An oil sludge separating agent, a preparation method and application thereof

Abstract

This invention belongs to the technical field of oil sludge separators, specifically relating to an oil sludge separator, its preparation method, and its application. The invention provides an oil sludge separator comprising, by mass percentage, the following raw materials: 0.5-5% nonionic surfactant; 0.5-5% anionic surfactant; 1-8% oil-catching synergist; 0.5-3% inorganic salt; and the balance being water. The oil-catching synergist is a cyclodextrin-modified zeolite material with surface lipophilic modification and chelated iron. This invention's oil sludge separator has a wide range of applications and can treat various types of oily sludge (including land-borne oil sludge, tank bottom oil sludge, oily sludge from oil refineries, etc.). It also has good treatment effects on high-polymer-content oil sludge and aged oil sludge, reducing the residual oil rate to below 1.5 wt% and achieving an oil recovery rate of over 95%.

Description

Technical Field

[0001] This invention belongs to the field of oil sludge separation agent technology, specifically, it relates to an oil sludge separation agent, its preparation method and application. Background Technology

[0002] Oily sludge is one of the main solid wastes generated during oil extraction, storage, transportation, and processing. Oily sludge from oilfield extraction, tank bottom sludge, and oily sludge from refinery wastewater treatment are all classified as hazardous solid waste. Direct discharge without effective treatment will cause serious pollution to soil, groundwater, and the ecological environment.

[0003] Currently, methods for treating oily sludge mainly include solvent extraction, pyrolysis, biological treatment, and thermochemical cleaning. Pyrolysis, particularly high-temperature thermal desorption, can decompose large oil molecules and achieve oil content in the residue meeting the new GB39707-2023 standard. However, the equipment is prone to coking, leading to increased unplanned downtime. Solvent extraction, used in the Shengli Oilfield, can recover diesel components with a purity of up to 92%. However, high solvent loss during extraction and the risk of excessive residual benzene compounds are the main technical bottlenecks hindering its widespread adoption. Biological treatment, using thermophilic bacteria, can further shorten the refining cycle, but the degradation rate of emulsified sludge with a viscosity >4500 mPa·s drops sharply to below 40%. Thermochemical cleaning is widely used due to its relatively simple operation, short treatment cycle, and the ability to recover oil. The core of thermochemical cleaning lies in the selection and formulation of the sludge separating agent.

[0004] Several oil sludge separators have been reported in the prior art. For example, patent document CN103466908A discloses a steel rolling oil sludge cleaning agent, whose components include 1%~2% nonionic surfactant 6501, 1%~3% anionic surfactant LAS, 2%~4% detergent additive, and the balance water. Patent document CN102627380A discloses a highly efficient acidic oil sludge decomposing agent, whose composition includes 1~15% oxidant, 1~10% co-precipitant, 5~30% flocculant, 1~10% surfactant, 0.5~10% demulsifier, 1~10% acidity regulator, and 50~90% water. Furthermore, patent document CN115232681A discloses a tank bottom oil sludge cleaning agent, which is formulated from waste rubber pyrolysis oil, heavy tar, water glass, and nonionic surfactant.

[0005] However, the above-mentioned existing technologies still have the following shortcomings: (1) Most oil sludge separators are mainly composed of surfactants, and their cleaning and separation mechanism for oil droplets and solid phases is simple and the effect is not ideal; (2) Most oil sludge separators have complex components and poor applicability, which is not conducive to industrial production and field application; (3) Some separators need to be used under acidic (pH 2~5) or alkaline conditions, which are highly corrosive to equipment and difficult to treat subsequent wastewater; (4) Existing separators are not effective in separating high-polymer oil sludge and old oil sludge, and the residual oil rate is difficult to reduce to below 2wt%; (5) Some separators contain elements such as phosphorus, which can easily cause secondary pollution problems such as eutrophication of water bodies.

[0006] Therefore, developing an oil sludge separator with multifunctional synergistic effects, high separation efficiency, good applicability, and environmental friendliness is of great practical significance and application value in the field of oil sludge separation. Summary of the Invention

[0007] The purpose of this invention is to provide an oil sludge separator, its preparation method, and its application, so as to achieve the deoiling effect on oil sludge and further reduce the oil content of sludge.

[0008] Therefore, the present invention provides the following technical solution.

[0009] The first aspect of the present invention provides an oil sludge separator, comprising, by mass percentage, the following raw materials: Nonionic surfactants: 0.5-5%; Anionic surfactants: 0.5-5%; Oil-capturing synergist 1-8%; Inorganic salts 0.5~3%; The remainder is water; The oil-capturing synergist is a cyclodextrin-modified zeolite material with chelated iron and modified for surface lipophilicity.

[0010] In a preferred embodiment of the present invention, the preparation method of the cyclodextrin-modified zeolite material with surface lipophilic modification and chelated iron includes the following steps: S1: Dissolve cyclodextrin in an alkaline solution to obtain a cyclodextrin alkaline solution with a concentration of 10~30wt%, then add 2~5% of the cyclodextrin mass of hydroxyl activator and heat to react, to obtain an activated β-cyclodextrin solution; The zeolite was dispersed in the activated β-cyclodextrin solution and ultrasonically treated, then filtered, washed and dried to obtain cyclodextrin-modified zeolite; S2: Mix silane coupling agent, ethanol and deionized water in a volume ratio of 1:(10~30):(10~30) and heat and stir to obtain silane coupling agent hydrolysate; Cyclodextrin-modified zeolite was added to the hydrolysate of silane coupling agent and stirred to react. After the reaction was completed, the mixture was filtered, washed and dried to obtain cyclodextrin-modified zeolite with chelating ability. S3: Under a nitrogen atmosphere, cyclodextrin-modified zeolite with chelating ability is mixed with ferrous acetate solution and stirred to react. After the reaction is completed, the mixture is filtered, washed and dried to obtain cyclodextrin-modified zeolite with chelated iron. S4: The cyclodextrin-modified zeolite with chelated iron is uniformly dispersed in a solvent, and then a lipophilic monomer and an initiator are added. The reaction is carried out at 60~80℃ for 4~6 hours. After the reaction is completed, the mixture is filtered, washed and dried to obtain the cyclodextrin-modified zeolite material with lipophilic surface modification.

