1540results about "Non-miscible liquid separation" patented technology

A disk-pack turbine for use, for example, in systems and methods in at least one embodiment for separating fluids including liquids and gases into subcomponents by passing the fluid through a fluid intake chamber into an expansion chamber and then through at least a portion of a waveform pattern present between at least two rotors and / or disks. The rotors and / or disks having waveform patterns on at least one side.

The invention discloses a phase splitting device and application thereof in phase splitting treatment of a carbon capture two-phase absorbent. The phase splitting device comprises a shell, an inlet, a lower phase outlet and an upper phase outlet, a pre-split-phase chamber, a split-phase chamber and a separation chamber which are communicated in sequence are arranged in the shell; the pre-phase-splitting chamber comprises a swirler and a rectifying plate; the split-phase chamber comprises a split-phase reinforcing plate and a rotary fixing frame; a hydrophilic material, a hydrophobic material or a combination thereof is arranged on the surface of the split-phase reinforcing plate; and the included angle between the split-phase reinforcing plate and the horizontal plane is 30-75 degrees. By arranging the pre-phase-splitting chamber, the phase-splitting chamber and the separation chamber, a phase-splitting liquid can achieve a good pre-separation effect in the pre-phase-splitting chamber and stably enters the phase-splitting chamber, and then efficient and rapid phase splitting is achieved through treatment of a specific phase-splitting reinforcing plate in the phase-splitting chamber; and the device has the advantages of small volume, compact structure, low investment cost and the like, and particularly has important significance on stable operation of the carbon capture two-phase absorbent.

A disk-pack turbine for use, for example, in systems and methods in at least one embodiment for separating fluids including liquids and gases into subcomponents by passing the fluid through a vortex chamber into an expansion chamber and then through at least a portion of a waveform pattern present between at least two rotors and / or disks. The rotors and / or disks having waveform patterns on at least one side. In at least one embodiment, the waveform patterns include a plurality of hyperbolic waveforms travelling around an axial center of the disk with each hyperbolic waveform having a varying diameter along the waveform.

A disk-pack turbine for use, for example, in systems and methods in at least one embodiment for separating fluids including liquids and gases into subcomponents by passing the fluid through a vortex chamber into an expansion chamber and then through at least a portion of a waveform pattern present between at least two rotors and / or disks. The rotors and / or disks having waveform patterns on at least one side. In at least one embodiment, the waveform patterns include a plurality of hyperbolic waveforms axially aligned around a horizontal center of the system.

The invention discloses a two-dimensional bionic multi-stage conical flow divider for laser processing and an application device thereof, and the two-dimensional bionic multi-stage conical flow divider is characterized in that the upper surface and the lower surface of the two-dimensional bionic multi-stage conical flow divider are provided with micro-groove structures, and the micro-groove structures are longitudinal parallel grooves distributed in a linear array; the two-dimensional bionic multistage cone flow divider is of a bilateral symmetry structure and specifically comprises a single primary main cone and a plurality of secondary small cones on the single side, the secondary small cones are distributed on the two sides of the primary main cone at equal intervals, and the included angle between each secondary small cone and the primary main cone ranges from 9 degrees to 21 degrees. The cone angle of the first-stage main cone structure is 9-21 degrees, the length of the first-stage main cone structure is 8-12 mm, the cone angle of the second-stage small cone structure is 9-21 degrees, the length of the second-stage small cone structure is 1-3 mm, the depth of the micro-groove structure is 35-45 micrometers, and the center-to-center distance of the micro-groove structure is 28-35 micrometers. According to the two-dimensional bionic multistage conical flow divider for laser processing and the application device thereof, the problem that the efficiency of spontaneous continuous separation of existing multiphase immiscible organic liquid drops is low is solved.

Embodiments of the present disclosure relate to a method and system for producing refined hydrocarbons from waste plastic pyrolysis oil. The method and system for producing refined hydrocarbons from waste plastic pyrolysis oil according to the embodiments of the present disclosure may minimize formation of an ammonium salt (NH4Cl) and may prevent an adhesion phenomenon of impurity particles in a reactor in a refining process of waste plastic pyrolysis oil containing impurities including chlorine and nitrogen. In addition, the method and system for producing refined hydrocarbons according to the embodiments of the present disclosure may have excellent refining efficiency and may implement a long-term operation of a process because deactivation of a catalyst used in the process is prevented, and may produce refined hydrocarbons having a low content of impurities and a low content of olefins from waste plastic pyrolysis oil.

