CN111234865A

CN111234865A - Method for treating sump oil

Info

Publication number: CN111234865A
Application number: CN202010048796.3A
Authority: CN
Inventors: 高伟军; 刘建平; 阳光军; 候朝辉; 刘喜斌
Original assignee: Hunan Changke Chengxiang Petrochemical Technology Co ltd
Current assignee: Hunan Changke Chengxiang Petrochemical Technology Co ltd
Priority date: 2020-01-16
Filing date: 2020-01-16
Publication date: 2020-06-05

Abstract

The present disclosure relates to a method of treating contaminated oil, the method comprising: sewage and solid slag are obtained by performing multistage filtration on the dirty oil, purified water is obtained by performing a multi-bed oil-water separation system on the multistage sewage, and the solid slag which can reach the discharge standard is obtained by performing dynamic ultrasonic oil removal and slag formation on the multistage solid slag. The process disclosed by the invention is simple and feasible, can be used for treating the high-water-content and high-solid-content sump oil, has the characteristics of high solid removal and dehydration rate of the sump oil and short recovery period, overcomes the secondary pollution caused by further producing a large amount of sewage by introducing a large amount of water in the sump oil treatment process in the prior art, has low chemical agent dosage, saves the subsequent agent treatment cost, has low operation temperature, and is beneficial to energy conservation.

Description

Method for treating sump oil

Technical Field

The disclosure relates to the field of petrochemical dirty oil treatment, in particular to a method for treating dirty oil.

Background

With the rapid development of economy in China, the processing amount of petroleum which is one of important energy substances is increased year by year, the quantities of petroleum exploitation, processing and storage in China are also increased year by year, and the quantity of unavoidable produced sump oil is also gradually increased. The production of the dirty oil of a refinery is about 0.2 percent of the storage capacity, the crude oil processing amount per year in China currently exceeds 6 hundred million tons, and the amount of the dirty oil generated per year is more than 120 million tons. Therefore, from the aspects of fully and reasonably utilizing resources and protecting environment, an effective method and an effective way for realizing the recycling and standard treatment of the dirty oil generated in the processes of oil exploitation, processing and storage are urgently needed.

The complexity of petroleum sources and production processes causes that the dirty oil contains a large amount of silt, water, acid substance colloid, heavy metal and other impurities, so that the separation and removal of harmful components of the dirty oil are very difficult, and the utilization degree, purification quality and efficiency of the part of resources in the prior art can not meet the production requirements far.

Disclosure of Invention

The invention provides a method for treating sump oil, aiming at improving the utilization rate of sump oil resources in the petrochemical industry and improving the purification quality and efficiency of the sump oil.

To achieve the above object, the present disclosure provides a method for treating contaminated oil, comprising the steps of: s1: enabling the dirty oil raw material to pass through a first filter for first filtration to obtain dirty oil A and solid residues A; s2: preheating the dirty oil A, and then carrying out second filtration through a second filter to obtain dirty oil B, sewage A and solid residues B; s3: performing third filtration on the material containing the dirty oil B through a third filter to obtain dirty oil C, sewage B and solid residues C; s4: performing fourth filtration on the material containing the dirty oil C through a fourth filter to obtain purified oil F, sewage C and solid residues D; s5: mixing the sewage A, the sewage B and the sewage C, and performing fifth filtration through a fifth filter to obtain sewage D and solid slag E; s6: separating the sewage D by a multi-bed oil-water separation system to obtain sump oil D and purified water E; dividing the purified water E into a first stream of purified water E, a second stream of purified water E and a third stream of purified water E; s7: and mixing the solid residue A, the solid residue B, the solid residue C, the solid residue D, the solid residue E and the first stream of purified water E, and then carrying out dynamic ultrasonic oil removal and residue formation to obtain dirty oil E and solid residue F.

Optionally, in step S1, the first filter is one or more of a tube filter, a basket filter, a rotary vibration sieve, a linear sieve, a swing sieve, an ultrasonic vibration sieve, a straight-line sieve and a plate-and-frame filter; the temperature of the first filtration is 40-80 ℃; the weight ratio of the dirty oil A to the solid slag A is (100-1000): 1, wherein the weight of the solid slag a is based on a wet basis.

Optionally, in step S2, the preheating temperature is 50-130 ℃, and the preheating device is one or more of a shell-and-tube heat exchanger, a plate heat exchanger, a jacketed heating kettle and an electric heater;

the second filter is one or more of a horizontal screw machine, a belt filter and a plate and frame filter; the weight ratio of the dirty oil B to the sewage A to the solid slag B is (1-65): (0.10-14): 1, wherein the weight of the solid slag B is calculated on a wet basis.

