Oil-based mud demulsifier and preparation method thereof

Abstract

The invention discloses an oil-based mud demulsifier and a preparation method thereof. The oil-based mud demulsifier is prepared from the following raw materials in parts by mass: 20 to 40 parts of polypropylene compound, 10 to 30 parts of polyene polyamine compound, 5 to 10 parts of initiator, 2 to 4 parts of pH (Potential of Hydrogen) regulator and 100 parts of water. The oil-based mud demulsifier provided by the invention has a multi-branched chain structure, and can effectively destroy an interfacial film of waste mud after being added into the waste mud so as to achieve a demulsification effect. The method for preparing the demulsifier is simple and high in demulsification efficiency, and can be applied to treatment of all-oil-based, water-in-oil and synthetic-based waste drilling fluids. Due to a good demulsification effect, the demulsifying agent can also be applied to environment-friendly treatment of waste oil-based mud.

Description

Technical Field

[0001] The invention relates to an oil-based mud demulsifier and a preparation method thereof. Background Art

[0002] As the country pays more and more attention to environmental protection, oilfield production enterprises are required to "zero discharge and zero pollution" of waste fluid during drilling. Therefore, it is becoming more and more important to study the treatment, recovery and utilization of waste oil-based drilling fluid. Waste oil-based drilling fluid mainly contains oil, water, fluid loss reducer, emulsifier, wetting agent and other treatment agents, as well as various drill cuttings, sand and gravel particles generated during drilling. It is very difficult to treat. Only after harmless treatment can it meet environmental protection requirements and be discharged externally.

[0003] Demulsifiers use chemical methods to destroy the high-strength interfacial film at the oil-water interface, thereby reducing the surface tension of the oil-based mud, breaking the stable interfacial structure of the oil-based mud particles, and dispersing them into submicron particles. These particles can then be removed through flocculation, sedimentation, centrifugation and other processes, allowing the waste oil-based mud to be recycled and utilized.

[0004] At present, the commonly used demulsifiers are mostly used for crude oil demulsification, improving crude oil recovery, and demulsification treatment of oilfield wastewater. The development of demulsifiers has also transitioned from sulfonates, cyclopentaneates, and succinate sulfonates to fatty acids, fatty alcohols, and polyoxyethylene ethers, and then to alkyl phenyl ethers, ethylene oxide propylene oxide block copolymers, alkyl imidazoles, alkyl acid resin derivatives, etc. Existing demulsifiers have been widely used in wastewater treatment of oil-containing emulsions in industries such as petroleum, chemical industry, wool spinning, and mechanical processing, as well as in the demulsification of heavy oil and super heavy oil. However, due to the addition of various treatment agents to oil-based mud, the emulsion state is very stable, the demulsification voltage is high, and the demulsification difficulty is great. Summary of the invention

[0005] In order to at least partially solve the above-mentioned technical problems existing in the prior art, an embodiment of the present invention provides an oil-based mud demulsifier with good wetting properties and penetration properties, so as to quickly reach the oil-water interface, destroy the stability of the oil-water interface, and aggregate and condense the dispersed solid phase to achieve the effect of demulsification.

[0006] As one aspect of the present invention, an oil-based mud demulsifier is provided. The demulsifier comprises the following constituent raw materials, measured by mass: 20 to 40 parts of a polypropylene compound, 10 to 30 parts of a polyene polyamine compound, 5 to 10 parts of an initiator, 2 to 4 parts of a pH regulator and 100 parts of water.

[0007] In one or some possible embodiments, the polypropylene compound is polyacrylic acid or polyacrylamide.

[0008] In one or some possible embodiments, the polyene polyamine compound is selected from one or more of diethylenetriamine, triethylenetetramine or tetraethylenepentamine.

[0009] In one or some possible embodiments, the initiator is any commercially available material, and propylene oxide is preferably used in the present invention.

[0010] In one or some possible embodiments, the demulsifier is as shown in formula (I):

[0011]

[0012] In formula (I), the value range of n is 12≤n≤18, and n is an integer; the value range of m is 60≤m≤120, and m is an integer.

