CN103965848A - Composite profile control agent and preparation method thereof - Google Patents

Abstract

The invention relates to a composite profile control agent prepared from oily sludge and hard asphalt, which comprises the following composition in terms of weight percentage: oily sludge: 10% to 70%; emulsified asphalt: 1% to 20%; surfactant: 1% to 5%; additives: 0% to 1%; the rest is water. The composite profile control agent of the invention has good temperature and salt resistance, high plugging strength, suitable working time, long plugging validity period, low cost, strong practicability and simple preparation method.

Description

A kind of composite profile control agent and preparation method thereof

technical field

The invention relates to the technical fields of oilfield chemistry and oil recovery, in particular to an emulsified asphalt (heavy oil) composite oily sludge profile control agent and a preparation method thereof.

Background technique

Oily sludge refers to a mixture of various forms in which crude oil or refined oil is mixed with soil or other media, and the oil in it cannot be directly recovered and may cause environmental pollution. Oily sludge generally has the characteristics of large production, high oil content, high viscosity, fine particles, and difficult dehydration. The treatment of oily sludge is a difficult problem for major oil fields, but if it stays on the ground, it will bring many hazards. The oily sludge is huge, if it is not treated and discharged directly, it will not only occupy a large amount of cultivated land, but also pollute the surrounding soil, water, and air, accompanied by the generation of foul-smelling gas, and will pollute the surrounding soil, water, and air. Accompanied by the generation of malodorous gas, the sludge contains a large number of pathogenic bacteria, parasites (eggs), heavy metals such as copper, zinc, chromium, mercury, salts, and refractory toxic and harmful substances such as polychlorinated biphenyls, dioxins, and radionuclides. substance. Arbitrary landfilling will lead to serious pollution of groundwater, damage to the original ecology of food crops, and a significant increase in the incidence of regional AIDS in human life.

Due to the complex composition and difficult separation, the treatment and recycling of oily sludge is one of the difficult problems in the research of oilfield chemistry. The indiscriminate discharge of a large amount of oily sludge is harmful to the surrounding environment and human health, and the high fines also burden the entire oil field with a heavy economic burden. In response to this problem, various countermeasures are being actively taken at home and abroad, hoping to alleviate various problems caused by oily sludge. The methods of treating oily sludge at home and abroad generally include incineration, biological treatment, hot washing, solvent extraction, chemical demulsification, solid-liquid separation, coking, and comprehensive utilization of oily sludge.

Chinese patent 03149758.6, Chinese patent 200810249847.8 and Chinese patent 201010245429.9 respectively disclose a profile control agent for oily sludge. They all use oily sludge and water as the main body, and add a small amount of additives to make a profile control agent. Some profile control agents have been tested In practical application, the effect is good. However, the plugging strength of the above-mentioned profile control agents under formation conditions is not enough, and the validity period is short, which increases the secondary cost of profile control. In addition, Chinese Patent No. 201010288718.7 and Chinese Patent No. 201210241537.8 respectively disclose plugging regulators mainly composed of asphalt particles and emulsified asphalt, but the process is complicated and the cost is high, which is not conducive to a wide range of practical applications.

In short, the existing oily sludge profile control agents mainly have problems such as poor plugging effect, insufficient temperature and salt resistance, and short validity period, which will increase the cost of profile control for water injection wells. However, the asphalt plugging control agent with better effect has complicated preparation process and high cost, and is not universally applicable.

Contents of the invention

Aiming at the problems existing in the prior art, the object of the present invention is to provide a method for preparing a composite high-efficiency profile control agent by using oily sludge and emulsified asphalt (heavy oil). High, suitable working time, long sealing validity period, low cost and strong practicability.

The specific technical scheme is as follows:

A composite profile control agent prepared from oily sludge and hard asphalt, comprising the following composition in terms of weight percentage: oily sludge: 10% to 70%; emulsified asphalt: 1% to 20%; surfactant: 1% to 5%; additives: 0%-1%; the balance of water.

On the basis of the above scheme, the softening point of the asphalt used in the emulsified asphalt is 40-130° C., and the viscosity at 100° C. is 2-425 Pa.s.

On the basis of the above scheme, the surfactant is one, two or three of anionic surfactants, nonionic surfactants and cationic surfactants.

On the basis of the above scheme, the anionic surfactant is among tall oil sulfonates, alkyl sulfonates, alkylbenzene sulfonates, alkyl sulfates and lignin sulfonates one or a combination of several.

On the basis of the above scheme, the nonionic surfactant is alkylphenol polyoxyethylene ether, nonylphenol polyoxyethylene ether, aralkylphenol polyoxyethylene ether, polyoxyethylene sorbitan fatty acid One or a combination of esters, sorbitan fatty acid esters, fatty acid polyols and fatty alcohol polyoxyethylene ethers.

