Demulsifier for heavy oil field and preparation method thereof

Abstract

The invention discloses a demulsifier for a heavy oil field and a preparation method of the demulsifier. The preparation method comprises the following steps: reacting an amine compound with benzyl glycidyl ether and allyl glycidyl ether to obtain a multi-aromatic-ring initiator, then polymerizing the multi-aromatic-ring initiator with epoxypropane and ethylene oxide to form a demulsifier polyether, and carrying out crosslinking modification to obtain a multi-aromatic-ring demulsification component A; synthesizing oleylamine polyether, and modifying to generate a dispersing aid component B which contains oil carboxyl and is of a comb-like structure; the demulsifier for the heavy oil field is prepared from the component A and the component B according to the ratio of 6: (1-2). The demulsifier for the heavy oil field prepared by the preparation method has the advantages of low dosing concentration, good dehydration effect, neat dehydration interface and clear dehydrated water.

Description

Technical Field

[0001] The present invention relates to the field of crude oil demulsifiers, and particularly to a demulsifier for viscous oil fields and a preparation method thereof. Background Art

[0002] Crude oil demulsifiers are important chemical agents in crude oil production, gathering and transportation, and refining. Their main function is to cooperate with on-site process equipment to break the emulsified liquid in crude oil and separate the crude oil sewage to meet the water content index after crude oil treatment. Among the numerous methods for realizing the separation of crude oil into oil and water, adding a crude oil demulsifier is a common and most effective method. The composition of crude oil is complex, and there are natural surfactants such as asphaltenes, resins, and paraffins in crude oil. Moreover, with the adoption of various production enhancement measures in oil field production, the complexity of the crude oil emulsion has been further increased. Therefore, the development of targeted demulsifiers is the key to ensuring oil field production.

[0003] At present, the development of demulsifiers mainly focuses on polyethers based on poly(ethylene oxide - propylene oxide) copolymers, as well as their blends and cross - linked modified derivatives. The development of polyethers is the basis of demulsifiers, and the dehydration performance of demulsifiers can be further improved by using certain cross - linking modification methods. For the development of polyethers, the initiator is the key. Currently, the initiators used in demulsifiers are concentrated in higher - carbon alcohols, polyols, polyamines, resin - like substances, etc. However, the content of asphaltenes in the oils of viscous oil fields is high, and there is room for further optimization and improvement in the structure of traditional demulsifiers. Summary of the Invention

[0004] In order to solve the above - mentioned technical problems, the present invention provides a demulsifier for viscous oil fields and a preparation method thereof. The demulsifier has the characteristics of low dosing concentration and good dehydration effect.

[0005] In the first aspect, the present invention provides a preparation method of a demulsifier for viscous oil fields, which is realized by the following technical solutions.

[0006] A preparation method of a demulsifier for viscous oil fields includes the following steps:

[0007] S1. Prepare the multi - benzene - ring demulsifier component A, the main dehydration agent

[0008] a. Place the amine compound in a reaction kettle, and dropwise add benzyl glycidyl ether and allyl glycidyl ether at 50 - 60°C. Control the reaction temperature at 50 - 90°C. After the dropping is completed, raise the temperature to 90 - 100°C and react for 0.5 - 2 hours, then raise the temperature to 120 - 130°C and react for 0.5 - 1.5 hours to obtain a multi - benzene - ring initiator; wherein, the molar ratio of the amine compound, benzyl glycidyl ether, and allyl glycidyl ether is: 1:(N - 1):1, and N is the number of active hydrogens on the nitrogen atom of the organic amine.

[0009] b. React the polycyclic aromatic initiator prepared in step S1a with propylene oxide and ethylene oxide successively under the condition of an alkaline catalyst to obtain a polyether of the polycyclic aromatic initiator. Dissolve the polyether of the polycyclic aromatic initiator in an aromatic solvent, and at 80 - 100 °C, dropwise add an aromatic solution of toluene diisocyanate, where the toluene diisocyanate accounts for 1% - 4% of the mass of the polyether. The dropping time is 0.5 - 1 hour, and the reaction is carried out for 1 - 2 hours to prepare the dehydrating main agent, the polycyclic aromatic demulsifier component A;

[0010] S2. Prepare the dispersion aid component B

[0011] Ⅰ. Use oleylamine as the initiator and react it with propylene oxide and ethylene oxide under the condition of an alkaline catalyst to obtain oleylamine polyether;

[0012] Ⅱ. Dissolve the oleylamine polyether prepared in step S2Ⅰ in an aromatic solvent, add benzoyl peroxide, heat up to 70 - 90 °C, dropwise add acrylic acid, and the dropping time is 30 - 60 minutes. After the dropping is completed, react for 1 - 3 hours to prepare the dispersion aid component B; among them, the mass ratio of oleylamine polyether: aromatic: acrylic acid: benzoyl benzoate is 40 - 60:40 - 60:3 - 10:0.3 - 0.6;

[0013] S3. Mix the dehydrating main agent, the polycyclic aromatic demulsifier component A prepared in step S1 and the dispersion aid component B prepared in step S2 according to a mass ratio of 6:1 - 2 to obtain a demulsifier for viscous oil fields.

