Extracting agent as well as preparation method and application thereof in refining of waste transformer oil

Abstract

The invention discloses an extracting agent and a preparation method and application thereof in waste transformer oil refinement, the extracting agent is composed of a solvent and an additive, the solvent accounts for 80-95% by weight, and the additive accounts for 5-20% by weight; wherein the solvent is a binary compound solvent and comprises a mixed solvent of two of NMP (N-Methyl Pyrrolidone), furfural and dimethyl sulfoxide; the additive comprises one or more of sodium dodecyl benzene sulfonate, sodium ethoxylated alkyl sulfate and sodium dodecyl ether sulfate; when the extracting agent is used for extracting and refining the waste transformer oil, the quality of the obtained regenerated oil product is stable, impurities in the waste transformer oil can be effectively removed, and the quality of the regenerated oil product is stable; when the extraction agent is used for extracting and refining the waste transformer oil, reasonable utilization of waste transformer oil resources can be realized.

Description

Technical Field

[0001] The invention belongs to the technical field of extraction and refining of waste transformer oil, and in particular relates to an extractant and a preparation method thereof and application thereof in the refining of waste transformer oil. Background Art

[0002] With the development of economy and society, the power industry has made rapid progress. With the continuous expansion of power grid, the demand and requirements for transformer oil have also increased significantly. As an important insulating medium in high-voltage power transmission and transformation equipment, transformer oil has the functions of improving insulation strength and heat dissipation performance.

[0003] Transformer oil is a mineral oil composed of aromatic hydrocarbons, cycloalkanes, alkanes and other hydrocarbons. It is an important insulating medium for oil-immersed high-voltage transmission and transformation equipment such as transformers, circuit breakers, current and voltage transformers, bushings, etc. During the long-term operation of the transformer, the transformer oil undergoes a slow chemical reaction under the synergistic effect of multiple factors such as copper, temperature, moisture, oxygen, and electric field. It ages and generates a series of aging products such as hydrogen, sludge, acid products, and low-molecular hydrocarbon gases, which makes the important parameters characterizing aging, such as the acid value, power frequency dielectric loss value, and volume resistivity of the transformer oil, change significantly, and the transformer oil gradually deteriorates.

[0004] According to statistics, my country produces about 60,000 tons of waste transformer oil every year. There are many difficulties in the refining, processing and recycling technology of waste transformer oil. Waste transformer oil contains a large amount of toxic substances. If it is not properly treated, it will cause serious environmental pollution and waste of resources. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0006] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0007] Therefore, the object of the present invention is to overcome the deficiencies in the prior art and provide an extraction agent.

[0008] In order to solve the above technical problems, the present invention provides the following technical solution: the extractant is composed of a solvent and an additive, and the solvent accounts for 80-95% and the additive accounts for 5-20% by weight;

[0009] Wherein, the solvent is a binary compound solvent, including two miscible solvents among NMP, furfural and dimethyl sulfoxide;

[0010] The additives include one or more of sodium dodecylbenzene sulfonate, sodium ethoxylated alkyl sulfate, and sodium dodecyl ether sulfate.

[0011] As a preferred embodiment of the extractant of the present invention, the weight proportion of any component in the binary compound solvent is 40-60%.

[0012] Another object of the present invention is to overcome the deficiencies of the prior art and provide a method for preparing an extractant.

[0013] As a preferred embodiment of the preparation method of the present invention, the solvent and the additive are mixed in a stirred tank and stirred sufficiently to obtain the finished extractant.

[0014] As a preferred embodiment of the preparation method of the present invention, the stirring speed is 500-600 r / min.

[0015] As a preferred embodiment of the preparation method of the present invention, the stirring time is 1 to 2 hours.

[0016] Another object of the present invention is to overcome the deficiencies of the prior art and provide an application of an extractant in the refining of waste transformer oil.

[0017] As a preferred embodiment of the application of the present invention, an extractant is added to a waste transformer oil sample for extraction to obtain regenerated oil.

[0018] As a preferred solution of the application of the present invention, the mass ratio of the waste transformer oil to the extractant is 1:2-5.