[0011] In a preferred embodiment of the present invention, in step S1, the alkaline solution is an aqueous solution of sodium hydroxide and / or potassium hydroxide with a concentration of 20-40 wt%.

[0012] In a preferred embodiment of the present invention, in step S1, the hydroxyl activator is sodium hypochlorite or epichlorohydrin.

[0013] In a preferred embodiment of the present invention, in step S1, the heating reaction conditions are: temperature 50~60℃, time 1~3h.

[0014] In a preferred embodiment of the present invention, in step S1, the zeolite is selected from any one of clinoptilolite, mordenite, anticline, and chalcogenite.

[0015] In a preferred embodiment of the present invention, in step S1, the ultrasonic treatment conditions are: power 200~400W, time 4~8h.

[0016] In a preferred embodiment of the present invention, in step S2, the silane coupling agent is selected from any one of γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

[0017] In a preferred embodiment of the present invention, in step S2, the heating and stirring conditions are: temperature of 80~100℃ and time of 1~4h.

[0018] In a preferred embodiment of the present invention, in step S2, the stirring reaction conditions are: temperature of 60~80℃ and time of 2~4h.

[0019] In a preferred embodiment of the present invention, in step S3, the mass ratio of the chelating cyclodextrin-modified zeolite to ferrous acetate is 1:(4~8).

[0020] In a preferred embodiment of the present invention, in step S3, the stirring reaction conditions are: temperature of 20~40℃ and time of 4~8h.

[0021] In a preferred embodiment of the present invention, in step S4, the solvent is an aqueous ethanol solution with a volume concentration of 70-90%.

[0022] In a preferred embodiment of the present invention, in step S4, the lipophilic monomer is selected from one or more of butyl acrylate, isooctyl acrylate, lauryl acrylate and octadecyl acrylate.

[0023] In a preferred embodiment of the present invention, in step S4, the amount of the lipophilic monomer added is 5 to 10% of the mass of the cyclodextrin-modified zeolite with chelated iron.

[0024] In a preferred embodiment of the present invention, in step S4, the initiator is selected from any one of ammonium persulfate, sodium persulfate, and potassium persulfate.

[0025] In a preferred embodiment of the present invention, in step S4, the amount of the initiator is 0.5 to 1.0% of the amount of the lipophilic monomer.

[0026] In a preferred embodiment of the present invention, the nonionic surfactant is selected from one or more of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, fatty acid methyl ester ethoxylate, polyoxyethylene sorbitan fatty acid ester, and propylene glycol block polyether.

[0027] In a preferred embodiment of the present invention, the anionic surfactant is selected from one or more of sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, sodium α-olefin sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate, and sodium fatty acid.

[0028] In a preferred embodiment of the present invention, the inorganic salt is selected from one or more of sodium chloride, sodium sulfate, calcium chloride, and magnesium sulfate.

[0029] A second aspect of the present invention provides a method for preparing the sludge separator as described above, comprising the following steps: (1) Weigh out the nonionic surfactant, anionic surfactant, oil-catching synergist, inorganic salt and water according to the proportions; (2) Add water to the reaction vessel and heat it to 40~80℃. Add nonionic surfactant and anionic surfactant in sequence under stirring and stir until completely dissolved to obtain surfactant solution; (3) Add oil-catching synergist and inorganic salt to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution; (4) Cool the mixed solution obtained in step (3) to room temperature to obtain the sludge separator.

[0030] In a preferred embodiment of the present invention, in step (2), the heating temperature is 50°C to 70°C and the stirring speed is 100 to 500 rpm.

[0031] A third aspect of the present invention provides an application of the oil sludge separator as described above in the treatment of oily sludge, comprising the following steps: Oily sludge is mixed with water at a mass ratio of 1:1 to 5, an oil-sludge separator is added, the mixture is stirred and treated, and then allowed to stand to separate into layers. The upper oil phase, the middle water phase, and the lower mud and sand phase are collected separately.

[0032] In a preferred embodiment of the present invention, the amount of the oil sludge separator added is 0.1% to 0.5% of the mass of the oily sludge; In a preferred embodiment of the present invention, the stirring conditions are: temperature of 50°C to 80°C and time of 20 min to 60 min; In a preferred embodiment of the present invention, the settling time is 30 to 100 minutes.

[0033] By employing the above technical solution, the present invention has at least the following advantages: (1) The present invention creatively uses cyclodextrin-modified zeolite material with chelated iron modified by surface lipophilic modification as an oil-capturing synergist. When it is used in combination with anionic / nonionic surfactants, the resulting oil sludge separator can have excellent oil sludge separation effect. Zeolite materials possess abundant microporous structures and large specific surface areas, providing numerous active sites, and both the inner and outer surfaces can be loaded with modified functional groups. Cyclodextrins have hollow barrel-shaped structures with multiple hydroxyl groups on their surfaces, and the hydrophobic inclusion of the cavities can capture organic matter. Numerous hydroxyl groups are easily chemically bonded and grafted onto the zeolite surface. Cyclodextrins are activated by hydroxyl activators (sodium hypochlorite or epichlorohydrin) to make their hydroxyl groups more reactive, and then undergo ion exchange and chemical bonding with cations on the zeolite surface to form a stable cyclodextrin modified layer. The amino functional groups introduced after the hydrolysis of silane coupling agents endow the material with the ability to chelate iron ions, achieving stable iron ion loading. Surface oleophilic modification changes the material surface from hydrophilic to hydrophilic-oleophilic, significantly enhancing the affinity and capture ability for oil droplets. Through the synergistic effect of the above-mentioned porous materials, multi-hydroxy organic polymers and metal ion composite surface modification, the resulting oil-capturing synergist can actively capture tiny oil droplets that have been stripped by surfactants but have not yet completely floated to the surface, promote the aggregation and floating separation of oil droplets and the flocculation and sedimentation separation of solid phases, thereby significantly improving the oil-water-solid separation efficiency.