[0014] By adopting the above technical solution, due to the high content of asphaltene in the viscous oil field oil products, according to the principle of similar solubility, the demulsifier with a polycyclic aromatic structure has obvious effects in demulsifying viscous oil fields. The present invention further optimizes and enhances the benzene ring structure compared with traditional demulsifiers. The isocyanate cross-linked demulsifier has the characteristic of fast dehydration speed for viscous oil products. The present invention further improves the dehydration effect in viscous oil products through cross-linking modification on the polycyclic aromatic polyether structure. In the present invention, a demulsifying component with a long straight chain and a carboxyl group is preferably selected as the dispersion aid, which has the characteristics of fast dispersion, fast dehydration speed, and strong deep dehydration ability when combined with the main agent.

[0015] Further, in step S1a, the amine compound is selected from one of diethylenetriamine, triethylenetetramine, and tetraethylenepentamine.

[0016] Further, in step S1b, the mass ratio of the polycyclic aromatic initiator to propylene oxide is 1:3 - 199; the mass ratio of ethylene oxide in the polyether is 15 - 50%.

[0017] Further, in step S1b, the reaction temperature of propylene oxide is 140 ± 5 °C, and the reaction pressure < 0.4 MPa; the reaction temperature of ethylene oxide is controlled at 130 ± 5 °C, and the reaction pressure < 0.4 MPa.

[0018] Further, in step S2Ⅰ, the mass ratio of oleylamine to propylene oxide is 1:9 to 59; the mass ratio of ethylene oxide in the polyether is 30 to 50%.

[0019] Further, in step S2Ⅰ, the reaction temperature of propylene oxide is 140 ± 5°C, and the reaction pressure is <0.4 MPa; for ethylene oxide, the controlled reaction temperature is 140 ± 5°C, and the reaction pressure is <0.4 MPa.

[0020] Further, the aromatic solvent is selected as crude C10 aromatic hydrocarbons.

[0021] Further, the basic catalyst is selected as potassium hydroxide or sodium hydroxide.

[0022] In a second aspect, the present invention provides a demulsifier for heavy oil fields, which is achieved by the following technical solutions.

[0023] A demulsifier for heavy oil fields prepared by the above preparation method.

[0024] This application has the following beneficial effects.

[0025] Compared with traditional demulsifiers, the demulsifier for heavy oil fields of the present invention has the characteristics of fast dispersion speed, fast dehydration, and strong deep dehydration ability in heavy oil field demulsifiers. Specific embodiments

[0026] The following further illustrates this patent application in conjunction with examples.

[0027] In the following examples, the materials used in the preparation process are not specially stated and are all purchased through commercial channels without further treatment.

[0028] The crude C10 aromatic hydrocarbons used in the following examples were purchased from Tianjin Hongshun Chemical Co., Ltd.

[0029] Example 1

[0030] A preparation method of a demulsifier for heavy oil fields, comprising the following steps:

[0031] Add 10 g of tetraethylenepentamine into the reaction kettle, heat up to 55 °C, and start to dropwise add 52 g of benzyl glycidyl ether and 6 g of allyl glycidyl ether. Control the reaction temperature at 70 °C. After the dropping is completed, heat up to 90 °C and react for 1 hour, then heat up to 120 °C and react for 1 hour to obtain the initiator I-1. React the synthesized initiator I-1, propylene oxide, and ethylene oxide in a ratio of 1:99:33, and the addition amount of potassium hydroxide is 0.3% of the total amount of polyether. Place the synthesized initiator I-1 and potassium hydroxide in the reaction kettle, heat up to 90 °C and evacuate to dehydrate for 30 minutes. Start to feed propylene oxide at 130 °C, control the reaction kettle at 145 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, evacuate to remove monomers. Then start to feed ethylene oxide, control the reaction kettle at 135 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, cool down, add 0.5% of glacial acetic acid based on the total amount of polyether for neutralization, and evacuate to remove water to obtain polyether BZP-1. Dissolve 46.7 g of polyether BZP-1 in 38.1 g of C10 crude aromatic hydrocarbon solution. At 90 °C, dropwise add the C10 crude aromatic hydrocarbon solution of toluene diisocyanate (1.4 g of toluene diisocyanate dissolved in 10 g of C10 crude aromatic hydrocarbon solvent), and the dropping time is 30 minutes. React for 2 hours to prepare the dehydrated main agent, the polycyclic demulsifier component A-1;