The invention relates to the technical field of natural gas separation, in particular to a natural gas pipeline oil mist separation system which comprises a gas inlet end, an oil mist separation mechanism, an exhaust end and an oil dirt discharge mechanism, the gas inlet end comprises a natural gas inlet main pipe and two natural gas inlet branch pipes, and the natural gas inlet branch pipes are connected with a filtering device; the two groups of oil mist separation mechanisms are fixedly mounted on the filtering device and are used for separating and removing oil mist in the natural gas; the exhaust end comprises a natural gas outlet main pipe and two natural gas outlet branch pipes; and the oil mist discharging mechanism is connected with the oil mist separating mechanism and is used for recovering and treating the oil mist. The filtering device comprises a filter, and a filtering assembly composed of a filter element support, a coalescence sintering type filter element and a bearing is arranged in the filtering device. The oil mist separation mechanism comprises a high-pressure steam source, a steam conveying pipe, a steam branch pipe and a blade, and oil mist separation is achieved through steam injection. Oil mist in natural gas can be effectively separated, and the filtering efficiency and the natural gas quality are improved.

The utility model relates to the technical field of coal tar processing equipment, and discloses an oil-water separator for coal tar processing, which comprises a separation tank, the feeding mechanism is arranged at the upper end of the separation tank; the discharging mechanism is arranged at the lower end of the separation tank, the separation tank comprises a tank body, and an oil outlet is formed in one end of the inner side wall of the tank body. According to the oil-water separation tank, the auxiliary water and oil mixture mixing and layering structure is arranged, namely, the spiral flow guide cover is arranged at the top of the tank body and matched with the feeding end, so that a water and oil mixture entering the tank body and a chemical reagent capable of promoting oil-water separation can be discharged after being spirally guided by the spiral flow guide cover, and a stirring mechanism at the bottom of the tank body is matched; according to the oil-water separator, mixing of a chemical reagent and a water-oil mixture can be promoted, rotation of the stirring paddle is stopped after mixing, the water-oil mixture entering the tank body can be rapidly mixed and layered, heavy water in the water-oil mixture can rapidly sink to the bottom, light oil in the water-oil mixture can rapidly float on the water-oil mixture, and therefore rapid oil-water separation is achieved.

The utility model relates to a system for reducing the acid value of hydrolysate in the separation and washing process of dimethyl dichlorosilane hydrolysate. Comprising three stages of coalescers, dimethyl dichlorosilane acidic hydrolysate enters the system from the first stage of coalescer, process water enters the system from the third stage of coalescer, the acidic hydrolysate and diluted hydrochloric acid or process water are mixed in each stage of coalescer, oil-water two-phase separation is completed through multiple times of washing and coalescence, and meanwhile the acid value of the hydrolysate is reduced; each stage of coalescer comprises two static mixers connected in series, a group of prefilters and a large coalescer, the coalescer is Z-shaped, and four stages of filter elements are arranged in each stage of coalescer. Through repeated tests, a modified polyvinylidene fluoride filter element of Pall Company is finally selected, and after continuous three-stage coalescer treatment, the acid value of dimethyldichlorosilane hydrolysate can be reduced to 10 PPM or below.

The invention discloses a Janus super-wettability gradient pore structure cellulose aerogel material for efficient seawater desalination and oil-water separation as well as a preparation method and application of the Janus super-wettability gradient pore structure cellulose aerogel material. According to the aerogel material, a self-assembled gradient pore structure is matched with a high-strength bio-based skeleton formed by chemical crosslinking, an enhanced chemical crosslinking-physical strengthening network structure is formed, and finally solution replacement and normal-pressure drying are performed in absolute ethyl alcohol to obtain the aerogel material. Under the support of a chemical crosslinking effect and a gradient pore physical structure formed by self-assembly of the material, the integrity and mechanical strength of the pore wall of the obtained material are ensured, and meanwhile, in the aerogel preparation and modification process of PVA, PEI and MTMS, the material has excellent upper and lower double-layer super-hydrophobic and super-hydrophilic asymmetric wettability; therefore, the composite material has efficient oil-water emulsion separation performance, lasting super-hydrophilic / underwater super-oleophobic stability, excellent mechanical performance and seawater desalination treatment performance in a high-salinity environment.