Optionally, the material containing the dirty oil B in step S3 further contains the third stream of purified water E and a demetallizing agent; wherein the third filter is one or more of a spiral fiber belt, a spiral fiber strip and a spiral fiber sheet; the temperature of the third filtration is 80-150 ℃; the weight ratio of the dirty oil C, the sewage B and the solid slag C is (40-800): (10-100): 1, wherein the weight of the solid slag C is on a wet basis;

the demetallization agent is one or more of phosphoric acid, metaphosphoric acid, phosphate, carboxylic acid, hydroxycarboxylic acid, aminocarboxylic acid, carboxylate, acetic acid, ethylene diamine tetraacetic acid and citric acid; the weight ratio of the dirty oil B to the demetallization agent is (20000-800000): 1.

optionally, in step S4, the material containing dirty oil C further contains dirty oil D and dirty oil E, and the purified oil F is led out as product oil; wherein the weight ratio of the dirty oil D to the dirty oil E is (0.5-5): (5-50); the weight ratio of the purified oil F to the sewage C to the solid slag D is (2-20): (0.5-5): 1, wherein the weight of the solid slag D is on a wet basis; the purified oil F has a water content of less than 0.1 wt% and a slag content of less than 0.05 wt%, the slag content of the purified oil F being on a dry basis; the fourth filter is one or more of a stacked screw machine, a belt filter, a horizontal screw machine, a plate-frame filter, a separator and a centrifuge; the temperature of the fourth filtration is 50-98 ℃.

Optionally, in step S5, the fifth filter is one or more of a separator, a horizontal screw machine, a centrifuge and a belt filter; the temperature of the fifth filtration is 60-130 ℃; the weight ratio of the sewage D to the solid slag E is (0.75-75): 1, wherein the weight of the solid slag E is on a wet basis.

Optionally, step S6 further includes leading out the second stream of purified water E as product water; wherein the weight ratio of the first stream of purified water E, the second stream of purified water E and the third stream of purified water E is (0.1-1): (0.2-2): 1; the weight ratio of the dirty oil D to the purified water E is (0.01-0.1): 1; the oil content in the purified water E is not more than 50 ppm.

Optionally, in step S6, the multi-bed oil-water separation system includes, from top to bottom, a settling separation zone, an adsorption zone, a settling separation buffer zone, and an isolation bed zone; the upper part of the adsorption area is provided with a sewage inlet, the top of the device is provided with a sump oil outlet, and the bottom of the device is provided with a purified water outlet; the settling separation zone comprises a settling separation layer, the adsorption zone comprises an adsorption bed layer, the settling separation buffer zone comprises a settling separation buffer layer, and the isolation interception zone comprises an isolation bed layer; the adsorption zone contains a first type of polymer adsorbent, and the isolation interception zone contains a second type of polymer adsorbent; the first polymer adsorbent is one or more of hydrophobic oleophylic polyurethane sponge, modified polyurethane sponge, perfluorinated silane polyimide, modified fiber balls, hydrophobic oleophylic polypropylene fibers, hydrophobic oleophylic silicon oxide/polytetrafluoroethylene polyurethane, hydrophobic oleophylic carbon nano tubes/silicon oxide polyurethane and hydrophobic oleophylic polydivinylbenzene composite materials, and the weight ratio of the first polymer adsorbent to the sewage D is (0.001-0.2): 1; the second type of polymer adsorbent is one or more of a hydrophilic and oleophobic nano titanium dioxide ceramic membrane, a hydrophilic and oleophobic nano polystyrene net membrane, polycaprolactone, polymethyl methacrylate, polyurethane, an inorganic silicon dioxide fiber membrane and polyhydroxy fatty acid amide, and the weight ratio of the second type of polymer adsorbent to the sewage D is (0.001-0.2): 1.

optionally, step S7 further includes leading out the solid slag F as a product; wherein the material containing the solid slag A, the solid slag B, the solid slag C, the solid slag D, the solid slag E and the first stream of purified water E also contains a dispersant and a cleaning agent; on a wet basis, the ratio of the sum of the weight of the solid slag A, the solid slag B, the solid slag C, the solid slag D and the solid slag E to the weight of the dispersing agent is 1: (0.000001-0.001); on a wet basis, the ratio of the sum of the weight of the solid slag A, the solid slag B, the solid slag C, the solid slag D and the solid slag E to the weight of the cleaning agent is 1: (0.000002-0.002); the weight ratio of the dirty oil E to the solid residue F is (0.2-2): 1, wherein the weight of the solid slag F is calculated on a wet basis; the dispersant is one or more of sulfomethyl tannin, lignosulfonate, maleic anhydride-vinyl acetate copolymer and organic phosphonate; the cleaning agent is one or more of metal soaps, sodium alkyl benzene sulfonate, olefin sodium sulfonate, fatty acid ester sulfonate, alkyl sodium sulfonate, succinate sulfonate, petroleum sulfonate, lignosulfonate and phosphate diester salt.