[0032] Place 100 g of oleylamine and 3.6 g of potassium hydroxide in the reaction kettle, heat up to 90 °C and evacuate to dehydrate for 30 minutes. Start to feed 900 g of propylene oxide at 130 °C, control the reaction kettle at 145 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, evacuate to remove monomers. Then start to feed 500 g of ethylene oxide, control the reaction kettle at 135 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, cool down, add 3.75 g of glacial acetic acid for neutralization, and evacuate to remove water to obtain polyether ANP-1. Dissolve the prepared oleylamine polyether ANP-1 in the C10 crude aromatic hydrocarbon solvent, add benzoyl peroxide, heat up to 80 °C, dropwise add acrylic acid, and the dropping time is 30 minutes. After the dropping is completed, react for 2 hours to prepare the dispersing aid component B-1, where the ratio of oleylamine polyether: aromatic hydrocarbon: acrylic acid: benzoyl peroxide is 50:50:5:0.5.

[0033] Mix the polycyclic demulsifier component A-1 and the dispersing aid component B-1 in a ratio of 6:1 to obtain the demulsifier D-1.

[0034] Example 2

[0035] A preparation method of a demulsifier for viscous oil fields includes the following steps:

[0036] Add 10 g of triethylenetetramine to the reaction kettle, heat up to 55 °C, and start dropping 56.1 g of benzyl glycidyl ether and 7.8 g of allyl glycidyl ether. Control the reaction temperature at 70 °C. After the dropping is completed, heat up to 90 °C and react for 1 hour, then heat up to 120 °C and react for 1 hour to obtain the initiator I-2. React the synthesized initiator I-2, propylene oxide, and ethylene oxide in a ratio of 1:59:15, and the addition amount of potassium hydroxide is 0.3%. Place the initiator I-2 and potassium hydroxide in the reaction kettle, heat up to 90 °C and evacuate to dehydrate for 30 minutes. Start feeding propylene oxide at 130 °C, control the reaction kettle at 145 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, evacuate to remove monomers. Then start feeding ethylene oxide, control the reaction kettle at 135 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, cool down, add 0.5% glacial acetic acid for neutralization, and evacuate to remove water to obtain polyether BZP-2. Dissolve 46.7 g of polyether BZP-2 in 38.1 g of C10 rough aromatic hydrocarbon solution. At 90 °C, dropwise add the C10 rough aromatic hydrocarbon solution of tolylene diisocyanate (1.4 g of tolylene diisocyanate dissolved in 10 g of C10 rough aromatic hydrocarbon solvent), and the dropping time is 30 minutes. React for 2 hours to prepare the dehydrated main agent, the polycyclic demulsifier component A-2;

[0037] Place 100 g of oleylamine and 5.8 g of potassium hydroxide in the reaction kettle, heat up to 90 °C and evacuate to dehydrate for 30 minutes. Start feeding 1200 g of propylene oxide at 130 °C, control the reaction kettle at 145 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, evacuate to remove monomers. Then start feeding 650 g of ethylene oxide, control the reaction kettle at 135 °C, and the reaction pressure < 0.4 MPa. After the reaction is completed, cool down, add 6.3 g of glacial acetic acid for neutralization, and evacuate to remove water to obtain polyether ANP-2. Dissolve the prepared oleylamine polyether ANP-2 in the C10 rough aromatic hydrocarbon solvent, add benzoyl peroxide, heat up to 80 °C, and dropwise add acrylic acid. The dropping time is 30 minutes. After the dropping is completed, react for 1.5 hours to prepare the dispersing aid component B-2, where the ratio of oleylamine polyether: aromatic hydrocarbon: acrylic acid: benzoyl peroxide is 45:50:5:0.5.

[0038] Mix the polycyclic demulsifier component A-2 and the dispersing aid component B-2 in a ratio of 5:1 to obtain the demulsifier D-2.

[0039] Example 3

[0040] Mix the polycyclic demulsifier component A-1 and the dispersing aid component B-2 in a ratio of 6:1 to obtain the demulsifier D-3.