According to the automatic continuous treatment equipment for the oily sludge, the sludge is automatically pushed to a conveying cylinder through a pretreatment cylinder, the blocky sludge is crushed by the conveying cylinder and is uniformly conveyed to a treatment box, and magnetic pressing plates are sequentially attracted by electromagnetic blocks to press the sludge downwards, so that dynamic pressure is applied to the sludge, and primary dehydration is realized; meanwhile, demulsification balls are contained in dewatering balls released by the feeding box and penetrate into the sludge under the action of an electromagnetic block, demulsifying agents are released, the oil-water interfacial tension is reduced, an electric heating element is arranged in a spiral transmission rod, water evaporation is promoted through microwave heating, the dewatering balls are matched, and the oily sludge can be effectively dewatered, and magnetic balls move directionally under the action of an electromagnetic field; and the oil-water recycling tank realizes fine separation of oil and water through a filter screen membrane, and a deodorization box of the sludge collection tank synchronously triggers gas circulation for deodorization by utilizing linkage of an elastic air bag and an auxiliary air bag when the dewatering balls are recycled.

Provided are a recirculation system (200) for a material removal machine (102) and a material removal system (100). A material removal system (100) includes a recirculation system (200) in fluid communication with a material removal cabinet (104) housing a material removal machine (102). The recirculation system (200) may have an upper reservoir (300) configured to drain fluid into a lower reservoir (204) before recirculating the fluid. The upper reservoir (300) may have a standpipe (320) configured to allow swarf, debris, and / or other material within the fluid to be entrained prior to flowing over the standpipe (320).

The invention provides a porous bio-based polymer microsphere as well as a preparation method and application thereof. The porous bio-based polymer microsphere provided by the invention comprises a mixture of a bio-based high-molecular polymer P1 and a bio-based block copolymer P2, wherein the bio-based block copolymer P2 is a bio-based block copolymer of which the end-capped group at one end is a hydrophilic group and the end-capped group at the other end is a hydrophobic group. The porous microspheres are prepared by adopting a method of combining condensation phase separation, solvent replacement and solvent volatilization, the obtained microspheres are uniform and stable, the pelletizing rate of the microspheres is nearly high, the yield is high, and subsequent screening is not needed; the process is simple, and the difficulty in operation and control of the process caused by introduction of multiple water phases / oil phases is reduced.

A disk-pack turbine for use, for example, in systems and methods in at least one embodiment for separating fluids including liquids and gases into subcomponents by passing the fluid through a fluid intake chamber into an expansion chamber and then through at least a portion of a waveform pattern present between at least two rotors and / or disks. The rotors and / or disks having waveform patterns on at least one side.

The invention discloses a preparation method of a demulsifier for oil-water separation of full fermentation broth, and relates to the technical field of demulsifier preparation.The preparation method comprises the steps of magnetic nanoparticle preparation, nanoparticle coating and demulsifier preparation.The preparation method has the advantages that salt is dissolved in a three-neck flask, nitrogen is introduced to discharge oxygen in the solution, and the demulsifier is obtained; according to the preparation method, the magnetic nanoparticles are added into the mixture A, so that the generated nanoparticles can be prevented from being oxidized, the mixture A is added in the process of adding the potassium nitrate and the 2-methylimidazole, and the polydopamine in the mixture A has good adhesion and biocompatibility, so that a'bridge '-like connection effect can be achieved between the magnetic nanoparticles and a subsequently generated nanoparticle coated sample; and polyvinylpyrrolidone can be used as a dispersant to prevent agglomeration of generated nano particle coated sample particles, and polar groups on molecular chains of polyvinylpyrrolidone can generate certain interaction with raw materials in a reaction system to optimize the growth process of the nano particle coated sample.

The present disclosure relates to a method for processing of liquefied waste plastics (LWP). The method includes subjecting a liquefied waste plastic-based feedstock to heat treatment (HT processing) in an aqueous solution containing alkali metal hydroxide and / or alkaline earth metal hydroxide to form a heat treated effluent, transferring the heat treated effluent to a separator, subjecting the heat treated effluent to phase separation to isolate at least an oil phase including treated LWP and an aqueous phase including contaminated material, and recycling at least a part of the aqueous phase back to the HT processing.

