Efficient demulsifier for oily sludge and preparation method thereof

Abstract

The invention discloses an efficient demulsifier for oily sludge and a preparation method thereof, and belongs to the technical field of sludge treatment. The preparation method comprises the following steps: dissolving octylphenol polyoxyethylene ether in water, stirring, transferring into a flask, heating to 60 DEG C, adding a peroxide aqueous solution, heating to 80 DEG C under the protection of nitrogen, adding methyl methacrylate, butyl acrylate and an auxiliary agent, keeping the temperature for 30-60 minutes, cooling to 60 DEG C, adding a hydroquinone aqueous solution, and keeping the temperature for 30 minutes to obtain a primary demulsifier; stirring the primary demulsifier, sodium silicate and water to prepare the efficient demulsifier for the oily sludge; the auxiliary agent containing the quaternary ammonium salt structure, methyl methacrylate and butyl acrylate are grafted and crosslinked under the chemical action so as to achieve the synergistic effect, the demulsification effect of the demulsifier is jointly improved, and by means of the combined action of the raw materials such as nonionic demulsifier-octylphenol polyoxyethylene ether, inorganic demulsifier-sodium silicate and hydroquinone, the demulsification effect of the demulsifier is improved. The demulsifier for the sludge has an efficient and stable demulsification effect.

Description

Technical Field

[0001] The invention belongs to the technical field of sludge treatment, and in particular relates to a high-efficiency demulsifier for oily sludge and a preparation method thereof. Background Art

[0002] Oily sludge is a relatively stable suspended emulsion system containing water-in-oil, oil-in-water and suspended solids. Oily sludge has complex components and contains a large amount of organic pollutants such as benzene, phenols, anthracenes, radioactive elements and heavy metal elements. It is listed as a hazardous waste in the "National List of Hazardous Wastes". With the continuous deepening of crude oil exploitation, a large amount of oily sludge is produced every year in major oil fields in my country. At present, the centralized disposal level of oily sludge in my country is low, and the disposal rate of oily sludge is low. If it is not handled properly, it will cause serious secondary pollution to the surrounding soil, water and air, and it is also a great waste of oil resources.

[0003] At present, the main methods for treating oily sludge include water washing, extraction, demulsification, microbial method, etc. Demulsification is a very efficient way to separate oil sludge by reducing the demulsification rate constant, which prevents the combination of droplets. However, the oil recovery rate that can be achieved by demulsifiers used in the prior art needs to be improved. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a high-efficiency demulsifier for oily sludge and a preparation method thereof.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A method for preparing an efficient demulsifier for oily sludge comprises the following steps:

[0007] (1) dissolving octylphenol polyoxyethylene ether in water, stirring for 10-15 minutes, transferring to a three-necked flask, heating to 60° C., slowly adding a peroxide aqueous solution, heating to 80° C. under nitrogen protection, then slowly adding methyl methacrylate, butyl acrylate and an auxiliary agent in sequence, keeping the temperature for 30-60 minutes, finally cooling to 60° C., slowly adding a hydroquinone aqueous solution, keeping the temperature for 30 minutes, and obtaining a primary demulsifier;

[0008] (2) The primary demulsifier, sodium silicate and water are stirred and mixed to prepare a high-efficiency demulsifier for oily sludge.

[0009] Hydroquinone is used as an inhibitor to control the molecular weight distribution of the polymer by slowing down or preventing the formation of free radicals in the polymerization reaction, so that the final demulsifier has better dehydration and deoiling effects. The addition of hydroquinone helps to improve the performance of the demulsifier, ensuring that it can effectively reduce the viscosity of the oil-water interface during application and promote oil-water separation. In addition, the stability and high-efficiency antioxidant properties of hydroquinone also help to improve the overall stability and service life of the demulsifier.

[0010] Furthermore, the step (1) comprises the following raw materials in parts by weight: 0.5-1.5 parts of octylphenol polyoxyethylene ether, 0.12-0.18 parts of peroxide, 2-6 parts of methyl methacrylate, 5-10 parts of butyl acrylate, 1.0-1.5 parts of auxiliary agent, 0.01-0.015 parts of hydroquinone, and 85-100 parts of water.