[0041] Example 4

[0042] Mix the polycyclic demulsifier component A-2 and the dispersing aid component B-1 in a ratio of 6:1 to obtain the demulsifier D-4.

[0043] Example 5

[0044] The demulsifier D-5 was obtained by mixing the polybenzene ring demulsifier component A-2 and the dispersion aid component B-2 in a ratio of 3:1.

[0045] Performance detection

[0046] For a comprehensive oil sample from a heavy oilfield in the Bohai Sea, at the on-site temperature, the performance of the synthesized demulsifier was evaluated according to the requirements and steps in the "Technical Requirements and Inspection Specifications for Crude Oil Demulsifiers Q / HS2020". The demulsifier water separation amount, water separation speed, water separation color, and water separation interface were observed. The experimental results are shown in Table 1. (The demulsifier currently used in this oilfield is a phenolic amine resin demulsifier)

[0047] Table 1 Oil sample source: heavy oil and water sample from the Bohai Oilfield; mixing method: 120 times; experimental temperature: 75 °C; oil sample volume: 80 ml; water content: 40%

[0048]

[0049] The water separation speed, water separation rate, and water separation color of the heavy oilfield demulsifier prepared in Examples 1-5 of this application have been significantly improved.

[0050] The embodiments of this specific implementation manner are all preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention shall be covered within the protection scope of the present invention.

Claims

1. A method for preparing a demulsifier for heavy oil fields, characterized in that: The following steps are involved: S1. Preparation of dehydration main agent polyphenyl ring demulsifier component A a. placing an amine compound in a reaction kettle, adding benzyl glycidyl ether and allyl glycidyl ether dropwise at 50-60°C, controlling the reaction temperature at 50-90°C, heating to 90-100°C after the addition is completed, reacting for 0.5 to 2 hours, heating to 120 to 130°C, reacting for 0.5 to 1.5 hours, and preparing a multi-benzene ring initiator; wherein the molar ratio of the amine compound, benzyl glycidyl ether and allyl glycidyl ether is: 1:(N-1):1, where N is the number of active hydrogen atoms on the nitrogen atom of the organic amine; b. The polyphenyl ring initiator prepared in step S1a is reacted with propylene oxide and ethylene oxide in succession under alkaline catalyst conditions to obtain a polyphenyl ring initiator polyether, the polyphenyl ring initiator polyether is dissolved in an aromatic hydrocarbon solvent, and an aromatic hydrocarbon solution of toluene diisocyanate is added dropwise at 80 to 100° C., wherein the toluene diisocyanate accounts for 1% to 4% of the mass of the polyether, and the addition is carried out for 0.5 to 1 hour, and the reaction is carried out for 1 to 2 hours to prepare a dehydration main agent polyphenyl ring demulsifier component A; S2. Preparation of dispersing aid component B Ⅰ. Using oleylamine as an initiator to react with propylene oxide and ethylene oxide under alkaline catalyst conditions to prepare oleylamine polyether; Ⅱ. Dissolve the oleylamine polyether prepared in step S2Ⅰ in an aromatic hydrocarbon solvent, add benzoyl peroxide, raise the temperature to 70-90°C, add acrylic acid dropwise for 30-60 minutes, and react for 1-3 hours after the addition is completed to obtain a dispersing aid component B; wherein the mass ratio of oleylamine polyether: aromatic hydrocarbon: acrylic acid: benzoic acid peroxide is 40-60:40-60:3-10:0.3-0.6; S3. The dehydrating main agent polybenzene ring demulsifier component A obtained in step S1 and the dispersing aid component B obtained in step S2 are mixed in a mass ratio of 6:1 to 2 to obtain a demulsifier for heavy oil fields.

2. The method for preparing a demulsifier for heavy oil fields according to claim 1, characterized in that: In step S1a, the amine compound is selected from one of diethylenetriamine, triethylenetetramine and tetraethylenepentamine.

3. The method for preparing a demulsifier for heavy oil fields according to claim 1, characterized in that: In step S1b, the mass ratio of the polyphenyl ring initiator to propylene oxide is 1:3-199; the mass ratio of ethylene oxide to polyether is 15-50%.

4. The method for preparing a demulsifier for heavy oil fields according to claim 1, characterized in that: In step S2Ⅰ, the mass ratio of oleylamine to propylene oxide is 1:9-59; the mass ratio of ethylene oxide to polyether is 30-50%.

5. A demulsifier for heavy oil fields prepared by the preparation method according to any one of claims 1 to 4.

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