On the basis of the above scheme, the cationic surfactant is an alkylamine cationic surfactant, a quaternary ammonium salt cationic surfactant, an amide salt cationic surfactant, an imidazoline cationic surfactant, a cyclic One or more combinations of oxyethylene diamine cationic surfactants and lignin amine cationic surfactants.

On the basis of the above scheme, the auxiliary agent is ammonium salt, calcium salt, strontium salt, water glass, sodium carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, polyacrylamide, polyethylene glycol, One or a combination of polyurethane, guar gum, xanthan gum and bentonite.

A method for preparing the composite profile control agent as described above, the specific steps are as follows:

(1) Weigh each component according to the amount, and heat the oily sludge to room temperature to 90°C;

(2) Add the auxiliary agent into water, dilute and set aside;

(3) Dissolving the surfactant in water at 40°C to 90°C to prepare a solution;

(4) Put the surfactant solution into the container and keep it warm, add the oily sludge, stir, and disperse the oily sludge in the surfactant solution; then add emulsified asphalt and additives to the above solution and fully stir, Cool to room temperature to obtain the finished profile control agent.

The composite profile control agent of the invention has good temperature and salt resistance, high plugging strength, suitable working time, long plugging validity period, low cost, strong practicability and simple preparation method.

Detailed ways

The following examples are only used to further describe the present invention, and are not intended to limit the scope of the present invention.

The experimental methods used in the following examples are conventional methods unless otherwise specified, and the evaluation of the plugging performance of the profile control agent refers to "SY/T5590-2004 Profile Control and Performance Evaluation Methods".

The materials and reagents used in the following examples can be obtained from commercial sources unless otherwise specified.

Embodiment 1～3:

The oily sludge used in the composite profile control agents provided in Examples 1-3 is taken from Gudao Oil Production Plant of Shengli Oilfield, the ionic surfactant is alkylbenzene sulfonate, and the asphalt has a softening point of 86°C (100°C viscosity 425Pa.s) of hard asphalt, the additive is polyacrylamide.

The preparation method of the profile control agent provided by the present embodiment comprises the following steps:

1. Take the oily sludge according to the ratio, and reserve it at room temperature;

2. Add the additive to water, dilute and set aside;

3. Dissolve the surfactant in water at 40°C to make a solution;

4. The asphalt is made into emulsified asphalt by conventional methods;

5. adding the surfactant solution into the container and keeping it warm, adding the oily sludge, and using high-speed shearing equipment to disperse the oily sludge in the surfactant solution;

6. Add emulsified asphalt and additives to the above system, stir well, and cool to room temperature to obtain the finished profile control agent.

The profile control agent prepared above was evaluated, and the results showed that compared with Example 1, Example 2 and Example 3, the pressure during the injection process was lower and the injection was stable. The injection pressure of Example 3 increased relatively quickly, but both Low, continuous injection 2PV pressure maximum is only 0.3MPa. The plugging rates in Examples 1 to 3 were 96%, 94% and 93%, respectively, and the plugging rate did not decrease significantly after water flooding of 100 PV, indicating that the water plugging effect of the profile control agent is ideal.

Table 1 Example 1-3 The proportioning design of the compound profile control agent (percentage by weight, the % balance is water)

Embodiment 4～6:

The oily sludge used in the composite profile control agents provided in Examples 4-6 is taken from Gudao Oil Production Plant of Shengli Oilfield, the surfactant is alkylbenzene sulfonate, and the asphalt has a softening point of 86°C (100°C viscosity is 425Pa.s) of hard asphalt, the auxiliary agent is hydroxyethyl cellulose.

The preparation method of the profile control agent provided by the present embodiment comprises the following steps:

1. Take the oily sludge according to the ratio and heat it to 80°C for later use;

2. Add the additive to water, dilute and set aside;

3. Dissolve the surfactant in water at 60°C according to the ratio to make a solution;

4. The asphalt is made into emulsified asphalt by conventional methods;

5. adding the surfactant solution into the container and keeping it warm, adding the oily sludge, and using high-speed shearing equipment to disperse the oily sludge in the soap solution;

6. Add emulsified asphalt and additives to the above system, stir well, and cool to room temperature to obtain the finished profile control agent.

Evaluation of the profile control agent prepared above shows that preheating to 80°C during the preparation of the plugging agent can significantly reduce the time of shearing and stirring during the preparation process, and the particle size of the dispersed profile control agent is smaller and more stable. Sex is better. The plugging rates in Examples 4 to 6 were 97%, 94% and 94%, respectively, and the plugging rate did not decrease significantly after water flooding of 100 PV, indicating that the water plugging effect of the profile control agent is ideal.