[0013] In one or some possible embodiments, the surface tension of the demulsifier does not exceed 25 mN / m.

[0014] As another aspect of the present invention, it relates to a method for preparing the above-mentioned oil-based mud demulsifier, the method comprising the following steps:

[0015] Add a formulated amount of polypropylene compounds, polyene polyamine compounds and initiators into water, mix them, drop a pH regulator into the mixture, raise the temperature, and stir at a certain speed. After the dropwise addition is completed, continue stirring for a certain period of time and then let it stand, age at room temperature, filter, wash, dry, calcine, and grind to obtain an oil-based mud demulsifier.

[0016] In one or some possible embodiments, the temperature is raised to 70-90°C.

[0017] In one or some possible embodiments, the step of adding a pH adjuster to the mixed solution includes: adjusting the pH value of the mixed solution to a range of 7.5 to 8.5.

[0018] In one or some possible embodiments, the pH adjuster may be any alkaline substance, and potassium hydroxide is preferably used in the present invention.

[0019] In one or some possible embodiments, the stirring rate is 500-1000 rpm.

[0020] In one or some possible embodiments, the stirring time is 1 to 2 hours.

[0021] The beneficial effects of the above technical solution provided by the embodiment of the present application include at least:

[0022] 1) The oil-based mud demulsifier of the present invention has a multi-branched structure and can be added to waste mud to effectively destroy the interface film of the waste mud and achieve a demulsification effect.

[0023] 2) The method for preparing the demulsifier of the present invention is simple and has high demulsification efficiency, and can be applied to the treatment of all-oil-based, water-in-oil, and synthetic-based waste drilling fluids. Due to its good demulsification effect, it can also be used in the environmental protection treatment of waste oil-based mud.

[0024] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 The present invention is a reaction flow chart for preparing the oil-based mud demulsifier. DETAILED DESCRIPTION

[0027] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0028] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0029] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which the invention belongs. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0030] In the description of the present invention, it should be noted that the terms "include", "including", "have", "contain" and the like are open terms, meaning including but not limited to.

[0031] Refer to the attached Figure 1 As shown, the preparation of demulsifier in the present invention includes five main steps of stirring reaction, room temperature aging, filtering and cleaning (filtering and washing), drying, and calcining, which specifically include:

[0032] Add polypropylene compounds (monomer 1), polyene polyamine compounds (monomer 2) and initiator into water, stir evenly, add appropriate amount of pH adjuster to the mixture to control the pH value of the mixture between 7.5 and 8.5, heat to 70°C to 90°C, stir at a reaction rate of 500 to 1000 rpm, stir for 1 to 2 hours, let stand after stirring, age at room temperature, filter and wash, dry, calcine and grind to obtain an oil-based mud demulsifier sample.

[0033] Combined with Figure 1 The chemical reaction for preparing the oil-based mud demulsifier of the present invention is as shown in formula (II) or (III):

[0034]

[0035]

[0036] In formula (II) or (III): the value range of n is 12≤n≤18, and n is an integer; the value range of m is 60≤m≤120, and m is an integer.

[0037] The present invention is further described below in conjunction with specific examples, and the protection scope of the present invention is not limited by the following examples. The sources of materials mainly involved in the examples are all conventional commercial products.

[0038] Example 1

[0039] 20 parts of polyacrylamide (monomer 1), 10 parts of diethylenetriamine (monomer 2), and 5 parts of propylene oxide (initiator) were added to 100 parts of distilled water, and stirred evenly to form an aqueous phase. Potassium hydroxide (pH regulator) was then added to control the pH value of the mixed solution between 7 and 8, and the mixture was heated to 70°C and stirred at a stirring rate of 500 rpm for 1 hour, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain a demulsifier p1, as shown in formula (IV):

[0040] Example 2

[0041] 30 parts of polyacrylamide (monomer 1), 20 parts of diethylenetriamine (monomer 2), and 10 parts of propylene oxide (initiator) are added to 100 parts of distilled water, and after stirring evenly to form an aqueous phase, a pH adjuster is added to control the pH value of the mixed solution between 7 and 8, and the mixture is heated to 70°C and stirred at a stirring rate of 500 rpm for 1 hour, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain a demulsifier p2.