The invention relates to the field of maleic anhydride process solvent regeneration, and discloses an oil-water mixed emulsion separation device, an oil-water mixed emulsion separation method, a maleic anhydride process solvent regeneration method and a maleic anhydride process solvent regeneration system. The oil-water mixed emulsion separation device is of a horizontal structure and comprises a barrel and a raw material liquid inlet formed in one side of the barrel, and an oil-water pre-separation area, an oil-water coalescence area and a settling separation area which are communicated are sequentially arranged in the barrel from one side of the raw material liquid inlet. The maleic anhydride process solvent regeneration method and system provided by the invention have the advantages of simple process flow, simple device, continuous operation, stable operation, low device energy consumption, high solvent regeneration efficiency, high regeneration quality, low water content in the separated solvent, low solvent content in wastewater and the like. The solvent washing and impurity removal process can be fully carried out, meanwhile, the solvent and wastewater are rapidly separated, the loss of the solvent in the technological process can be reduced, meanwhile, the wastewater treatment difficulty is reduced, and the economic benefits of a refinery plant are greatly improved.

The application relates to a modified separation membrane in the technical field of membrane materials, a preparation method and application thereof. The modified separation membrane comprises a base film and a nanostructure layer on the upper surface of the base film and the membrane hole surface close to one side of the upper surface of the base film; wherein the pore size of the base film is 120-400 mu m; the nanostructure layer is composed of microparticles with a size of 100-1000 nm; the preparation method comprises 3D printing of the separation membrane; and the upper surface of the separation membrane and the membrane hole surface close to one side of the upper surface of the separation membrane are subjected to plasma treatment. The modified separation membrane preparation method combines the 3D printing technology and the membrane separation technology, improves the traditional membrane preparation process, finds a more optimal membrane replacement process, and the modification method is free of chemical agents, has the advantages of being more convenient and fast to operate, high in separation efficiency, low in processing cost, green and pollution-free, and the like, and has important significance in the aspects of membrane separation technology improvement and application of oily wastewater treatment.

The invention provides a segmented coalescence system based on wettability gradient. The system comprises a storage tank, a segmented coalescer and a gravity separation tank, the segmented coalescer is composed of a plurality of layers of coalescence beds, a gravity separation area is clamped between every two layers of coalescence beds, through the wettability gradient design, the interface energy synergistic effect and optimized fluid dynamic characteristics are fully utilized, the separation efficiency reaches up to 98.50%, and the separation effect is good. The mixing design of the super-hydrophilic sand and the super-hydrophobic sand obviously enhances the wetting and coalescence efficiency of oil drops, the particle size gradient design realizes segmented coalescence of the oil drops, the lower layer of small-particle-size sand is demulsified and coalesces small oil drops, the upper layer of large-particle-size sand promotes combination of large oil drops, and the continuous water film and oil film structure effectively avoids the problem of pore channel blockage. And the bed pressure drop is reduced.

The invention belongs to the technical field of oil field gathering and transportation systems, and particularly relates to a combined crude oil dehydration and desalination treatment device which comprises a shell, a pretreatment chamber is arranged at one end in the shell, an ultrasonic demulsification chamber is arranged on one side of the pretreatment chamber, and an electric dehydration settling chamber is arranged on one side of the ultrasonic demulsification chamber. Through the combined design of ultrasonic waves and an electric field, the efficiency and adaptability of crude oil dehydration and desalination are improved, oil-in-water and water-in-oil particles can be effectively opened through the mechanical oscillation effect generated by the ultrasonic generator in the ultrasonic demulsification chamber, free-state oil drops and water drops are formed, and the oil-in-water and water-in-oil particles can be effectively removed. An alternating-current electric field and a direct-current electric field which are respectively formed by the grid plate and the vertical electrode plate can be used for coalescing and settling water drops in oil under the actions of dipole coalescence, oscillation coalescence, electrophoresis coalescence and the like, and due to the synergistic action of the double electric fields, the quality of the dehydrated crude oil is improved, the volume fraction of water in the crude oil is reduced, the power consumption is reduced, and the stability of the electric fields is enhanced.