[0034] (3) This invention prepares an oil-capturing synergist through a four-step method (S1-S4), with synergistic effects between each step: Step S1 activates cyclodextrin with a hydroxyl activator, improving the chemical bonding efficiency between cyclodextrin and zeolite; Step S2 introduces chelating groups through hydrolysis of a silane coupling agent, providing a stable chemical anchor for subsequent iron loading; Step S3 completes the chelation loading of iron ions under nitrogen protection, avoiding... The oxidation process; step S4 involves surface lipophilic modification through graft polymerization of lipophilic monomers, endowing the material with the ability to actively capture oil droplets. These four steps are interconnected and indispensable, collectively constituting the complete technical solution of the oil-capturing synergist of this invention. (2) In the oil sludge separator of this invention, the nonionic surfactant and anionic surfactant are combined to form a mixed adsorption film at the oil-water interface, which can more effectively reduce the interfacial tension between oil and water and promote the stripping of oil from the surface of mud and sand. The oil-catching synergist and the two surfactants produce a synergistic effect: after the surfactant strips the oil from the surface of mud and sand, the oil-catching synergist then captures and enriches the dispersed oil droplets, forming larger oil agglomerates and accelerating the floating and separation of oil droplets. The addition of inorganic salts further reduces the solubility of oil droplets in water through the salting-out effect, promoting the aggregation of oil droplets.

[0035] (3) The oil sludge separator of the present invention requires only 4 to 5 functional components in terms of raw material composition. The raw materials are widely available, low in cost, and easy to prepare. It is easy to realize industrial production and on-site promotion and application.

[0036] (4) The oil sludge separator of the present invention can achieve excellent separation effect under neutral to weak alkaline conditions, without the need for strong acid or strong alkali conditions, with low corrosiveness to equipment, low difficulty in subsequent wastewater treatment, and environmentally friendly.

[0037] (5) The oil sludge separator of the present invention has a wide range of applications and can treat various types of oily sludge (including landed oil sludge, tank bottom oil sludge, oily sludge from oil refineries, etc.). It also has a good treatment effect on high polymer content oil sludge and old oil sludge. After treatment, the residual oil rate can be reduced to below 1.5wt%, and the oil recovery rate is above 95%.

[0038] (6) The oil-capturing synergist in this invention can be recycled and reused, reducing the consumption of reagents and lowering the processing cost of oil sludge separation.

[0039] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Detailed Implementation

[0040] To make the technical means, creative features, achieved objectives, and effects of this invention readily understandable, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0041] Unless otherwise specified, the zeolite used in the examples was purchased from Shijiazhuang Taikuang Mineral Products Co., Ltd., and all others were commercially available products.

[0042] Example 1: Oil sludge separator I and its preparation The sludge separator I in this embodiment comprises the following raw materials by weight percentage: fatty alcohol polyoxyethylene ether (AEO-9) 2.5%; sodium dodecylbenzene sulfonate (SDBS) 2.5%; oil-capturing synergist 4.5%; sodium chloride 1.5%; and the balance being water.

[0043] The preparation method of sludge separator I in this embodiment includes the following steps: (1) Preparation of oleoresin-capturing synergist, namely, cyclodextrin-modified zeolite material with surface lipophilic modification and chelated iron: β-cyclodextrin was dissolved in a 30wt% sodium hydroxide aqueous solution to obtain a 20wt% cyclodextrin / sodium hydroxide solution. 3.5% of epichlorohydrin by weight of β-cyclodextrin was added to the obtained cyclodextrin / sodium hydroxide solution and heated at 55℃ for 2h to obtain an activated β-cyclodextrin solution. Zeolite powder with an average particle size of 100 mesh was dispersed in the activated β-cyclodextrin solution and ultrasonically treated at 300W for 6h. After filtration, washing, and drying, cyclodextrin-modified zeolite was obtained. γ-aminopropyltriethoxysilane, ethanol, and deionized water were mixed at a volume ratio of 1:20:20 and heated and stirred at 90℃ for 3h to obtain a γ-aminopropyltriethoxysilane hydrolysate. Cyclodextrin-modified zeolite was added to a γ-aminopropyltriethoxysilane hydrolysate and stirred at 70°C for 3 h. After the reaction was complete, the mixture was filtered, washed, and dried to obtain chelating cyclodextrin-modified zeolite. Under a nitrogen atmosphere, the chelating cyclodextrin-modified zeolite was mixed with a ferrous acetate solution and stirred at 30°C for 6 h, wherein the mass ratio of the chelating cyclodextrin-modified zeolite to ferrous acetate was 1:6. After the reaction was complete, the mixture was filtered, washed, and dried to obtain iron-chelated cyclodextrin-modified zeolite. The cyclodextrin-modified zeolite with chelated iron was uniformly dispersed in an 80% (v / v) aqueous ethanol solution. Then, butyl acrylate (7.5% of the mass of the cyclodextrin-modified zeolite with chelated iron) and ammonium persulfate (0.75% of the butyl acrylate) were added. The mixture was reacted at 75°C for 4 hours. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the cyclodextrin-modified zeolite material with oleophilic surface modification.

[0044] (2) Add water to the reaction vessel and heat to 60°C. Add fatty alcohol polyoxyethylene ether (AEO-9) and sodium dodecylbenzene sulfonate (SDBS) in sequence while stirring at 300 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0045] (3) Add oil-catching synergist and sodium chloride to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution.

[0046] (4) Cool the mixed solution obtained in step (3) to room temperature to obtain sludge separator I.

[0047] Example 2: Sludge Separator II and its Preparation The sludge separator II of this embodiment comprises the following raw materials by weight percentage: 5% dodecylphenol polyoxyethylene ether (OP-10); 0.5% sodium dodecyl sulfate (SDS); 8% oil-capturing synergist; 0.5% sodium sulfate; and the balance being water.