[0011] Furthermore, the octylphenol polyoxyethylene ether is one or more of octylphenol polyoxyethylene ether-4, octylphenol polyoxyethylene ether-10, octylphenol polyoxyethylene ether-40, and octylphenol polyoxyethylene ether-50.

[0012] Furthermore, the peroxide is one or more of potassium persulfate, sodium persulfate, and ammonium persulfate.

[0013] Furthermore, the auxiliary agent is prepared by the following steps:

[0014] S1. Add glucose methylamine, 5-chloro-1-pentene, triethylamine and DMSO (dimethyl sulfoxide) into a dry three-necked flask under nitrogen protection, stir well and heat to 60°C, keep warm for 3 hours, and distill under reduced pressure after the reaction to obtain intermediate 1; the amount ratio of glucose methylamine, 5-chloro-1-pentene, triethylamine and DMSO is 17.6g:10.2g:16.3mL:120mL;

[0015] Triethylamine is used as an acid binding agent. Under heating, the molar ratio of glucose methylamine and 5-chloro-1-pentene is controlled to be 1:1.05-1.1, and then -NH- of glucose methylamine and -Cl of 5-chloro-1-pentene undergo substitution reaction. The reaction process is as follows:

[0016]

[0017] S2. Under nitrogen protection, add intermediate 1, tetradecane chloride, triethylamine and DMSO into a dry three-necked flask, stir well and heat to 70°C, keep warm for 5 hours, and distill under reduced pressure after the reaction to obtain an auxiliary agent; the dosage ratio of intermediate 1, tetradecane chloride, triethylamine and DMSO is 21.1g:25.1mL:14.5mL:180mL.

[0018] Triethylamine is used as an acid binding agent. Under heating, the molar ratio of intermediate 1 to tetradecane chloride is controlled to be 1:1.1-1.2, and then intermediate 1 and tetradecane chloride undergo a substitution reaction. The reaction process is as follows:

[0019]

[0020] The additive is a quaternary ammonium salt demulsifier, one end of which is a hydrophilic end rich in hydroxyl groups, and the other end is a lipophilic end containing a long carbon chain. At the same time, the additive contains a carbon-carbon double bond, which can react chemically with the carbon-carbon double bonds in methyl methacrylate and butyl acrylate under the action of peroxide. On the one hand, this is beneficial to reducing the strength of the oil-water interface film and increasing the dynamic interfacial activity, thereby showing an excellent demulsification effect. On the other hand, it enables the additive to be fully dispersed and stably exist in the primary demulsifier for a long time, giving full play to the demulsification effect.

[0021] In addition, the addition of sodium silicate produces a synergistic effect between the organic demulsifier and the inorganic demulsifier, thereby making the demulsifier for sludge containing the present invention have a highly efficient and stable demulsification effect.

[0022] Furthermore, in the step (2), the mass ratio of the primary demulsifier, sodium silicate and water is 12-25:0.5-0.8:74-88.

[0023] The invention also discloses a high-efficiency demulsifier for oily sludge, which is prepared according to the preparation method of the high-efficiency demulsifier for oily sludge.

[0024] The beneficial effects of the present invention are as follows: the auxiliary agent containing a quaternary ammonium salt structure has a chemical reaction with methyl methacrylate and butyl acrylate to form graft cross-linking, thereby synergistically improving the demulsification effect of the demulsifier. In addition, due to the synergistic effect between the raw materials such as the non-ionic demulsifier - octylphenol polyoxyethylene ether, the inorganic demulsifier - sodium silicate and hydroquinone, the demulsifier for sludge containing the present invention has a highly efficient and stable demulsification effect. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Example 1

[0027] Preparation of auxiliary agent, the specific steps are as follows:

[0028] S1. Under nitrogen protection, 17.6 g of glucose methylamine, 10.2 g of 5-chloro-1-pentene, 16.3 mL of triethylamine and 120 mL of DMSO were added to a 250 mL dry three-necked flask, stirred thoroughly and heated to 60 °C, and kept warm for 3 h. After the reaction, distillation was carried out under reduced pressure to obtain intermediate 1;

[0029] S2. Under nitrogen protection, add 21.1 g of intermediate 1, 25.1 mL of tetradecane chloride, 14.5 mL of triethylamine and 180 mL of DMSO into a 500 mL dry three-necked flask, stir thoroughly and heat to 70°C, keep warm for 5 hours, and distill under reduced pressure after the reaction to obtain an auxiliary agent.