The present invention provides an integrated device for solid-liquid and oil-water separation of kitchen waste, belonging to the technical field of kitchen waste treatment. The device includes a pretreatment filter screen, a solid-liquid separation filling area, a solid-liquid separation oil filtering area, a solid-liquid separation cleaning area, an oil pump, a shallow pond separation area, a bubble oil removal area, an oil tank and a water tank. The pretreatment filter screen is arranged at the front end of the device, and the solid-liquid separation filling area is arranged behind it. The solid-liquid separation oil filtering area and the solid-liquid separation cleaning area are sequentially arranged behind the solid-liquid separation filling area. The solid-liquid separation oil filtering area is connected to the shallow pond separation area through an oil pump. The bubble oil removal area is arranged behind the shallow pond separation area, and the oil tank and the water tank are connected behind the bubble oil removal area. The device separates and processes the solid-liquid mixture by using the three-way rotation centrifugal method at the source of kitchen waste, and performs multi-stage separation treatment on the oil-water mixture by applying the shallow pond theory, realizing the recycling of kitchen waste and avoiding environmental pollution caused by oil-water leakage during transportation.

The invention relates to the technical field of oil-water separation, in particular to a super-hydrophobic foam copper sheet, a preparation method and application thereof and a foam copper box. The invention provides a super-hydrophobic foam copper sheet. The super-hydrophobic foam copper sheet comprises a foam copper sheet body and a hydrophobic coating located on the surface of the foam copper sheet body. The hydrophobic coating is obtained by calcining preparation raw materials including a fluorinated ethylene-propylene copolymer, polyvinylidene fluoride, polyurethane and hydrophobic silicon dioxide nanoparticles. The super-hydrophobic foam copper sheet can realize continuous and rapid oil absorption, and has excellent oil-water separation efficiency.

The utility model relates to the field of hydrometallurgy, in particular to a nickel sulfate solution deoiling device. Comprising a standing tank connected with a production process outlet end, one end of an oil removal device is connected with the standing tank, the other end of the oil removal device is connected with a resin adsorption column, the resin adsorption column is connected with a regeneration tank, and the regeneration tank is connected with a solution storage tank. According to the oil removal device arranged in the device, oil can be treated step by step according to different existing forms and physical properties of oil in nickel sulfate through internal fiber cotton filtration, resin adsorption and filter screen filtration, and compared with the prior art, the oil removal effect is better; the device is provided with the oil-water separator and the bag filter, so that the oil removal effect can be further improved, and impurities in the nickel sulfate solution can be separated.

The invention provides a preparation method of a Joule heat-assisted super-wetting metal net, a metal net with super-hydrophilic performance and a metal net with super-hydrophobic performance. According to the material, carbon nanotubes are firmly adhered to the surface of a metal net through polydopamine mediation to construct a micro-nano coarse structure, a hydrophobic alkyl compound is grafted through a sulfenyl three-component coupling reaction to reduce surface energy, and a super-hydrophilic / underwater super-oleophobic metal net and a super-hydrophobic metal net are prepared respectively. The Joule heating effect of the material is remarkably enhanced by introducing the carbon nanotubes, so that the temperature of the material can be rapidly increased to 100 DEG C or above within 20 seconds under the ultralow voltage of 2.0 V. The characteristic can be effectively used for in-situ heating viscosity reduction of high-viscosity crude oil, continuous and efficient oil-water separation is achieved in a double-channel separation device, the crude oil flux reaches up to about 3985 L.m <-2 >. H <-1 >, and the separation efficiency exceeds 98.6%. The method is also suitable for stainless steel meshes with micron-sized apertures, and can realize efficient separation of various crude oil emulsions.

The utility model relates to an integrated evaporation device applied to a carbonyl synthesis process, which comprises a catalyst material mixer, a coalescence separator and a combined evaporator, a catalyst material feeding pipe is arranged above the front part of the coalescence separator, a water-phase material discharging pipe is arranged at the middle position below the middle part of the coalescence separator, and a water-phase material discharging pipe is arranged below the water-phase material discharging pipe. A liquid-phase material discharge port is formed in the bottom of the combined evaporator, a water-phase material discharge pipe of the coalescence separator and the liquid-phase material discharge port of the combined evaporator are connected in parallel through a connecting pipeline and then are communicated with the input end of the catalyst material mixer through a playback pump, and through the technical scheme, the activity of a catalyst is effectively improved; the problem of equipment blockage in continuous production is solved, and a catalyst-containing water-phase material generated by the coalescence separator and a catalyst-containing liquid material generated by the combined evaporator are recycled, so that the utilization rate of the catalyst is greatly improved, the loss of the catalyst is effectively reduced, the operation cost is reduced, and production and income are increased.