Table 2 Example 4-6 The proportioning design of the compound profile control agent (percentage by weight, the % balance is water)

Embodiment 7～10:

The oily sludge used in the composite profile control agents provided in Examples 7-10 was taken from the Gudao Oil Production Plant of Shengli Oilfield. The surfactants used in Examples 7-10 were anionic surfactants, alkylbenzene sulfonates, non- The mass ratio of ionic surfactant alkylphenol polyoxyethylene ether, cationic imidazoline and alkylbenzene sulfonate to alkylphenol polyoxyethylene ether is 1:1, and the softening point of asphalt is 86°C (100 ℃ viscosity of 425Pa.s) of hard asphalt, the additive is polyethylene glycol.

The preparation method of the profile control agent provided by the present embodiment comprises the following steps:

1. Take the oily sludge according to the ratio and heat it to 80°C for later use;

2. Add the additive to water, dilute and set aside;

3. Dissolve the surfactant in water at 80°C according to the ratio to make a solution;

4. The asphalt is made into emulsified asphalt by conventional methods;

5. adding the surfactant solution into the container and keeping it warm, adding the oily sludge, and using high-speed shearing equipment to disperse the oily sludge in the soap solution;

6. Add emulsified asphalt and additives to the above system, stir well, and cool to room temperature to obtain the finished profile control agent.

The profile control agent prepared above was evaluated. After non-ionic and cationic surfactants were selected in the examples, the dispersion effect of the prepared profile control agent did not change significantly, and the particle size was relatively low, but the average survival time after entering the formation was longer than that of anionic surfactants. The type of surfactant is short and the ability of continuous injection is slightly poor, so it can quickly plug specific formations. The profile control agent prepared by emulsifying and suspending the surfactant obtained by compounding alkylbenzene sulfonate and alkylphenol polyoxyethylene ether with a mass ratio of 1:1 has the advantages of both, with good dispersion effect and easy migration. The ability ratio is also between the two single doses, and the overall performance is better than the two single doses. The plugging rates in Examples 7 to 10 are 95%, 94%, 94% and 96% respectively, and the plugging rate is only slightly reduced after water flooding of 100PV, still above 90%. The profile control agent has a good plugging effect Effect, in the actual operation process, the migration distance and plugging time of the profile control agent can be controlled by adding different types of surfactants to achieve an adjustable and controllable effect.

Table 3 Example 7-10 The proportioning design of the composite profile control agent (percentage by weight, the % balance is water)

Embodiment 11～13:

The oily sludge used in the composite profile control agent provided in this example is taken from the Gudao Oil Production Plant of Shengli Oilfield. .s) hard asphalt, the additives are ammonium salt, calcium salt and strontium salt respectively.

The preparation method of the profile control agent provided by the present embodiment comprises the following steps:

1. Take the oily sludge according to the ratio and heat it to 80°C for later use;

2. Add the additive to water, dilute and set aside;

3. Dissolve the surfactant in water at 90°C according to the ratio to make a solution;

4. The asphalt is made into emulsified asphalt by conventional methods;

5. adding the surfactant solution into the container and keeping it warm, adding the oily sludge, and using high-speed shearing equipment to disperse the oily sludge in the soap solution;

6. Add emulsified asphalt and additives to the above system, stir well, and cool to room temperature to obtain the finished profile control agent.

The profile control agent prepared above was evaluated, and the results showed that with the increase of the amount of oily sludge, the viscosity of the system gradually increased, and the fluidity decreased accordingly, but all of them could be injected into the formation. Although it becomes larger with the increase of the amount of oily sludge. The plugging rates in Examples 10-12 were 94%, 95% and 94%, respectively, and the plugging rate only slightly decreased after water flooding of 100PV, and was still above 90%. The profile control agent has a good plugging effect.

Table 4 The proportioning design of the composite profile control agent in Examples 11-13 (percentage by weight, the % balance is water)

Embodiment 14～16:

The oily sludge used in the composite profile control agent provided in this example is taken from Gudao Oil Production Plant of Shengli Oilfield, the anionic surfactant is alkylbenzene sulfonate, and the asphalt (heavy oil) is Qinhuangdao AH-90 and Shengli Oilfield respectively. The ultra-heavy oil and hard bitumen of Gudao Oil Production Plant have viscosities of 2.8Pa.s, 5.9Pa.s and 425Pa.s at 100°C respectively, and the additive is sodium carboxymethylcellulose.