Optionally, in step S7, the dynamic ultrasonic oil and slag removing system includes a solid slag washing and oil removing machine, where the oil removing machine includes a solid slag slurrying section, a material distribution section, an ultrasonic oil removing section, a reverse washing section, and a filtering and dewatering section; the solid slag slurrying section comprises a solid slag slurrying tank, the solid slag slurrying tank comprises a solid slag inlet, a purified water inlet, a cleaning agent inlet and a dispersing agent inlet, and the tank comprises a stirring device extending below the liquid level; the cloth section comprises one or more of a movable disc belt filter, a rubber belt filter and a rotary drum filter, the cloth section is provided with a solid residue slurrying material inlet, and a slurrying material outlet at the bottom of the solid residue slurrying tank is communicated with the solid residue slurrying material inlet; the ultrasonic oil removing section comprises an ultrasonic vibration device and is provided with a dirty oil outlet; the reverse washing section comprises a heating device, and the heating device is one or more of a tubular heater, a plate heater and an electric heater; the filter dehydration section comprises a vacuumizing device, a plurality of sewage outlets are formed in the bottom of the filter dehydration section and communicated with a sewage inlet of the reverse washing section, and a solid slag outlet is formed in the filter dehydration section.

The technical scheme of this disclosure make full use of the difference of component content in the greasy dirt at different levels, realized purification and recovery to the sump oil through separating step by step, had following beneficial effect:

(1) the method is simple and easy to implement, can treat the dirty oil with high water content and high solid content, has the characteristics of dirty oil solid removal, high dehydration rate and short recovery period, can obtain good economic benefit when being implemented, and can eliminate the pollution of the dirty oil to the environment;

(2) the recovery rate of crude oil can reach more than 99%, the water content of the treated crude oil is lower than 0.1 wt%, the solid content is lower than 0.05 wt% (based on dry basis), and the crude oil has the advantages of low water content, low solid content and good quality and can directly enter a downstream recycling device; the treated sewage contains less than 50ppm of oil and less than 0.01 wt% of solid, has the characteristics of low oil content and low solid content, meets the national direct discharge requirement, and is beneficial to further treatment or direct reuse of the sewage; the treated solid slag has low oil content and water content, and the subsequent solid waste treatment cost is greatly reduced;

(3) the scheme disclosed by the invention can solve the self-production problems of the oil field (such as large storage tank occupation of dirty oil, subsequent treatment of dirty oil, control of crude oil quality and the like), also can thoroughly solve the treatment problem caused by the aged dirty oil in a refinery, and effectively relieves the operation fluctuation of the electric desalting device caused by the recycle of the dirty oil in the refinery;

(4) the treatment process disclosed by the invention is self-circulating, and the defect of secondary pollution caused by a large amount of sewage generated by introducing a large amount of water in the dirty oil treatment process in the prior art is overcome; the chemical agent dosage is low, and only a small amount of chemical agent is used in the processes of demetallization, solid slag and oil removal; the operation temperature of the method is low, and energy conservation is facilitated;

(5) the solid slag can be stably separated and discharged, and a matching device for continuous production can be designed by utilizing the scheme of the solid slag discharge device, so that the defects of intermittent production and manual solid discharge in the conventional method are overcome.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

FIG. 1 is a schematic flow diagram of one embodiment of a treatment method of the present disclosure.

FIG. 2 is a schematic diagram of one embodiment of a multi-bed oil-water separation system in the treatment process of the present disclosure.

FIG. 3 is a schematic diagram of one embodiment of a dynamic ultrasonic oil and slag removal system in the treatment methods of the present disclosure.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

In the present disclosure, unless otherwise stated, the use of directional words such as "up" and "down" generally refers to the up and down of the device in normal use, and specifically refers to the orientation of the drawing in fig. 1. "inner and outer" are meant to refer to the profile of the device itself.

As shown in fig. 1, the present disclosure provides a method of treating dirty oil, the method comprising the steps of: s1: enabling the dirty oil raw material to pass through a first filter for first filtration to obtain dirty oil A and solid residues A; s2: preheating the dirty oil A, and then carrying out second filtration through a second filter to obtain dirty oil B, sewage A and solid residues B; s3: performing third filtration on the material containing the dirty oil B through a third filter to obtain dirty oil C, sewage B and solid residues C; s4: performing fourth filtration on the material containing the dirty oil C through a fourth filter to obtain purified oil F, sewage C and solid residues D; s5: mixing the sewage A, the sewage B and the sewage C, and performing fifth filtration through a fifth filter to obtain sewage D and solid slag E; s6: separating the sewage D by a multi-bed oil-water separation system to obtain sump oil D and purified water E; dividing the purified water E into a first stream of purified water E, a second stream of purified water E and a third stream of purified water E; s7: mixing solid residues A, B, C, D, E and a first stream of purified water E, and then carrying out dynamic ultrasonic oil removal and slag formation to obtain dirty oil E and solid residues F.

The present disclosure is not limited to the source and composition of the dirty oil raw material in the dirty oil tank being treated, and in one embodiment according to the present disclosure, the dirty oil raw material may have a water content of less than 80 wt% and a solids content of less than 20 wt% (solids content on a dry basis). Firstly, removing large solid impurity particles such as branches and stones in the dirty oil to protect a subsequent filtering and separating device, wherein in step S1, the first filter is one or more of a tubular filter, a basket filter, a rotary vibration sieve, a linear sieve, a swing sieve, an ultrasonic vibration sieve, a straight-line sieve and a plate-frame filter, and preferably one or more of the basket filter, the rotary vibration sieve, the linear sieve and the plate-frame filter; the temperature of the first filtration is 40-80 ℃, preferably 60-80 ℃, so that the oil stain is filtered under a certain flowing state; according to different oil stain sources and compositions, the weight ratio of the oil stain A obtained by filtering to the solid slag A is (100) -1000): 1, preferably (300- & ltSP & gt 600-): 1, wherein the weight of the solid slag A is calculated by a wet basis.