[0019] As a preferred solution of the application of the present invention, the waste transformer oil includes gear box oil, air compressor oil and transformer oil.

[0020] Beneficial effects of the present invention:

[0021] 1. The extractant of the present invention is used to extract and purify waste transformer oil, and the obtained regenerated oil product has stable quality, can effectively remove impurities in the waste transformer oil, the dielectric loss factor of the regenerated oil decreases, the acid value decreases, the volume resistivity is improved, and the regenerated oil product has stable quality.

[0022] 2. The extractant of the present invention is used to extract and purify waste transformer oil, and the extraction conditions are mild, which can achieve the rational utilization of waste transformer oil resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0024] Figure 1 It is the untreated waste transformer oil in Examples 1 to 3 of the present invention.

[0025] Figure 2 It is the regenerated oil after the extraction and refining treatment in Examples 1 to 3 of the present invention. DETAILED DESCRIPTION

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0027] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0028] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0029] The raw materials and reagents used in the embodiments of the present invention are as follows: waste transformer oil was provided by Zhanjiang Hongda Petrochemical Co., Ltd., reagents such as NMP, furfural, and dimethyl sulfoxide were purchased from Shanghai Lingfeng Chemical Reagent Co., Ltd., and sodium dodecylbenzene sulfonate, sodium ethoxylated alkyl sulfate, and sodium dodecyl ether sulfate were purchased from Sinopharm Chemical Reagent Co., Ltd.

[0030] Example 1

[0031] This embodiment provides an extractant for refining waste transformer oil, comprising the following effective components in parts by weight: NMP, 95 parts of furfural solvent, and 5 parts of ethoxylated alkyl sodium sulfate additive.

[0032] The preparation method of the extractant 1 comprises:

[0033] Prepare two mixed solvents of NMP and furfural in a weight ratio of 50:50, mix the solvent and the ethoxylated alkyl sodium sulfate additive in a stirring kettle, and stir them for 1 hour at a speed of 500 r / min to obtain the extractant of this example, which is recorded as extractant 1.

[0034] Example 2

[0035] This embodiment provides an extractant for refining waste transformer oil, comprising the following effective components in parts by weight: NMP, 90 parts of dimethyl sulfoxide solvent, and 10 parts of sodium lauryl ether sulfate additive.

[0036] The preparation method of the extractant 2 comprises:

[0037] Prepare two mixed solvents of NMP and dimethyl sulfoxide in a weight ratio of 50:50, mix the solvent and sodium dodecyl ether sulfate additive in a stirring kettle, and stir them for 1 hour at a speed of 500 r / min to obtain the extractant of this example, which is recorded as extractant 2.

[0038] Example 3

[0039] This embodiment provides an extractant for refining waste transformer oil, comprising the following effective components in parts by weight: furfural, 85 parts of dimethyl sulfoxide solvent, and 15 parts of sodium dodecylbenzene sulfonate additive.

[0040] The preparation method of the extractant 3 comprises:

[0041] Prepare two miscible solvents of furfural and dimethyl sulfoxide, mix the solvent and sodium dodecylbenzene sulfonate additive in a stirring kettle, and stir them thoroughly for 1 hour at a speed of 500 r / min to obtain the extractant of this example, which is recorded as extractant 3.

[0042] The extractants prepared in the above three embodiments were added to the waste transformer oil sample at a ratio of 1:3 by weight of waste transformer oil: extractant. The comparison between the regenerated oil after extraction and refining treatment and that before treatment is shown in Table 1.

[0043] Table 1 Comparison of waste transformer oil before and after treatment

[0044]

[0045] Waste transformer oil before treatment Figure 1 As shown, the regenerated oil after extraction and refining in Examples 1 to 3 is as follows Figure 2 As shown, the results show that the regenerated oil obtained after extraction and refining treatment effectively removes impurities in the waste transformer oil, the dielectric loss factor of the regenerated oil is greatly reduced, the acid value is reduced, the volume resistivity is improved, the quality of the regenerated oil is stable, and the refining treatment of the waste transformer oil is effectively realized.