[0048] The preparation method of sludge separator II in this embodiment includes the following steps: (1) Preparation of oleoresin-capturing synergist, namely, cyclodextrin-modified zeolite material with chelated iron modified by surface lipophilic modification: β-cyclodextrin was dissolved in a 40wt% sodium hydroxide aqueous solution to obtain a 10wt% cyclodextrin / sodium hydroxide solution. 2% epichlorohydrin by weight of β-cyclodextrin was added to the obtained cyclodextrin / sodium hydroxide solution and heated at 50℃ for 3h to obtain an activated β-cyclodextrin solution. Zeolite powder with an average particle size of 100 mesh was dispersed in the activated β-cyclodextrin solution and ultrasonically treated at 400W for 4h. After filtration, washing, and drying, cyclodextrin-modified zeolite was obtained. γ-aminopropyltriethoxysilane, ethanol, and deionized water were mixed at a volume ratio of 1:30:10 and heated and stirred at 80℃ for 4h to obtain a γ-aminopropyltriethoxysilane hydrolysate. Cyclodextrin-modified zeolite was added to a γ-aminopropyltriethoxysilane hydrolysate and stirred at 80°C for 2 h. After the reaction, the mixture was filtered, washed, and dried to obtain chelating cyclodextrin-modified zeolite. Under a nitrogen atmosphere, the chelating cyclodextrin-modified zeolite was mixed with a ferrous acetate solution and stirred at 20°C for 8 h, with a mass ratio of chelating cyclodextrin-modified zeolite to ferrous acetate of 1:8. After the reaction, the mixture was filtered, washed, and dried to obtain iron-chelated cyclodextrin-modified zeolite. The cyclodextrin-modified zeolite with chelated iron was uniformly dispersed in a 70% (v / v) aqueous ethanol solution. Then, isooctyl acrylate (5% of the mass of the cyclodextrin-modified zeolite with chelated iron) and potassium persulfate (1.0% of the mass of isooctyl acrylate) were added. The mixture was reacted at 80°C for 4 hours. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the cyclodextrin-modified zeolite material with oleophilic surface modification.

[0049] (2) Add water to the reaction vessel and heat it to 50°C. Add dodecylphenol polyoxyethylene ether (OP-10) and sodium dodecyl sulfate (SDS) in sequence while stirring at 500 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0050] (3) Add oil-catching synergist and sodium sulfate to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution.

[0051] (4) Cool the mixed solution obtained in step (3) to room temperature to obtain sludge separator II.

[0052] Example 3: Sludge Separator III and its Preparation The sludge separator III of this embodiment comprises the following raw materials by weight percentage: fatty alcohol polyoxyethylene ether (AEO-9) 0.5%; sodium dodecylbenzene sulfonate (SDBS) 2%; sodium dodecyl sulfate (SDS) 3%; oil-capturing synergist 1%; sodium chloride 3%; and the balance is water.

[0053] The preparation method of sludge separator III in this embodiment includes the following steps: (1) Preparation of oleoresin-capturing synergist, namely, cyclodextrin-modified zeolite material with surface lipophilic modification and chelated iron: β-cyclodextrin was dissolved in a 20wt% sodium hydroxide aqueous solution to obtain a 30wt% cyclodextrin / sodium hydroxide solution. Epichlorohydrin at 5% of the mass of β-cyclodextrin was added to the obtained cyclodextrin / sodium hydroxide solution and heated at 60℃ for 1h to obtain an activated β-cyclodextrin solution. Zeolite powder with an average particle size of 100 mesh was dispersed in the activated β-cyclodextrin solution and ultrasonically treated at 200W for 8h. After filtration, washing and drying, cyclodextrin-modified zeolite was obtained. N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, ethanol and deionized water were mixed at a volume ratio of 1:10:30 and heated and stirred at 100℃ for 1h to obtain N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane hydrolysate. Cyclodextrin-modified zeolite was added to the hydrolysate of N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane and stirred at 60°C for 4 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain cyclodextrin-modified zeolite with chelating ability. Under a nitrogen atmosphere, the cyclodextrin-modified zeolite with chelating ability was mixed with a ferrous acetate solution and stirred at 40°C for 4 h, wherein the mass ratio of the cyclodextrin-modified zeolite with chelating ability to ferrous acetate was 1:4. After the reaction was completed, the mixture was filtered, washed, and dried to obtain cyclodextrin-modified zeolite with chelated iron. The cyclodextrin-modified zeolite with chelated iron was uniformly dispersed in a 90% (v / v) aqueous ethanol solution. Lauryl acrylate (10% of the mass of the cyclodextrin-modified zeolite with chelated iron) and ammonium persulfate (0.5% of the mass of lauryl acrylate) were added. The mixture was reacted at 75°C for 4 hours. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the cyclodextrin-modified zeolite material with oleophilic surface modification.

[0054] (2) Add water to the reaction vessel and heat it to 70°C. Add fatty alcohol polyoxyethylene ether (AEO-9), sodium dodecylbenzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS) in sequence while stirring at 100 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0055] (3) Add oil-catching synergist and sodium chloride to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution.

[0056] (4) Cool the mixed solution obtained in step (3) to room temperature to obtain sludge separator III.

[0057] Example 4: Sludge Separator IV and its Preparation The sludge separator IV of this embodiment comprises the following raw materials by weight percentage: fatty alcohol polyoxyethylene ether (AEO-9) 2%; dodecylphenol polyoxyethylene ether (OP-10) 2%; sodium dodecylbenzene sulfonate (SDBS) 4%; sodium dodecyl sulfate (SDS) 1%; oil-capturing synergist 6%; sodium sulfate 3%; and the balance is water.

[0058] The preparation method of sludge separator IV in this embodiment includes the following steps: (1) Preparation of oleoresin-capturing synergist, namely, cyclodextrin-modified zeolite material with surface lipophilic modification and chelated iron: β-cyclodextrin was dissolved in a 30wt% sodium hydroxide aqueous solution to obtain a 20wt% cyclodextrin / sodium hydroxide solution. 4% (by weight of β-cyclodextrin) of epichlorohydrin was added to the obtained cyclodextrin / sodium hydroxide solution and heated at 60℃ for 1 h to obtain an activated β-cyclodextrin solution. Zeolite powder with an average particle size of 100 mesh was dispersed in the activated β-cyclodextrin solution and ultrasonically treated at 300W for 6 h. After filtration, washing, and drying, cyclodextrin-modified zeolite was obtained. N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, ethanol, and deionized water were mixed at a volume ratio of 1:30:30 and heated and stirred at 90℃ for 3 h to obtain an N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane hydrolysate. Cyclodextrin-modified zeolite was added to the hydrolysate of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane and stirred at 70°C for 3 h. After the reaction was completed, the mixture was filtered, washed, and dried to obtain cyclodextrin-modified zeolite with chelating ability. Under a nitrogen atmosphere, the cyclodextrin-modified zeolite with chelating ability was mixed with a ferrous acetate solution and stirred at 25°C for 6 h, wherein the mass ratio of the cyclodextrin-modified zeolite with chelating ability to ferrous acetate was 1:5. After the reaction was completed, the mixture was filtered, washed, and dried to obtain cyclodextrin-modified zeolite with chelated iron. The cyclodextrin-modified zeolite with chelated iron was uniformly dispersed in a 70% (v / v) aqueous ethanol solution. Then, octadecyl acrylate (6% of the mass of the cyclodextrin-modified zeolite with chelated iron) and sodium persulfate (0.8% of the mass of octadecyl acrylate) were added. The mixture was reacted at 80°C for 4 hours. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the cyclodextrin-modified zeolite material with oleophilic surface modification.