The preparation method of the profile control agent provided by the present embodiment comprises the following steps:

1. Take the oily sludge according to the ratio and heat it to 80°C for later use;

2. Add the additive to water, dilute and set aside;

3. Dissolve the surfactant in water at 80°C according to the ratio to make a solution;

4. The asphalt is made into emulsified asphalt by conventional methods;

5. adding the surfactant solution into the container and keeping it warm, adding the oily sludge, and using high-speed shearing equipment to disperse the oily sludge in the soap solution;

6. Add emulsified asphalt and additives to the above system, stir well, and cool to room temperature to obtain the finished profile control agent.

The profile control agent prepared above was evaluated. In the examples, the use of different emulsified asphalt (heavy oil) has little effect on the dispersion performance of the system, and the dispersion effect is relatively ideal. The system has low particle size, uniform dispersion, and good continuous injection ability. The plugging rates in Examples 14-16 were 95%, 94% and 97%, respectively, and the plugging rate was only slightly reduced after water flooding of 100 PV, still above 90%. The profile control agent has a good plugging effect. However, the profile control agent obtained by using hard asphalt with a viscosity of 400 Pa.s has better temperature resistance, and the plugging rate is still more than 95% under the simulated formation conditions above 80 °C.

The proportioning design (percentage by weight, % balance is water) of the compound profile control agent of table 5 embodiment 14-16

The used asphalt (heavy oil) performance index of table 6 embodiment 1-16

Table 7 Asphalt (heavy oil) obtained emulsified asphalt (heavy oil) performance index

The oily sludge used in the present invention is all selected from the Gudao Oil Production Plant of Shengli Oilfield, and the relevant properties and particle size analysis are shown in Tables 8 and 9.

The analysis of the properties of the sludge used in Table 8

Table 9 Analysis of particle size of pure oily sludge

Note: D(4,3) is volume average particle size, D(3,2) is surface area average particle size, D50 is 50% particle size range

The above-mentioned detailed description of the compound profile control agent and its preparation method with reference to the examples is illustrative rather than limiting, and several examples can be listed according to the limited scope, so without departing from the general concept of the present invention Changes and modifications should fall within the protection scope of the present invention.

Claims (8)

1. a compounded injectivity profile modifying agents, is characterized in that: according to weight percent meter, comprise following composition: oily sludge: 10%～70%; Emulsified bitumen: 1%～20%; Tensio-active agent: 1%～5%; Auxiliary agent: 0%-1%; The water of surplus.

2. compounded injectivity profile modifying agents according to claim 1, is characterized in that: the softening temperature of described emulsified bitumen pitch used is at 40-130 ℃, and 100 ℃ of viscositys are at 2～425Pa.s.

3. compounded injectivity profile modifying agents according to claim 1, is characterized in that: described tensio-active agent be in aniorfic surfactant, nonionic surface active agent and cationic surfactant a kind of, two or three.

4. compounded injectivity profile modifying agents according to claim 3, is characterized in that: described aniorfic surfactant is one or more the combination in Yatall MA sulfonate, alkyl sulfonates, alkyl benzene sulfonate, alkylsurfuric acid salt and lignin sulfonate.

5. compounded injectivity profile modifying agents according to claim 3, is characterized in that: described nonionic surface active agent is one or more the combination in alkylphenol polyoxyethylene, polyoxyethylene nonylphenol ether, aralkyl phenol polyethenoxy ether, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester, fatty polyol and fatty alcohol-polyoxyethylene ether.

6. compounded injectivity profile modifying agents according to claim 3, is characterized in that: described cationic surfactant is one or more the combination in alkyl amine cats product, quaternary cationic surfactant, amide salt cationoid tensio-active agent, imidazolines cats product, oxyethane Diamines cats product and wooden amine cation tensio-active agent.

7. compounded injectivity profile modifying agents according to claim 1, is characterized in that: described auxiliary agent is one or more the combination in ammonium salt, calcium salt, strontium salt, water glass, Xylo-Mucine, Natvosol, polyvinyl alcohol, polyacrylamide, polyoxyethylene glycol, urethane, guar gum, yellow first glue and wilkinite.

8. a method of preparing compounded injectivity profile modifying agents described in claim 1-7 any one, is characterized in that concrete step is as follows:

(1) take according to quantity each component, oily sludge is heated to room temperature～90 ℃;

(2) auxiliary agent is added to the water, dilution, standby;

(3) tensio-active agent is dissolved in the water of 40 ℃～90 ℃, is mixed with solution;

(4) surfactant soln is added in container and insulation, add described oily sludge, stir, oily sludge is dispersed in surfactant soln; Afterwards emulsified bitumen and auxiliary agent are added in above-mentioned solution and fully stirring, be cooled to room temperature, obtain amendment finished product.