixture ratio (mass concentration ratio) of the four reactants is 10: 30: 3: 7.

metal salts of alkylbenzenesulfonic acid are anionic surfactants, which act as blowing agents; the alkyl alcohol ether is a nonionic surfactant and is used as an auxiliary agent; the more basic inorganic salt is used to control the pH of the formulated solution to about 9 and helps to raise the cloud point temperature of the adjuvant.

The second purpose of the invention is to provide a preparation method of a low-tension foaming agent, which comprises the following steps: uniformly mixing 10-50 wt% of alkylbenzene sulfonate metal salt, 50-80 wt% of alkyl alcohol ether, 5-15 wt% of alkaline inorganic salt and water at the temperature of 30-70 ℃, stirring for about 30 minutes, and stopping heating and stirring to room temperature to obtain the required foaming agent product.

The foaming agent of the invention has the following beneficial effects: high efficiency and low cost, and can reduce interfacial tension to 10^-3The mN/m can be foamed, and the method is suitable for improving the recovery ratio of the conventional oil reservoir (the temperature range is 45-85 ℃) by foam flooding. Through evaluation of foaming capacity of a Roche foam instrument, the foaming capacity is 410ml and the half-life period is 180 minutes under the conditions that the concentration of a foaming agent is 0.5%, the temperature is 70 ℃ and the mineralization degree is 6700 mg/L; temperature 7The oil-water interfacial tension can be reduced to 6.88 multiplied by 10 by testing an island simulation oil-water TX-500C rotating drop interfacial tension meter under the conditions of 0 ℃ and 6700mg/L mineralization degree^-3mN/m。

Detailed Description

The present invention is illustrated by the following examples, which should not be construed as limiting the scope of the invention.

The test method comprises the following steps:

a Roche foam meter: Ross-Miles 2152 foam instrument

Example 1

Adding 100g of sodium hexadecylbenzene sulfonate into a reaction kettle, starting a stirrer, keeping the temperature at 30-70 ℃, adding 70g of distilled water while stirring, adding 30g of disodium hydrogen phosphate to adjust the pH value of the solution to be about 9, finally adding 300g of fatty alcohol-polyoxyethylene ether, wherein the specific compound is AEO-9, and stopping heating and stirring after the mixture is fully and uniformly mixed. And (4) cooling to room temperature to obtain a foaming agent product.

The performance test data is as follows: the concentration of the foaming agent is 0.5%, the foaming capacity is 410ml under the conditions of 70 ℃ and the mineralization degree of 6700mg/L, and the half-life period is 180 minutes; the oil-water interfacial tension can be reduced to 6.88 multiplied by 10 by testing the oil-water interfacial tension by an island simulation oil-water TX-500C rotating drop interfacial tension meter under the conditions that the temperature is 70 ℃ and the mineralization degree is 6700mg/L^-3mN/m。

Example 2

Adding 200g of sodium hexadecylbenzene sulfonate into a reaction kettle, starting a stirrer, keeping the temperature at 30-70 ℃, adding 200g of fatty alcohol-polyoxyethylene ether while stirring, wherein the specific compound is AEO-9, finally adding 50g of disodium hydrogen phosphate to adjust the pH value of the solution to be about 9, and stopping heating and stirring after the solution is fully and uniformly mixed. And (4) cooling to room temperature to obtain a foaming agent product.

The data for the performance test are as follows: the concentration of the foaming agent is 0.5%, the foaming capacity is 400ml under the conditions of 70 ℃ and the mineralization degree of 6700mg/L, and the half-life period is more than 300 minutes; the oil-water interfacial tension can be reduced to 6.46 multiplied by 10 when tested by an island simulation oil-water TX-500C rotating drop interfacial tension meter under the conditions that the temperature is 70 ℃ and the mineralization degree is 6700mg/L^-2mN/m。

Example 3

Adding 50g of sodium hexadecylbenzene sulfonate into a reaction kettle, starting a stirrer, keeping the temperature at 30-70 ℃, adding 225g of distilled water while stirring, adding 75g of disodium hydrogen phosphate to adjust the pH value of the solution to be about 9, finally adding 150g of fatty alcohol-polyoxyethylene ether, wherein the specific compound is AEO-9, and stopping heating and stirring after the mixture is fully and uniformly mixed. And (4) cooling to room temperature to obtain a foaming agent product.

The data for the performance test are as follows: the concentration of the foaming agent is 0.5%, the foaming capacity is 420ml under the conditions of 70 ℃ and the mineralization degree of 6700mg/L, and the half-life period is 100 minutes; the oil-water interfacial tension can be reduced to 9 multiplied by 10 by testing an island simulation oil-water TX-500C rotating drop interfacial tension meter under the conditions that the temperature is 70 ℃ and the mineralization degree is 6700mg/L^-3mN/m。

Claims

1. A foamable composition, wherein the foamable composition is prepared by a process comprising the steps of:

adding 200g of sodium hexadecylbenzene sulfonate into a reaction kettle, starting a stirrer, keeping the temperature at 30-70 ℃, adding 200g of fatty alcohol-polyoxyethylene ether AEO-9 while stirring, finally adding 50g of disodium hydrogen phosphate to adjust the pH value of the solution to 9, and stopping heating and stirring after the solution is fully and uniformly mixed; and (4) cooling to room temperature to obtain a foaming agent product.

2. A process for preparing a foamable composition according to claim 1, wherein the process comprises the steps of: adding 200g of sodium hexadecylbenzene sulfonate into a reaction kettle, starting a stirrer, keeping the temperature at 30-70 ℃, adding 200g of fatty alcohol-polyoxyethylene ether AEO-9 while stirring, finally adding 50g of disodium hydrogen phosphate to adjust the pH value of the solution to 9, and stopping heating and stirring after the solution is fully and uniformly mixed; and (4) cooling to room temperature to obtain a foaming agent product.