[0059] (2) Add water to the reaction vessel and heat it to 60°C. Add fatty alcohol polyoxyethylene ether (AEO-9), dodecylphenol polyoxyethylene ether (OP-10), sodium dodecylbenzene sulfonate (SDBS) and sodium dodecyl sulfate (SDS) in sequence while stirring at 200 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0060] (3) Add oil-catching synergist and sodium sulfate to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution.

[0061] (4) Cool the mixed solution obtained in step (3) to room temperature to obtain sludge separator IV.

[0062] Comparative Example 1: Sludge Separator A and its Preparation The oil sludge separator A in this comparative example comprises the following raw materials by weight percentage: fatty alcohol polyoxyethylene ether (AEO-9) 2.5%; sodium dodecylbenzene sulfonate (SDBS) 2.5%; oil-capturing synergist 4.5%; sodium chloride 1.5%; and the balance being water.

[0063] The preparation method of the sludge separator A in this comparative example includes the following steps: (1) Preparation of oleophobic synergist, namely, chelated iron modified zeolite material with surface lipophilic modification: γ-aminopropyltriethoxysilane, ethanol and deionized water were mixed in a volume ratio of 1:20:20 and heated and stirred at 90°C for 3 h to obtain γ-aminopropyltriethoxysilane hydrolysate. Zeolite powder with an average particle size of 100 mesh was added to the γ-aminopropyltriethoxysilane hydrolysate and stirred at 70°C for 3 h. After the reaction was completed, the mixture was filtered, washed and dried to obtain silane-modified zeolite. Under a nitrogen atmosphere, silane-modified zeolite was mixed with ferrous acetate solution and stirred at 30°C for 6 h, wherein the mass ratio of silane-modified zeolite to ferrous acetate was 1:6. After the reaction was completed, the mixture was filtered, washed and dried to obtain chelated iron modified zeolite. The modified zeolite with chelated iron was uniformly dispersed in an 80% (v / v) aqueous ethanol solution. Then, butyl acrylate (7.5% of the mass of the modified zeolite with chelated iron) and ammonium persulfate (0.75% of the mass of butyl acrylate) were added. The mixture was reacted at 75°C for 4 hours. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the modified zeolite material with oleophilic surface modification of chelated iron.

[0064] (2) Add water to the reaction vessel and heat to 60°C. Add fatty alcohol polyoxyethylene ether (AEO-9) and sodium dodecylbenzene sulfonate (SDBS) in sequence while stirring at 300 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0065] (3) Add oil-catching synergist and sodium chloride to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution.

[0066] (4) Cool the mixed solution obtained in step (3) to room temperature to obtain sludge separator A.

[0067] Comparative Example 2: Sludge Separator B and its Preparation The oil sludge separator B in this comparative example comprises the following raw materials by weight percentage: fatty alcohol polyoxyethylene ether (AEO-9) 2.5%; sodium dodecylbenzene sulfonate (SDBS) 2.5%; oil-capturing synergist 4.5%; sodium chloride 1.5%; and the balance being water.

[0068] The preparation method of the sludge separator B in this comparative example includes the following steps: (1) Preparation of oleoresin-modified zeolite material with surface lipophilic modification: β-cyclodextrin was dissolved in a 30wt% sodium hydroxide aqueous solution to obtain a 20wt% cyclodextrin / sodium hydroxide solution. 3.5% of the mass of β-cyclodextrin in epichlorohydrin was added to the obtained cyclodextrin / sodium hydroxide solution and heated at 55℃ for 2h to obtain an activated β-cyclodextrin solution. Zeolite powder with an average particle size of 100 mesh was dispersed in the activated β-cyclodextrin solution and ultrasonically treated at 300W for 6h. After filtration, washing, and drying, cyclodextrin-modified zeolite was obtained. Cyclodextrin-modified zeolite was uniformly dispersed in an 80% (v / v) aqueous ethanol solution. Then, butyl acrylate (7.5% of the mass of the cyclodextrin-modified zeolite) and ammonium persulfate (0.75% of the butyl acrylate mass) were added. The mixture was reacted at 75°C for 4 hours. After the reaction was completed, the mixture was filtered, washed, and dried to obtain a cyclodextrin-modified zeolite material with an oleophilic surface.

[0069] (2) Add water to the reaction vessel and heat to 60°C. Add fatty alcohol polyoxyethylene ether (AEO-9) and sodium dodecylbenzene sulfonate (SDBS) in sequence while stirring at 300 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0070] (3) Add oil-catching synergist and sodium chloride to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution.

[0071] (4) Cool the mixed solution obtained in step (3) to room temperature to obtain sludge separator B.

[0072] Comparative Example 3: Sludge Separator C and its Preparation The oil sludge separator C in this comparative example comprises the following raw materials by weight percentage: fatty alcohol polyoxyethylene ether (AEO-9) 2.5%; sodium dodecylbenzene sulfonate (SDBS) 2.5%; oil-capturing synergist 4.5%; sodium chloride 1.5%; and the balance being water.