In one embodiment according to the present disclosure, the primarily filtered dirty oil is preheated to 50-130 ℃, preferably 80-98 ℃, and the preheating device may be one or more of a shell-and-tube heat exchanger, a plate heat exchanger, a jacketed heating kettle, and an electric heater, preferably one or more of a plate heat exchanger and a jacketed heating kettle, so that the oil stain can have better fluidity to be subjected to second filtration in a subsequent second filter, and dirty oil B, dirty water a, and solid residue B are obtained. Wherein, the water content of the dirty oil B is less than 20 wt%, the solid content is less than 10 wt% (dry basis), the second filter can be one or more of a horizontal screw machine, a belt filter and a plate and frame filter, and preferably can be one or more of a horizontal screw machine and a belt filter; the weight ratio of the dirty oil B, the sewage A and the solid slag B is (1-65): (0.10-14): 1, preferably may be (5-20): (0.2-3): 1, wherein the weight of the solid slag B is calculated on a wet basis.

According to the present disclosure, about 50 wt% of water and 30 wt% of solid residues (solid residue amount is dry basis) can be removed from the twice-filtered dirty oil, and the dirty oil C, the sewage B, and the solid residues C can be obtained by subjecting the dirty oil B obtained in step S2 to the third filtration in the third filter. In one embodiment according to the present disclosure, in step S3, the material containing the dirty oil B further contains a third stream of purified water E and a demetallizing agent; in one embodiment according to the present disclosure, the dirty oil added with the purified water is further filtered in a third filter, so as to further purify the dirty oil and remove heavy metals, wherein the third filter may be one or more of a spiral fiber belt, a spiral fiber strip and a spiral fiber sheet, and preferably may be one or more of a spiral fiber belt and a spiral fiber strip; the temperature of the third filtration is 80-150 ℃, preferably 110-130 ℃; the weight ratio of the dirty oil C, the sewage B and the solid slag C is (40-800): (10-100): 1, preferably may be (80-300): (20-40): 1, wherein the weight of the solid slag C is on a wet basis.

In a specific embodiment according to the present disclosure, the salts and metals in the dirty oil can also be removed, and the demetallizing agent can be added directly to the dirty oil or preferably added to the third purified water E in step S6 of adding the dirty oil B. Wherein, the demetallization agent is one or more of phosphoric acid, metaphosphoric acid, phosphate, carboxylic acid, hydroxycarboxylic acid, aminocarboxylic acid, carboxylate, acetic acid, ethylenediamine tetraacetic acid and citric acid, and preferably one or more of phosphoric acid, phosphate, carboxylic acid and carboxylate; and according to the difference of oil stain sources and compositions and the difference of salts and metal contents in the oil stain, the weight ratio of the oil stain B to the added demetallization agent is (20000-800000): 1, preferably (80000-: 1, the dosage of the chemical agent is low, which is beneficial to environmental protection and reduces the treatment cost of the subsequent chemical agent.

According to the disclosure, the dirty oil C obtained after the third filtration is mixed with the dirty oil D and the dirty oil E for fourth filtration, and the purified oil F is recycled into a tank area as product oil and is used for downstream production, the water content of the processed purified oil is lower than 0.1 wt%, the solid content is lower than 0.05 wt%, the quality is good, and the purified oil can be directly recycled in a device. In one embodiment according to the present disclosure, the ratio by weight of the dirty oil D and the dirty oil E is (0.5-5): (5-50), preferably (1-3): (10-30); the weight ratio of the purified oil F to the sewage C to the solid slag D is (2-20): (0.5-5): 1, preferably may be (5-15): (1-3): 1, wherein the weight of the solid slag D is calculated on a wet basis; the purified oil F has a water content of 0.01 to 0.1 wt%, preferably 0.01 to 0.05 wt%, and a slag content of 0.01 to 0.05 wt%, preferably 0.03 to 0.05 wt%, and the slag content of the purified oil F is calculated on a dry basis, and the purified oil F within the above range can reach the standard of direct recycling of the purified oil, and further purification is not required, thereby saving the investment in processing the contaminated oil. Wherein, the fourth filtering device can be one or more of a stacked screw machine, a belt filter, a horizontal screw machine, a plate-frame filter, a separator and a centrifuge, preferably one or more of a horizontal screw machine, a separator and a centrifuge, wherein the separator is optimal, and the filtering temperature is 60-130 ℃, preferably 80-100 ℃.