[0042] Example 3

[0043] 40 parts of polyacrylamide (monomer 1), 20 parts of triethylenetetramine and 10 parts of diethylenetriamine (monomer 2), 10 parts of propylene oxide (initiator) were added to 100 parts of distilled water, stirred evenly to form an aqueous phase, and then a pH regulator was added to control the pH value between 7 and 8. The mixture was heated to 70° C. and stirred at a stirring rate of 500 rpm for 1 hour, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain a demulsifier p3, as shown in formula (V):

[0044] Example 4

[0045] 20 parts of polyacrylamide (monomer 1), 20 parts of triethylenetetramine (monomer 2), and 5 parts of propylene oxide (initiator) are added to 100 parts of distilled water, stirred evenly to form an aqueous phase, and then a pH adjuster is added to control the pH value between 7 and 8. The mixture is heated to 90° C. and stirred at a stirring rate of 1000 rpm for 2 hours, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain demulsifier p4.

[0046] Example 5

[0047] 30 parts of polyacrylamide (monomer 1), 20 parts of triethylenetetramine (monomer 2), and 5 parts of propylene oxide (initiator) are added to 100 parts of distilled water, stirred evenly to form an aqueous phase, and then a pH adjuster is added to control the pH value between 7 and 8. The mixture is heated to 90° C. and stirred at a stirring rate of 1000 rpm for 2 hours, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain demulsifier p5.

[0048] Example 6

[0049] 40 parts of polyacrylamide (monomer 1), 20 parts of triethylenetetramine (monomer 2), and 10 parts of propylene oxide (initiator) are added to 100 parts of distilled water, and stirred evenly to form an aqueous phase; a pH adjuster is added to control the pH value between 7 and 8, the temperature is raised to 90° C., and stirred at a stirring rate of 1000 rpm for 2 hours, then allowed to stand, aged at room temperature, and then filtered, washed, dried, calcined, and ground to obtain a demulsifier p6.

[0050] Example 7

[0051] 20 parts of polyacrylic acid (monomer 1), 30 parts of triethylenetetramine (monomer 2), and 5 parts of propylene oxide (initiator) were added to 100 parts of distilled water, and stirred evenly to form an aqueous phase. A pH adjuster was added to control the pH value between 7 and 8, and the mixture was heated to 90° C. and stirred at a stirring rate of 1000 rpm for 2 hours, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain demulsifier p7, as shown in formula (VI):

[0052]

[0053] Example 8

[0054] 30 parts of polyacrylic acid (monomer 1), 30 parts of triethylenetetramine (monomer 2), and 5 parts of propylene oxide (initiator) are added to 100 parts of distilled water, stirred evenly to form an aqueous phase, and then a pH adjuster is added to control the pH value between 7 and 8. The mixture is heated to 90° C. and stirred at a stirring rate of 1000 rpm for 2 hours, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain demulsifier p8.

[0055] Example 9

[0056] 40 parts of polyacrylic acid (monomer 1), 30 parts of tetraethylenepentamine (monomer 2), and 10 parts of propylene oxide (initiator) were added to 100 parts of distilled water, and stirred to form an aqueous phase. A pH adjuster was added to control the pH value between 7 and 8, and the mixture was heated to 90° C. and stirred at a stirring rate of 1000 rpm for 2 hours, then allowed to stand, aged at room temperature, filtered, washed, dried, calcined, and ground to obtain a demulsifier p9, as shown in formula (VII):

[0057]

[0058] The inventors also selected a commercially available oily wastewater demulsifier (denoted as b1) from Guangdong Shanmei Environmental Technology Co., Ltd. as a comparative example of the present invention.