[0073] The preparation method of the sludge separator C in this comparative example includes the following steps: (1) Preparation of oil-capturing synergist, namely cyclodextrin-modified zeolite material with chelated iron: β-cyclodextrin was dissolved in a 30wt% sodium hydroxide aqueous solution to obtain a 20wt% cyclodextrin / sodium hydroxide solution. 3.5% of epichlorohydrin by weight of β-cyclodextrin was added to the obtained cyclodextrin / sodium hydroxide solution and heated at 55℃ for 2h to obtain an activated β-cyclodextrin solution. Zeolite powder with an average particle size of 100 mesh was dispersed in the activated β-cyclodextrin solution and ultrasonically treated at 300W for 6h. After filtration, washing, and drying, cyclodextrin-modified zeolite was obtained. γ-aminopropyltriethoxysilane, ethanol, and deionized water were mixed at a volume ratio of 1:20:20 and heated and stirred at 90℃ for 3h to obtain a γ-aminopropyltriethoxysilane hydrolysate. Cyclodextrin-modified zeolite was added to a γ-aminopropyltriethoxysilane hydrolysate and stirred at 70°C for 3 h. After the reaction, the mixture was filtered, washed, and dried to obtain chelating cyclodextrin-modified zeolite. Under a nitrogen atmosphere, the chelating cyclodextrin-modified zeolite was mixed with a ferrous acetate solution and stirred at 30°C for 6 h, with a mass ratio of chelating cyclodextrin-modified zeolite to ferrous acetate of 1:6. After the reaction, the mixture was filtered, washed, and dried to obtain chelated iron cyclodextrin-modified zeolite material.

[0074] (2) Add water to the reaction vessel and heat to 60°C. Add fatty alcohol polyoxyethylene ether (AEO-9) and sodium dodecylbenzene sulfonate (SDBS) in sequence while stirring at 300 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0075] (3) Add oil-catching synergist and sodium chloride to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution.

[0076] (4) Cool the mixed solution obtained in step (3) to room temperature to obtain sludge separator C.

[0077] Comparative Example 4: Sludge Separator D and its Preparation The oil sludge separator D in this comparative example comprises the following raw materials by weight percentage: fatty alcohol polyoxyethylene ether (AEO-9) 2.5%; sodium dodecylbenzene sulfonate (SDBS) 2.5%; oil-capturing synergist 4.5%; sodium chloride 1.5%; and the balance being water.

[0078] The preparation method of the sludge separator D in this comparative example includes the following steps: (1) Add water to the reaction vessel and heat it to 60°C. Add fatty alcohol polyoxyethylene ether (AEO-9) and sodium dodecylbenzene sulfonate (SDBS) in sequence while stirring at 300 rpm. Stir until completely dissolved to obtain a surfactant solution.

[0079] (2) Add oil-catching synergist (zeolite powder with an average particle size of 100 mesh) and sodium chloride to the surfactant solution obtained in step (1), and continue stirring until completely dissolved to obtain a mixed solution.

[0080] (3) Cool the mixed solution obtained in step (2) to room temperature to obtain sludge separator D.

[0081] Comparative Example 5: Sludge Separator E and its Preparation The only difference between this comparative example and Example 1 is that no oil-capturing synergist was added; otherwise, it remained the same as Example 1, resulting in sludge separator E.

[0082] Comparative Example 6: Sludge Separator F and its Preparation The only difference between this comparative example and Example 1 is that sodium dodecylbenzenesulfonate (SDBS) was not added; otherwise, it remained the same as Example 1, resulting in sludge separator F.

[0083] Comparative Example 7: Sludge Separator G and its Preparation The only difference between this comparative example and Example 1 is that sodium dodecylbenzenesulfonate (SDBS) and the oil-capturing synergist were not added; otherwise, the results were the same as in Example 1, yielding sludge separator G.

[0084] Experimental Example 1: Testing the Treatment Effect of Different Oil Sludge Separators on Different Types of Oily Sludge To verify the universality of the oil sludge separator of this invention in treating different types of oily sludge, this experiment selected four representative oily sludge samples and treated them with the oil sludge separators prepared in Examples 1-4 and Comparative Examples 1-7, respectively. The performance of the oil sludge separator was evaluated by measuring the oil recovery rate and the residual oil content in the treated sludge and sand. Specifically, the following content was included: 1. Oily sludge samples and oil-sludge separating agents used in the experiment 1.1 Select the following four types of oily sludge samples: Oil Sample 1: Oily sludge from the bottom of a tank in an oil field, with an oil content of 18.5%, a water content of 32.0%, and a solid content of 49.5%, belonging to aged oily sludge with medium oil content and high water content.

[0085] Sample 2: Oily sludge from a refinery, with an oil content of 22.3%, a water content of 28.5%, and a solid content of 49.2%. It is a refinery sludge with high oil content and containing recalcitrant macromolecular oil.

[0086] Oil Sample 3: Oil sludge from a certain oil field, with an oil content of 15.7%, a water content of 35.0%, and a solid content of 49.3%. It is oil sludge with high sand content and aged oil.

[0087] Oil Sample 4: A polymer-containing oil sludge (polymer flooding produced sludge), with an oil content of 20.6%, a polymer content of approximately 5.2%, a water content of 30.5%, and a solid content of 43.7%. It is a highly viscous, severely emulsified polymer-containing oil sludge.

[0088] 1.2 Oil sludge separator Oil sludge separators I-IV prepared in Examples 1-4 and oil sludge separators A-G prepared in Comparative Examples 1-7.

[0089] 2. Test methods The treatment method for oily sludge is carried out according to the following steps: Mix the oily sludge with water at a mass ratio of 1:3, add 0.3% (by mass) of oily sludge separating agent, stir at 300 rpm for 30 minutes at 65℃, and then let stand for 60 minutes. After standing, the system naturally separates into three layers: the upper layer is the recovered crude oil, the middle layer is the aqueous phase, and the lower layer is mud and sand. Collect each layer separately, determine the residual oil rate using a gravimetric method (Soxhlet extraction method), and calculate the oil recovery rate.

[0090] Oil recovery rate is calculated using the following formula: Oil recovery rate = (mass of recovered oil / total mass of crude oil in oily sludge) × 100% 3. Results and Analysis The treatment effects of different sludge separators on oil samples 1-4 are shown in Tables 1-4 below.