[0030] Example 2

[0031] Preparation of demulsifier for oily sludge, the specific steps are as follows: 85

[0032] (1) 0.5 parts of octylphenol polyoxyethylene ether-4 was dissolved in 65 parts of water, stirred for 10 minutes, and then transferred to a three-necked flask, heated to 60° C., slowly added 0.12 parts of ammonium persulfate aqueous solution (including 15 parts of water), heated to 80° C. under nitrogen protection, and then slowly added 2 parts of methyl methacrylate, 5 parts of butyl acrylate and 1 part of auxiliary agent in sequence, and kept warm for 30 minutes, and finally cooled to 60° C., slowly added 0.01 parts of hydroquinone aqueous solution (including 5 parts of water), and kept warm for 30 minutes to obtain a primary demulsifier;

[0033] (2) The primary demulsifier, sodium silicate and water are stirred and mixed (the mass ratio of the primary demulsifier, sodium silicate and water is 12:0.5:88) to prepare a demulsifier for oily sludge.

[0034] Example 3

[0035] The specific steps for preparing demulsifier for oily sludge are as follows:

[0036] (1) 1.2 parts of octylphenol polyoxyethylene ether-40 was dissolved in 80 parts of water, stirred for 14 minutes, and then transferred into a three-necked flask, heated to 60° C., 0.16 parts of sodium persulfate aqueous solution (of which water accounted for 10 parts) was slowly added, and heated to 80° C. under nitrogen protection, and then 5 parts of methyl methacrylate, 8 parts of butyl acrylate and 1.3 parts of auxiliary agent were slowly added in sequence, and the temperature was kept for 50 minutes, and finally the temperature was lowered to 60° C., 0.012 parts of hydroquinone aqueous solution (of which water accounted for 5 parts) was slowly added, and the temperature was kept for 30 minutes to obtain a primary demulsifier;

[0037] (2) The primary demulsifier, sodium silicate and water are stirred and mixed (the mass ratio of the primary demulsifier, sodium silicate and water is 20:0.7:80) to prepare a demulsifier for oily sludge.

[0038] Example 4

[0039] The specific steps for preparing demulsifier for oily sludge are as follows:

[0040] (1) Dissolve 1.5 parts of octylphenol polyoxyethylene ether-10 in 85 parts of water, stir for 15 minutes, transfer to a three-necked flask, heat to 60° C., slowly add 0.18 parts of potassium persulfate aqueous solution (of which water has 10 parts), heat to 80° C. under nitrogen protection, then slowly add 6 parts of methyl methacrylate, 10 parts of butyl acrylate and 1.5 parts of auxiliary agent in sequence, keep warm for 60 minutes, finally cool to 60° C., slowly add 0.015 parts of hydroquinone aqueous solution (of which water has 5 parts), keep warm for 30 minutes, and obtain a primary demulsifier;

[0041] (2) The primary demulsifier, sodium silicate and water are stirred and mixed (the mass ratio of the primary demulsifier, sodium silicate and water is 25:0.8:74) to prepare a demulsifier for oily sludge.

[0042] Comparative Example 1

[0043] The specific steps for preparing demulsifier for oily sludge are as follows:

[0044] The remaining steps remain unchanged, only the auxiliary agent in Example 2 is removed to prepare a demulsifier for oily sludge.

[0045] Comparative Example 2

[0046] The specific steps for preparing demulsifier for oily sludge are as follows:

[0047] The remaining steps remain unchanged, only the auxiliary agent in Example 2 is replaced by dodecyl dimethyl benzyl ammonium chloride to prepare a demulsifier for oily sludge.