According to the disclosure, step S5 mixes the sewage A, the sewage B and the sewage C obtained from the treatment in steps S2-S4, and fifth filtering is carried out by a fifth filter to obtain sewage D and solid slag E, wherein the weight ratio of the sewage D to the solid slag E is (0.75-75): 1, preferably may be (20-35): 1, wherein the weight of the solid slag E is calculated on a wet basis; and the adopted fifth filtering device can be one or more of a separator, a horizontal screw machine, a centrifuge and a belt filter, and preferably can be one or more of a separator and a horizontal screw machine.

According to the present disclosure, step S6 is to separate the sewage D into dirty oil D and purified water E through a multi-bed oil-water separation system shown in fig. 2; dividing the purified water E into a first stream of purified water E, a second stream of purified water E and a third stream of purified water E, leading out the second stream of purified water E as product water, and further processing the product water in a sewage treatment plant as other production water. Wherein the weight ratio of the first stream of purified water E, the second stream of purified water E and the third stream of purified water E is (0.1-1): (0.2-2): 1, preferably may be (0.1-0.5): (0.5-1): 1. the weight ratio of the dirty oil D to the purified water E is (0.01-0.1): 1, preferably may be (0.01-0.05): 1; the oil content in the purified water E does not exceed 50 ppm.

In one embodiment according to the present disclosure, the multi-bed oil-water separation system of step S6 is shown in fig. 2, and includes, from top to bottom, a settling separation zone, an adsorption zone, a settling separation buffer zone, and an isolation bed zone; the upper part of the adsorption area is provided with a sewage inlet, the top of the device is provided with a sump oil outlet, and the bottom of the device is provided with a purified water outlet; the sedimentation separation zone comprises a sedimentation separation layer, the adsorption zone comprises an adsorption bed layer, the sedimentation separation buffer zone comprises a sedimentation separation buffer layer, and the isolation interception zone comprises an isolation bed layer; the adsorption zone contains a first type of polymer adsorbent, and the isolation interception zone contains a second type of polymer adsorbent; the first polymer adsorbent is one or more of hydrophobic oleophylic polyurethane sponge, modified polyurethane sponge, perfluorinated silane polyimide, modified fiber balls, hydrophobic oleophylic polypropylene fibers, hydrophobic oleophylic silicon oxide/polytetrafluoroethylene polyurethane, hydrophobic oleophylic carbon nano tubes/silicon oxide polyurethane and hydrophobic oleophylic polydivinylbenzene composite materials, and the weight ratio of the first polymer adsorbent to the sewage D is (0.001-0.2): 1, preferably may be (0.15-0.2): 1; the second type of polymer adsorbent is one or more of hydrophilic oleophobic nano titanium dioxide ceramic membrane, hydrophilic oleophobic nano polystyrene net membrane, polycaprolactone, polymethyl methacrylate, polyurethane, inorganic silicon dioxide fiber membrane and polyhydroxy fatty amide, and the weight ratio of the second type of polymer adsorbent to the sewage D is (0.001-0.2): 1, preferably may be (0.15-0.2): 1. and (3) allowing the treated sewage D to enter a settling separation zone, allowing the settled water to pass through an adsorption layer filled with an adsorbent, allowing the water phase passing through a bed layer to enter a settling separation buffer zone, allowing the water phase to pass through an isolation interception zone filled with the adsorbent, obtaining purified water E at the bottom of the reactor, and obtaining a separated oil phase D at the top of the reactor.

In a specific embodiment according to the present disclosure, the step S7 further includes drawing out the solid slag F as a product; in order to disperse and purify sump oil aggregates or massive oil sludge in the sump oil after multistage filtration, the material containing solid residues A, B, C, D, E and the first stream of purified water E also contains a dispersant and a cleaning agent; on a wet basis, the weight ratio of the sum of the weight of the solid slag A, the solid slag B, the solid slag C, the solid slag D and the solid slag E to the weight of the dispersing agent is 1: (0.000001-0.001), preferably may be 1: (0.00001-0.0005); the ratio of the sum of the weight of the solid slag A, the solid slag B, the solid slag C, the solid slag D and the solid slag E to the weight of the cleaning agent is 1: (0.000002-0.002), preferably may be 1: (0.00002-0.001); the weight ratio of the dirty oil E to the solid residue F is (0.2-2): 1, preferably may be (0.3-0.9): 1, wherein the weight of the solid slag F is calculated on a wet basis.

In one embodiment according to the present disclosure, the dispersant added in step S7 may be one or more of sulfomethyl tannin, lignosulfonate, maleic anhydride-vinyl acetate copolymer and organic phosphonate, preferably one or more of lignosulfonate and maleic anhydride-vinyl acetate copolymer; the cleaning agent can be one or more of metal soaps, sodium alkyl benzene sulfonates, olefin sodium sulfonates, fatty acid ester sulfonates, alkyl sodium sulfonates, succinate sulfonates, petroleum sulfonates, lignosulfonates and phosphate diester salts, and preferably can be one or more of metal soaps and sodium alkyl benzene sulfonates. The chemical agent disclosed by the invention is low in dosage, and only a small amount of chemical agent is used in the processes of demetallization, solid slag and oil removal, so that the environment is protected, and the treatment cost of subsequent chemical agents is reduced.