[0091] Table 1. Results of oil recovery rate and residual oil rate after treatment of oil sample 1 by sludge separator. ; Table 2. Results of oil recovery rate and residual oil rate of oil sample 2 after treatment by sludge separator. ; Table 3. Results of oil recovery rate and residual oil rate after treatment of oil sample 3 by sludge separator. ; Table 4. Results of oil recovery rate and residual oil rate of oil sample 4 after treatment by sludge separator. ; The test results in Tables 1 to 4 show that... (1) The oil sludge separators of Examples 1-4 of the present invention showed excellent treatment effects on four different types of oily sludge with different properties. For oil sample 1 (aged oily sludge at the bottom of the tank, with an oil content of 18.5%), the oil recovery rate of Examples 1-4 was 94.8%-97.1%, and the residual oil rate was 1.0%-1.5%; for oil sample 2 (oily sludge from a refinery, with an oil content of 22.3%), the oil recovery rate was 93.9%-96.3%, and the residual oil rate was 1.3%-1.7%; for oil sample 3 (oily sludge that has fallen to the ground, with an oil content of 15.7%), the oil recovery rate was 95.5%-97.6%, and the residual oil rate was 0.8%-1.3%; for oil sample 4 (oily sludge containing polymers, with an oil content of 20.6% and a polymer content of about 5.2%), the oil recovery rate was 92.5%-95.0%, and the residual oil rate was 1.5%-2.0%. The above results show that the oil sludge separator of the present invention has a good treatment effect on various types of oily sludge. Among them, for the polymeric oily sludge, which is recognized in the industry as a difficult type of oily sludge to treat, the oil recovery rate is still over 92%, which fully demonstrates the technical advantages of the present invention.

[0092] (2) The treatment effects of the four oil samples showed a strong correlation with the difficulty of oil sludge treatment: the best treatment effect was achieved for the landed oil sludge (oil sample 3) with the lowest oil content and relatively easy oil separation; the second best was achieved for the tank bottom oil sludge (oil sample 1) with a medium oil content and a certain degree of aging; the treatment difficulty further increased for the refinery oil sludge (oil sample 2) containing recalcitrant macromolecular oil; and the most difficult to treat was the polymer-containing oil sludge (oil sample 4) with a large amount of polymers and severe emulsification, resulting in the lowest oil recovery rate. This pattern was consistently reflected in Examples 1 to 4, proving that the oil sludge separator of the present invention has stable and predictable separation effects on oil sludge with different treatment difficulties.

[0093] (3) Comparing Example 1 with Comparative Examples 1-3, it can be seen that the four-step modification of the oil-capturing synergist (cyclodextrin modification, chelation capacity introduction, iron chelation loading, and surface lipophilic modification) all contribute to the oil recovery rate to varying degrees. Taking oil sample 1 as an example, the oil recovery rate of Comparative Example 1 (without cyclodextrin modification) was 86.6%, which was 10.1 percentage points lower than that of Example 1; the oil recovery rate of Comparative Example 2 (without iron chelation loading) was 90.5%, which was 6.2 percentage points lower than that of Example 1; and the oil recovery rate of Comparative Example 3 (without surface lipophilic modification) was 81.4%, which was 15.3 percentage points lower than that of Example 1. The above data show that surface lipophilic modification contributes the most to the performance of the oil-capturing synergist, followed by cyclodextrin modification, and then iron chelation loading. Although Comparative Example 2 did not undergo iron chelation loading, the oil-catching synergist still exhibited good inclusion, capture, and affinity for oil droplets due to the implementation of both cyclodextrin modification and surface lipophilic modification. Therefore, the oil recovery rate of Comparative Example 2 was higher than that of the other comparative examples. This further illustrates that cyclodextrin modification and surface lipophilic modification constitute the basic functional layer of the oil-catching synergist of this invention, while iron chelation loading plays an auxiliary role in enhancing the coordination of polar substances (such as gums, asphaltenes, etc.).

[0094] (4) Comparing Example 1 with Comparative Examples 4-5, it can be seen that the oil recovery rate of Comparative Example 4 (using unmodified zeolite powder as an oil-catching synergist) for oil sample 1 was 62.2%, while the oil recovery rate of Comparative Example 5 (without adding any oil-catching synergist) was 60.6%, with a difference of only 1.6 percentage points. This indicates that the unmodified zeolite powder basically does not have active oil-catching ability, and may even slightly interfere with the separation process due to the adsorption of some surfactants. However, the oil-catching synergist after the four-step modification treatment of the present invention (Example 1) increased the oil recovery rate to 96.7%, an increase of more than 34 percentage points, which fully demonstrates the significant improvement effect of the modification method of the present invention on the oil-catching performance of zeolite materials.

[0095] (5) Comparing Example 1 and Comparative Example 6, it can be seen that the oil recovery rate of Comparative Example 6 (without the addition of anionic surfactant SDBS) for oil sample 1 was 84.3%, which was 12.4 percentage points lower than that of Example 1, indicating that the absence of anionic surfactant would significantly affect the separation effect. However, its oil recovery rate was still significantly higher than that of Comparative Example 5 (without oil-catching synergist) at 60.6%, indicating that in the system with only nonionic surfactant and oil-catching synergist, the oil-catching synergist can still play an important role in oil catching, reflecting the synergistic effect between the oil-catching synergist and the surfactant.

[0096] (6) Comparative Example 7, lacking both anionic surfactants and oil-catching synergists, achieved an oil recovery rate of only 45.2% for oil sample 1, with a residual oil rate as high as 10.7%; and an oil recovery rate of only 38.9% for oil sample 4 (containing polystyrene sludge), with a residual oil rate as high as 17.3%. Under conditions requiring only nonionic surfactants and inorganic salts, effective deoiling of polystyrene sludge is virtually impossible. This extreme control data serves as a counter-example, demonstrating the indispensability of the synergistic effect of anionic surfactants and oil-catching synergists in this invention.

[0097] Experimental Example 2: Recycling Performance of Oil Capture Synergists The separated middle-layer aqueous phase from Example 1 was filtered to retain the oil-catching synergist particles. The retained particles were washed three times with petroleum ether, then twice with ethanol, and vacuum dried at 60°C for 4 hours, ready for reuse as an oil-catching synergist. Using oil sample 1 as the treatment object, the effect of the number of times the oil-catching synergist was recycled on the oil recovery rate was investigated, and the results are shown in Table 5.