[0059] The inventors conducted the following tests on the demulsifiers prepared in the above Examples 1 to 9 and the demulsifier b1 of the comparative example, and recorded the test results in the following Table 1:

[0060] Test 1 Demulsification performance Oil recovery rate determination

[0061] This test was modified according to the demulsification performance test method described in the "Research on Demulsification and Oil Recovery Technology for Oil-in-Water Oil-based Drilling Fluid". The demulsification performance of the prepared demulsifiers P1-P9 was evaluated, and the experimental steps were as follows:

[0062] 1) Take 400 ml of waste oil-based drilling fluid in a mud cup and stir it at 8000 r / min for 20 minutes. Centrifuge the stirred sample at a speed of 4000 r / min for 5 minutes and collect the upper liquid after centrifugation;

[0063] 2) Take 30 ml of the upper liquid after centrifugation of the waste water-in-oil drilling fluid and add it into a 50 ml centrifuge tube;

[0064] 3) Add 0.3g of demulsifier respectively, place the centrifuge tube in a water bath, and heat it in a constant temperature water bath at 50℃ for 1h to demulsify.

[0065] 4) The demulsified sample was centrifuged at a speed of 4000 r / min and a centrifugal time of 5 min, and the oil recovery rate was calculated.

[0066] Test 2: Surface tension measurement

[0067] The surface tension of the demulsifier was measured by using a 1 wt % demulsifier aqueous solution and a BZY-1 fully automatic surface tension meter produced by Shanghai Hengping Instrument Factory.

[0068] Table 1 Demulsifier test results

[0069]

[0070] According to the data in Table 1, it can be seen that the oil recovery rate of the oil-based mud demulsifier prepared by the present invention is not less than 70%, and the oil recovery rate of Example 9 is even as high as 88%. Compared with the comparative example, the demulsifier of the present invention has a good oil recovery rate. In addition, the surface tension of the demulsifier of the present invention does not exceed 25mN / m. Compared with the existing demulsifier, the wettability of the demulsifier of the present invention is far better than that of the existing demulsifier.

[0071] Although the description of the present invention has been quite detailed and has been described in particular with respect to several described embodiments, it is not intended to be limited to any of these details or embodiments or any particular embodiment, so as to effectively cover the intended scope of the present invention. In addition, the present invention is described above with the embodiments foreseeable by the inventors, and its purpose is to provide a useful description, and those non-substantial changes to the present invention that are not currently foreseen may still represent equivalent changes of the present invention.

[0072] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0073] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. Oil-based mud demulsifier, characterized in that: The demulsifier comprises the following raw materials by weight: 20-40 parts of polypropylene compounds, 10-30 parts of polyene polyamine compounds, 5-10 parts of initiators, 2-4 parts of pH regulators and 100 parts of water.

2. The oil-based mud demulsifier according to claim 1, characterized in that: The polypropylene compound is polyacrylic acid or polyacrylamide.

3. The oil-based mud demulsifier according to claim 1, characterized in that: The polyene polyamine compound is selected from one or more of diethylenetriamine, triethylenetetramine or tetraethylenepentamine.

4. The oil-based mud demulsifier according to claim 1, characterized in that: The demulsifier is as shown in formula (I): In formula (I), the value range of n is 12≤n≤18, and n is an integer; the value range of m is 60≤m≤120, and m is an integer.

5. The oil-based mud demulsifier according to claim 1, characterized in that: The surface tension of the demulsifier does not exceed 25 mN / m.

6. A method for preparing the oil-based mud demulsifier according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: Add a formulated amount of polypropylene compounds, polyene polyamine compounds and initiators into water, mix them, drop a pH regulator into the mixture, raise the temperature, and stir at a certain speed. After the dropwise addition is completed, continue stirring for a certain period of time and then let it stand, age at room temperature, filter, wash, dry, calcine, and grind to obtain an oil-based mud demulsifier.

7. The method according to claim 6, characterized in that The temperature is raised to 70-90°C.

8. The method according to claim 6, characterized in that The step of adding a pH adjusting agent to the mixed solution comprises: adjusting the pH value of the mixed solution to a range of 7.5 to 8.

5.

9. The method according to claim 6, characterized in that The stirring rate is 500-1000 rpm.

10. The method according to claim 6, characterized in that The stirring time is 1 to 2 hours.

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