In a specific embodiment according to the present disclosure, in step S7, the dynamic ultrasonic oil removal and slagging system shown in fig. 3 includes a solid residue washing and oil removal machine, wherein the oil removal machine includes a solid residue slurrying section, a cloth section, an ultrasonic oil removal section, a reverse washing section and a filtering and dewatering section; the solid slag slurrying section comprises a solid slag slurrying tank, the solid slag slurrying tank comprises a solid slag inlet, a purified water inlet, a cleaning agent inlet and a dispersing agent inlet, and a stirring device extending below the liquid level is arranged in the tank; the material distribution section comprises one or more of a movable disk belt filter, a rubber belt filter and a rotary drum filter, and preferably can be one or more of the movable disk belt filter and the rubber belt filter; the cloth section is provided with a solid residue slurrying material inlet, and a slurrying material outlet at the bottom of the solid residue slurrying tank is communicated with the solid residue slurrying material inlet; the ultrasonic oil removing section comprises an ultrasonic vibration device and is provided with a dirty oil outlet; the reverse washing section comprises a heating device, the heating device is one or more of a tubular heater, a plate heater and an electric heater, and preferably, the heating device can be one or more of a tubular heater and a plate heater; the filter dewatering section comprises a vacuumizing device, a plurality of sewage outlets are arranged at the bottom of the filter dewatering section and communicated with a sewage inlet of the reverse washing section, and a solid slag outlet is formed in the filter dewatering section. Adding solid slag A, solid slag B, solid slag C, solid slag D, solid slag E and a first stream of purified water E into a solid slag slurry tank to obtain uniform slag slurry, sequentially adding a dispersing agent and a cleaning agent, uniformly stirring, passing through a belt filter and an ultrasonic vibration area, carrying out hot water countercurrent washing, carrying out vacuum dehydration to obtain solid slag F, leading the solid slag F out of the world for outsourcing treatment, and greatly reducing the subsequent solid waste treatment cost due to low oil content and low water content of the treated solid slag.

The present disclosure is further illustrated by the following examples, but is not to be construed as being limited thereby.

Examples

The present embodiment provides a method for treating dirty oil, which is implemented by using the above system and apparatus, and the process flow diagram is shown in fig. 1, which includes the following steps.

Feeding dirty oil: the specific gravity is 0.88, the oil content is 130.56kg, the water content is 33.6kg, and the solid content is 11.84 kg.

(1) 176kg of sump oil is taken and passes through a basket filter at the temperature of 50 ℃ to obtain 175.52kg of sump oil A and 0.48kg of solid residue A;

(2) passing 175.52kg of sump oil A through an oil pump, heating the oil at 80 ℃ by using steam heating equipment, and heating the oil by using a horizontal screw machine to obtain 154.5kg of sump oil B, 6.8kg of sewage A and 14.22kg of solid residue B;

(3) adding 30kg of third purified water E into 154.5kg of the sump oil B, adding 0.9g of phosphoric acid demetallization agent into the third purified water E, and passing through a spiral fiber belt at the temperature of 130 ℃ to obtain 151.48kg of sump oil C, 31.87kg of sewage B and 1.15kg of solid residues C;

(4) 151.48kg of dirty oil C, 1.49kg of dirty oil D in the step (6) and 18.31kg of dirty oil E in the step (7) are mixed, the temperature is controlled at 98 ℃, and 129.37kg of purified oil F, 26.71kg of sewage C and 15.20kg of solid residue D are obtained by a separator; transferring the purified oil F to an oil storage tank area for direct use;

(5) mixing 6.8kg of sewage A, 31.87kg of sewage B and 26.71kg of sewage C, controlling the temperature at 80 ℃, and passing the combined sewage through a separator to obtain 63.4kg of sewage D and 1.99kg of solid residue E;

(6) adding 63.4kg of sewage D into a multi-bed oil-water separation system, controlling the temperature at 60 ℃ to obtain 1.49kg of sewage D and 61.9kg of purified water E; transferring 22.93kg of second strand of purified water E to a sewage treatment plant for unified treatment; the first type of polymer adsorbent in the multi-bed oil-water separation system is hydrophobic oleophylic polyurethane sponge, the weight of the first type of polymer adsorbent is 83g, and the second type of polymer adsorbent is a hydrophilic oleophobic nano polystyrene net film, the weight of the second type of polymer adsorbent is 78 g;

(7) adding 33.04kg of solid residues A, 33.04kg of solid residues B, 33.04kg of solid residues C, 33.04kg of solid residues D and 9kg of first purified water E into a solid residue slurry tank to obtain uniform residue slurry, controlling the temperature at 80 ℃, sequentially adding 0.9g of lignosulfonate dispersant and 1.3g of metal soap cleaning agent, uniformly stirring, performing ultrasonic vibration through a belt filter, performing hot water countercurrent washing, and performing vacuum dehydration to obtain 18.31kg of dirty oil E to obtain 23.72kg of solid residues F; and F, treating solid residues by outsourcing.