[0098] Table 5. Effect of the number of times the oil-capturing synergist is used on the oil recovery rate. ; As shown in Table 5, after 5 cycles of use, the oil recovery rate of the oil-capturing synergist decreased by only 2.1 percentage points (from 96.7% to 94.6%), and the residual oil rate increased from 1.2 wt% to 1.6 wt%, still maintaining excellent separation effect. This indicates that the oil-capturing synergist of the present invention has good regenerability, which is beneficial to reducing treatment costs in practical applications.

[0099] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the methods and techniques disclosed above without departing from the scope of the present invention to create equivalent embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An oil sludge separator, characterized in that, The raw material composition, expressed as a percentage by mass, includes the following contents: Nonionic surfactants: 0.5-5%; Anionic surfactants: 0.5-5%; Oil-capturing synergist 1-8%; Inorganic salts 0.5~3%; The remainder is water; The oil-capturing synergist is a cyclodextrin-modified zeolite material with chelated iron and modified for surface lipophilicity. The preparation method of the surface-lipophilic modified chelated iron cyclodextrin-modified zeolite material includes the following steps: S1: Dissolve cyclodextrin in an alkaline solution to obtain a cyclodextrin alkaline solution with a concentration of 10~30wt%, then add 2~5% of the cyclodextrin mass of hydroxyl activator and heat to react, to obtain an activated β-cyclodextrin solution; The zeolite was dispersed in the activated β-cyclodextrin solution and ultrasonically treated, then filtered, washed and dried to obtain cyclodextrin-modified zeolite; S2: Mix silane coupling agent, ethanol and deionized water in a volume ratio of 1:(10~30):(10~30) and heat and stir to obtain silane coupling agent hydrolysate; Cyclodextrin-modified zeolite was added to the hydrolysate of silane coupling agent and stirred to react. After the reaction was completed, the mixture was filtered, washed and dried to obtain cyclodextrin-modified zeolite with chelating ability. S3: Under a nitrogen atmosphere, cyclodextrin-modified zeolite with chelating ability is mixed with ferrous acetate solution and stirred to react. After the reaction is completed, the mixture is filtered, washed and dried to obtain cyclodextrin-modified zeolite with chelated iron. S4: The cyclodextrin-modified zeolite with chelated iron is uniformly dispersed in a solvent, and then a lipophilic monomer and an initiator are added. The reaction is carried out at 60~80℃ for 4~6 hours. After the reaction is completed, the mixture is filtered, washed and dried to obtain the cyclodextrin-modified zeolite material with lipophilic surface modification.

2. The sludge separator according to claim 1, characterized in that, In step S1, the alkaline solution is an aqueous solution of sodium hydroxide and / or potassium hydroxide with a concentration of 20-40 wt%. The hydroxyl activator is sodium hypochlorite or epichlorohydrin; The heating reaction conditions are: temperature 50~60℃, time 1~3h.

3. The sludge separator according to claim 1, characterized in that, In step S1, the zeolite is selected from any one of clinoptilolite, mordenite, anticline, and chalcogenite; The ultrasonic treatment conditions are: power 200~400W, time 4~8h.

4. The sludge separator according to claim 1, characterized in that, In step S2, the silane coupling agent is selected from any one of γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane; The heating and stirring conditions are: temperature 80~100℃, time 1~4h; The stirring reaction conditions are: temperature 60~80℃, time 2~4h.

5. The sludge separator according to claim 1, characterized in that, In step S3, the mass ratio of the chelating cyclodextrin-modified zeolite to ferrous acetate is 1:(4~8). The stirring reaction conditions are: temperature 20~40℃, time 4~8h.

6. The sludge separator according to claim 1, characterized in that, In step S4, the solvent is an aqueous ethanol solution with a volume concentration of 70-90%. The lipophilic monomer is selected from one or more of butyl acrylate, isooctyl acrylate, lauryl acrylate, and octadecyl acrylate; The amount of the lipophilic monomer added is 5-10% of the mass of the chelated iron cyclodextrin-modified zeolite.

7. The sludge separator according to claim 1, characterized in that, In step S4, the initiator is selected from any one of ammonium persulfate, sodium persulfate, and potassium persulfate; The amount of the initiator is 0.5 to 1.0% of the amount of the lipophilic monomer.

8. The sludge separator according to claim 1, characterized in that, The nonionic surfactant is selected from one or more of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, fatty acid methyl ester ethoxylate, polyoxyethylene dehydrated sorbitan fatty acid ester, and propylene glycol block polyether. The anionic surfactant is selected from one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, sodium α-olefin sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate, and sodium fatty acid. The inorganic salt is selected from one or more of sodium chloride, sodium sulfate, calcium chloride, and magnesium sulfate.

9. A method for preparing an oil sludge separating agent as described in any one of claims 1 to 8, characterized in that, Includes the following steps: (1) Weigh out the nonionic surfactant, anionic surfactant, oil-catching synergist, inorganic salt and water according to the proportions; (2) Add water to the reaction vessel and heat it to 40~80℃. Add nonionic surfactant and anionic surfactant in sequence under stirring and stir until completely dissolved to obtain surfactant solution; (3) Add oil-catching synergist and inorganic salt to the surfactant solution obtained in step (2), and continue stirring until completely dissolved to obtain a mixed solution; (4) Cool the mixed solution obtained in step (3) to room temperature to obtain the sludge separator.

10. The application of an oil sludge separating agent as described in any one of claims 1 to 8 in the treatment of oily sludge, characterized in that, Includes the following steps: Oily sludge is mixed with water at a mass ratio of 1:1 to 5, oil sludge separation agent is added, the mixture is stirred and treated, and then allowed to stand and separate into layers. The upper oil phase, the middle water phase and the lower mud and sand are collected separately. The amount of the oil sludge separator added is 0.1% to 0.5% of the mass of the oily sludge; The stirring conditions are: temperature 50℃~80℃, time 20min~60min; The settling time is 30~100min.