[0046] Example 4

[0047] Take the extractant 2 prepared in the above Example 2 and add it to the waste gearbox oil sample at a ratio of 1:3 by weight of waste gearbox oil: extractant. The comparison between the regenerated oil after extraction and refining treatment and before treatment is shown in Table 2.

[0048] Example 5

[0049] Take the extractant 2 prepared in the above Example 2, add it to the air compressor oil sample in a ratio of 1:3 parts by weight of waste gearbox oil: extractant, and compare the regenerated oil after extraction and refining with that before treatment as shown in Table 2. The viscosity index, acid value, residual carbon, sulfur content, etc. of the waste gearbox oil, waste air compressor oil and regenerated oil are measured according to the reference standards "GB / T1995-1998 Calculation Method for Viscosity Index of Petroleum Products", "GB / T264-1983 Determination Method for Acid Value of Petroleum Products", "SHT0170 Determination Method for Residual Carbon of Petroleum Products", and "GB / T 387-1990 Determination Method for Sulfur Content of Dark Petroleum Products (Tube Furnace Method)".

[0050] Table 2 Comparison of waste gearbox oil and waste air compressor oil before and after treatment

[0051]

[0052] The results show that the viscosity index of the regenerated oil obtained after extraction and refining treatment is increased, the residual carbon value is reduced, the acid value and sulfur content can be effectively reduced, and the quality of the regenerated oil after solvent extraction and refining is improved. The present invention can not only realize the refining treatment of waste transformer oil, but also be applied to the refining treatment of waste gearbox oil, waste air compressor oil and other fields.

[0053] Comparative Example 1

[0054] Using a single solvent NMP as the extractant, the waste gearbox oil: extractant was added to the waste gearbox oil sample in a ratio of 1:3 by weight. The comparison between the regenerated oil after extraction and refining treatment and before treatment is shown in Table 3.

[0055] Comparative Example 2

[0056] Using a single solvent furfural as the extractant, the waste gearbox oil: extractant was added to the waste gearbox oil sample in a ratio of 1:3 by weight. The comparison between the regenerated oil after extraction and refining treatment and before treatment is shown in Table 3.

[0057] Comparative Example 3

[0058] Using a single solvent dimethyl sulfoxide as the extractant, the waste gearbox oil: extractant was added to the waste gearbox oil sample in a ratio of 1:3 by weight. The comparison between the regenerated oil after extraction and refining treatment and before treatment is shown in Table 3.

[0059] Table 3

[0060]

[0061]

[0062] The results show that the viscosity index of the regenerated oil obtained after single solvent extraction and refining treatment is slightly increased, the residual carbon value is reduced, the acid value and sulfur content are also reduced, and the quality of the regenerated oil is also improved, but the improvement effect is not as good as the extractant prepared by the present invention.

[0063] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. An extractant, characterized in that: The extractant is composed of a solvent and an additive, wherein the solvent accounts for 80-95% and the additive accounts for 5-20% by weight; Wherein, the solvent is a binary compound solvent, including two miscible solvents among NMP, furfural and dimethyl sulfoxide; The additives include one or more of sodium dodecylbenzene sulfonate, sodium ethoxylated alkyl sulfate, and sodium dodecyl ether sulfate.

2. The extractant according to claim 1, characterized in that: The weight proportion of any component in the binary compound solvent is 40-60%.

3. The method for preparing the extractant according to claim 1, characterized in that: include, The solvent and the additive are mixed in a stirring kettle and stirred sufficiently to obtain the finished extractant.

4. The preparation method according to claim 3, characterized in that: The stirring speed is 500-600 r / min.

5. The preparation method according to any one of claims 3 or 4, characterized in that: The stirring time is 1 to 2 hours.

6. Use of the extractant according to any one of claims 1 to 2 in the refining of waste transformer oil, characterized in that: The extractant is added into the waste transformer oil sample for extraction to obtain the regenerated oil.

7. The use according to claim 6, characterized in that: The mass ratio of the waste transformer oil to the extractant is 1:2-5.

8. The use according to claim 6, characterized in that: The waste transformer oil includes gear box oil, air compressor oil and transformer oil.

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