Comparative example

(1) 176kg of sump oil is taken and passes through a basket filter at the temperature of 50 ℃ to obtain 175.52kg of sump oil A1 and 0.48kg of solid residue A1;

(2) 175.52kg of dirty oil A1 passes through an oil pump, steam heating equipment is utilized, the temperature is controlled to be 80 ℃, and the oil is heated by a horizontal screw machine to obtain 154.5kg of dirty oil B1, 6.8kg of sewage A1 and 14.22kg of solid residue B1;

(3) adding 36kg of fresh water into 154.5g of sump oil B1, adding 1.2g of phosphoric acid demetallization agent into the water, and passing through a fiber membrane contactor at the temperature of 130 ℃ to obtain 150.84kg of sump oil C1, 37.88kg of sewage B1 and 1.79kg of solid residue C1;

(4) 150.84kg of dirty oil C1 is settled and dehydrated for 1 hour, the temperature is controlled at 85 ℃, and 133.25kg of purified oil F1, 5.59kg of dirty water C1 and 11.99kg of solid residue D1 are obtained; wherein the purified oil F1 contains crude oil with a total weight of 127.03 kg;

(5) mixing 6.8kg of sewage A1, 37.88kg of sewage B1 and 5.59kg of sewage C1, treating by an air floatation device, controlling the temperature at 60 ℃ to obtain 48.79kg of purified water D1 and 3.31kg of scum E1;

(6) 6.48kg of solid slag A1, 14.22kg of solid slag B1, 1.79kg of solid slag C1, 11.99kg of solid slag D1 and 3.31kg of scum E1 are combined and analyzed to obtain 8.13kg of dry-based solid slag.

The results of the oil stain treatment in examples and comparative examples are shown in table 1.

TABLE 1 results of oil stain treatment

And (4) analyzing results: as can be seen from the above table 1, in the treatment results of the scheme adopted in the examples, the obtained purified oil, purified water and solid slag have better quality than the comparative example, and have the advantages of high crude oil recovery rate, less chemical reagent consumption, energy conservation, environmental protection and the like.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. A method of treating contaminated oil, the method comprising the steps of:

s1: enabling the dirty oil raw material to pass through a first filter for first filtration to obtain dirty oil A and solid residues A;

s2: preheating the dirty oil A, and then carrying out second filtration through a second filter to obtain dirty oil B, sewage A and solid residues B;

s3: performing third filtration on the material containing the dirty oil B through a third filter to obtain dirty oil C, sewage B and solid residues C;

s4: performing fourth filtration on the material containing the dirty oil C through a fourth filter to obtain purified oil F, sewage C and solid residues D;

s5: mixing the sewage A, the sewage B and the sewage C, and performing fifth filtration through a fifth filter to obtain sewage D and solid slag E;

s6: separating the sewage D by a multi-bed oil-water separation system to obtain sump oil D and purified water E; dividing the purified water E into a first stream of purified water E, a second stream of purified water E and a third stream of purified water E;

s7: and mixing the solid residue A, the solid residue B, the solid residue C, the solid residue D, the solid residue E and the first stream of purified water E, and then carrying out dynamic ultrasonic oil removal and residue formation to obtain dirty oil E and solid residue F.

2. The method of claim 1, wherein in step S1, the first filter is one or more of a tube filter, a basket filter, a rotary vibrating screen, a linear screen, a swinging screen, an ultrasonic vibrating screen, an inline screen, and a plate and frame filter; the temperature of the first filtration is 40-80 ℃; the weight ratio of the dirty oil A to the solid slag A is (100-1000): 1, wherein the weight of the solid slag a is based on a wet basis.

3. The method according to claim 1, wherein in step S2, the preheating temperature is 50-130 ℃, and the preheating device is one or more of a shell-and-tube heat exchanger, a plate heat exchanger, a jacketed heating kettle and an electric heater;

4. The method according to claim 1, wherein in step S3, the material containing the dirty oil B further contains the third stream of purified water E and a demetallizing agent; wherein,

the third filter is one or more of a spiral fiber belt, a spiral fiber strip and a spiral fiber sheet; the temperature of the third filtration is 80-150 ℃; the weight ratio of the dirty oil C, the sewage B and the solid slag C is (40-800): (10-100): 1, wherein the weight of the solid slag C is on a wet basis;

5. the method according to claim 1, wherein in step S4, the material containing dirty oil C further contains dirty oil D and dirty oil E, and the cleaned oil F is taken out as product oil; wherein,

the weight ratio of the dirty oil D to the dirty oil E is (0.5-5): (5-50); the weight ratio of the purified oil F to the sewage C to the solid slag D is (2-20): (0.5-5): 1, wherein the weight of the solid slag D is on a wet basis; the purified oil F has a water content of less than 0.1 wt.% and a residue content of less than 0.05 wt.%, wherein the residue content of the purified oil F is on a dry basis;

the fourth filter is one or more of a stacked screw machine, a belt filter, a horizontal screw machine, a plate and frame filter, a separator and a centrifuge; the temperature of the fourth filtration is 50-98 ℃.