[0048] Performance Testing

[0049] Weigh 40 parts of oily sludge samples, add 40 parts of water, heat, stir evenly, prepare five parts of oily sludge water samples, add 4 parts of demulsifiers for oily sludge prepared in Examples 2-4 and Comparative Examples 1-2, stir at 80°C for 3h, flotate for 40min, stand for 20min and skim off the upper floating oil, repeat the flotation-standing-skimming steps twice, centrifuge for 10min at a speed of 2500rpm, pour off the upper water layer to obtain the cleaned sludge, and the solid phase oil content after cleaning is shown in the following table:

[0050] Test items Solid phase oil content% Example 2 1.25 Example 3 1.23 Example 4 1.22 Comparative Example 1 1.89 Comparative Example 2 1.61

[0051] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. 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 can be combined in any one or more embodiments or examples in a suitable manner.

[0052] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A method for preparing an efficient demulsifier for oily sludge, characterized in that: The following steps are involved: (1) dissolving octylphenol polyoxyethylene ether in water, stirring for 10-15 minutes, transferring the mixture into a flask, heating the mixture to 60° C., adding a peroxide aqueous solution, heating the mixture to 80° C. under nitrogen protection, adding methyl methacrylate, butyl acrylate and an auxiliary agent, keeping the temperature for 30-60 minutes, cooling the mixture to 60° C., adding a hydroquinone aqueous solution, and keeping the temperature for 30 minutes to obtain a primary demulsifier; (2) stirring the primary demulsifier, sodium silicate and water to prepare a high-efficiency demulsifier for oily sludge; Wherein, the auxiliary agent is prepared by the following steps: S1. Add glucose methylamine, 5-chloro-1-pentene, triethylamine and DMSO into a flask under nitrogen protection, stir and heat to 60°C for 3 h, and distill under reduced pressure to obtain intermediate 1; S2. Under nitrogen protection, add intermediate 1, tetradecane chloride, triethylamine and DMSO into a flask, stir and heat to 70°C for reaction for 5 hours, and distill under reduced pressure to obtain an auxiliary agent.

2. The method for preparing a high-efficiency demulsifier for oily sludge according to claim 1, characterized in that: The usage ratio of glucose methylamine, 5-chloro-1-pentene, triethylamine and DMSO in step S1 is 17.6 g:10.2 g:16.3 mL:120 mL.

3. The method for preparing a high-efficiency demulsifier for oily sludge according to claim 1, characterized in that: The usage ratio of intermediate 1, tetradecane chloride, triethylamine and DMSO in step S2 is 21.1 g: 25.1 mL: 14.5 mL: 180 mL.

4. The method for preparing a high-efficiency demulsifier for oily sludge according to claim 1, characterized in that: The step (1) comprises the following raw materials in parts by weight: 0.5-1.5 parts of octylphenol polyoxyethylene ether, 0.12-0.18 parts of peroxide, 2-6 parts of methyl methacrylate, 5-10 parts of butyl acrylate, 1.0-1.5 parts of auxiliary agent, 0.01-0.015 parts of hydroquinone, and 85-100 parts of water.

5. The method for preparing a high-efficiency demulsifier for oily sludge according to claim 4, characterized in that: The octylphenol polyoxyethylene ether is one or more of octylphenol polyoxyethylene ether-4, octylphenol polyoxyethylene ether-10, octylphenol polyoxyethylene ether-40, and octylphenol polyoxyethylene ether-50.

6. The method for preparing a high-efficiency demulsifier for oily sludge according to claim 4, characterized in that: The peroxide is one or more of potassium persulfate, sodium persulfate and ammonium persulfate.

7. The method for preparing a high-efficiency demulsifier for oily sludge according to claim 1, characterized in that: In the step (2), the mass ratio of the primary demulsifier, sodium silicate and water is 12-25:0.5-0.8:74-88.

8. An efficient demulsifier for oily sludge, characterized in that: The demulsifier is prepared according to the method for preparing a high-efficiency oily sludge demulsifier according to any one of claims 1 to 7.

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