The utility model provides an oil-water separation device and an oil-water separation system. The oil-water separation device comprises an oil-water separation cavity, wherein the oil-water separation cavity is divided into a first cavity and a second cavity; wherein the first chamber comprises an oil-water inlet and an oil-water outlet of which the cross-sectional area is smaller than that of the oil-water inlet; the second chamber is communicated with the first chamber through the oil-water outlet; the second cavity is provided with a water outlet channel and an oil outlet channel, the oil-water outlet is located between the water outlet channel and the oil outlet channel in the height direction of the oil-water separation cavity, and the oil outlet channel is higher than the water outlet channel; the upper cavity wall of the second cavity is rotationally connected with a rotating plate, a first plate body of the rotating plate is arranged opposite to the oil-water outlet, and a second plate body of the rotating plate is connected with a piston matched with the oil outlet channel; and when an oil-water mixture flowing out of the first chamber from the oil-water outlet impacts the first plate body, the second plate body synchronously performs reciprocating rotation relative to the upper chamber wall of the second chamber, so that the piston closes / opens the oil outlet channel.

The utility model discloses a methanol hydrogen production device which comprises a steam vaporization tank, a cracking reaction tank and a cooler which are connected in sequence, the steam vaporization tank comprises an outer container and an inner container arranged in the middle of the outer container in a sleeved mode, the inner container is used for containing heating media, and a heating pipe is arranged in the inner container; a methanol containing cavity is defined between the inner container and the outer container; and a steam outlet pipe is arranged at the top of the side wall of the outer container. The steam vaporization tank is of a double-layer structure, heat conduction oil is arranged in an inner container and is half-filled, methanol gas is arranged on the upper portion between the inner container and the outer container, liquid is arranged on the lower portion between the inner container and the outer container and is uniformly vaporized into methanol steam, gas on the upper portion is overheated and enters the cracking reaction tank, the cracking reaction tank is provided with a plurality of steel pipes filled with catalysts, and the methanol steam is long in gas path and is uniformly cracked into mixed hydrogen under the action of the catalysts.

The utility model belongs to the technical field of essence processing equipment, and particularly relates to an oil-water separator which comprises a separator shell and a driving motor, the driving motor is mounted on the upper side of the separator shell, and a liquid inlet pipe, an oil outlet valve and a water outlet valve are sequentially mounted on the separator shell. According to the oil-water separator and the rose essence processing equipment, when the capacitive interface sensor does not make contact with a grease layer, the driving motor is started through the controller, the output end of the driving motor drives the screw rod to rotate, the capacitive interface sensor and the flow guide pipe move downwards accordingly, and when the capacitive interface sensor makes contact with the grease layer, the flow guide pipe moves downwards; the output end of the driving motor stops rotating, at the moment, the through groove in the upper side of the flow guide pipe makes contact with the grease layer, the grease layer flows to the hose through the flow guide pipe, the flow guide pipe can move according to the grease layer, and the oil-water separator can conveniently and stably distribute essential oil of the rose liquid mixture.

This disclosure describes methods to separate solids from liquids in a production facility. A process separates components in the process stream by applying non-condensable media to create density differences and then using a mechanical device to separate the solids from the liquids based on the density difference. The process produces the liquids and solids, which may be further processed to create valuable animal feed products.

The invention discloses a cellulose-based cationized carbon nanofiber / cyclodextrin composite demulsifier. The cellulose-based cationized carbon nanofiber / cyclodextrin composite demulsifier is obtained by sequentially carrying out cyclodextrin modification and cationized modification on cellulose-based carbon nanofibers. The preparation method comprises the following steps: firstly, taking biomass cellulose as a raw material, and sequentially carrying out chemical grafting modification, high-pressure homogenization treatment and hydrothermal reaction to prepare cellulose-based carbon nanofibers; then promoting the reaction between the cellulose-based carbon nanofibers and the natural cyclic oligosaccharide cyclodextrin under an ultrasonic condition, and improving the wettability and interfacial activity of the cellulose-based carbon nanofibers; finally, cyclodextrin is modified by utilizing a cationization reagent, so that the surface of cyclodextrin carries a large amount of positive charges, the interfacial activity of the carbon nanofibers is further enhanced, softening of an interfacial film is promoted, the stability of oil drops is reduced, and the demulsification efficiency is effectively improved. The composite demulsifier has the advantages of being small in dosage, low in demulsification temperature, high in demulsification efficiency, easy to degrade and the like, and the related preparation method is simple, environmentally friendly and suitable for application and popularization.