6. The method of claim 1, wherein in step S5, the fifth filter is one or more of a separator, a horizontal screw, a centrifuge and a belt filter; the temperature of the fifth filtration is 60-130 ℃; the weight ratio of the sewage D to the solid slag E is (0.75-75): 1, wherein the weight of the solid slag E is on a wet basis.

7. The method of claim 1, wherein step S6 further comprises, withdrawing the second stream of purified water E as product water; wherein,

the weight ratio of the first strand of purified water E to the second strand of purified water E to the third strand of purified water E is (0.1-1): (0.2-2): 1;

the weight ratio of the dirty oil D to the purified water E is (0.01-0.1): 1; the oil in the purified water E does not exceed 50 ppm.

8. The method as claimed in claim 1, wherein in step S6, the multi-bed oil-water separation system comprises a settling separation zone, an adsorption zone, a settling separation buffer zone and an isolation bed zone from top to bottom; the upper part of the adsorption area is provided with a sewage inlet, the top of the device is provided with a sump oil outlet, and the bottom of the device is provided with a purified water outlet; wherein,

the sedimentation separation zone comprises a sedimentation separation layer, the adsorption zone comprises an adsorption bed layer, the sedimentation separation buffer zone comprises a sedimentation separation buffer layer, and the isolation interception zone comprises an isolation bed layer; the adsorption zone contains a first type of polymer adsorbent, and the isolation interception zone contains a second type of polymer adsorbent;

the first polymer adsorbent is one or more of hydrophobic oleophylic polyurethane sponge, modified polyurethane sponge, perfluorinated silane polyimide, modified fiber balls, hydrophobic oleophylic polypropylene fibers, hydrophobic oleophylic silicon oxide/polytetrafluoroethylene polyurethane, hydrophobic oleophylic carbon nano tubes/silicon oxide polyurethane and hydrophobic oleophylic polydivinylbenzene composite materials, and the weight ratio of the first polymer adsorbent to the sewage D is (0.001-0.2): 1;

the second type of polymer adsorbent is one or more of a hydrophilic and oleophobic nano titanium dioxide ceramic membrane, a hydrophilic and oleophobic nano polystyrene net membrane, polycaprolactone, polymethyl methacrylate, polyurethane, an inorganic silicon dioxide fiber membrane and polyhydroxy fatty acid amide, and the weight ratio of the second type of polymer adsorbent to the sewage D is (0.001-0.2): 1.

9. the method according to claim 1, wherein step S7 further comprises drawing out the solid slag F as a product; wherein,

the material containing the solid slag A, the solid slag B, the solid slag C, the solid slag D, the solid slag E and the first strand of purified water E also contains a dispersant and a cleaning agent; on a wet basis, the ratio of the sum of the weight of the solid slag A, the solid slag B, the solid slag C, the solid slag D and the solid slag E to the weight of the dispersing agent is 1: (0.000001-0.001); on a wet basis, the ratio of the sum of the weight of the solid slag A, the solid slag B, the solid slag C, the solid slag D and the solid slag E to the weight of the cleaning agent is 1: (0.000002-0.002); the weight ratio of the dirty oil E to the solid residue F is (0.2-2): 1, wherein the weight of the solid slag F is calculated on a wet basis;

the dispersant is one or more of sulfomethyl tannin, lignosulfonate, maleic anhydride-vinyl acetate copolymer and organic phosphonate;

the cleaning agent is one or more of metal soaps, sodium alkyl benzene sulfonate, olefin sodium sulfonate, fatty acid ester sulfonate, alkyl sodium sulfonate, succinate sulfonate, petroleum sulfonate, lignosulfonate and phosphate diester salt.

10. The method according to claim 1, wherein in step S7, the dynamic ultrasonic oil and slag removing system comprises a solid slag washing oil remover, wherein the oil remover comprises a solid slag slurrying section, a cloth section, an ultrasonic oil removing section, a reverse washing section and a filtering and dehydrating section; wherein,

the solid slag slurrying section comprises a solid slag slurrying tank, the solid slag slurrying tank comprises a solid slag inlet, a purified water inlet, a cleaning agent inlet and a dispersing agent inlet, and the tank comprises a stirring device extending below the liquid level;

the cloth section comprises one or more of a movable disc belt filter, a rubber belt filter and a rotary drum filter, the cloth section is provided with a solid residue slurrying material inlet, and a slurrying material outlet at the bottom of the solid residue slurrying tank is communicated with the solid residue slurrying material inlet;

the ultrasonic oil removing section comprises an ultrasonic vibration device and is provided with a dirty oil outlet;

the reverse washing section comprises a heating device, and the heating device is one or more of a tubular heater, a plate heater and an electric heater;

the filter dehydration section comprises a vacuumizing device, a plurality of sewage outlets are formed in the bottom of the filter dehydration section and communicated with a sewage inlet of the reverse washing section, and a solid slag outlet is formed in the filter dehydration section.