Chemical hot washing method and apparatus for oily sludge

Abstract

The present application provides a chemical hot washing method and apparatus for oily sludge. The method comprises: crushing, screening, and cleaning oily sludge to obtain a first solid phase product and a first liquid phase product; performing first centrifugal separation treatment on the first liquid phase product to obtain a second solid phase product and a second liquid phase product; preheating and liquefying the second solid phase product to obtain a first mixed product; mixing the first mixed product and a catalytic conditioning agent, to perform a thermal hydrolysis reaction to obtain a second mixed product; performing flash evaporation treatment on the second mixed product, to obtain a third mixed product; mixing the second liquid phase product, the third mixed product, and a demulsifier, and performing demulsification treatment to obtain a fourth mixed product; performing multi-stage separation treatment on the fourth mixed product to obtain a first aqueous phase product, a first oil phase product, and a third solid phase product. Said method solves the technical problem of low treatment efficiency of chemical hot washing methods in the existing technology.

Description

Chemical thermal washing method and apparatus for oily sludge

[0001] This application claims priority to Chinese Patent Application No. 202411954699.5, filed on December 27, 2024, entitled “Chemical Thermal Washing Method and System for Oily Sludge”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to chemical thermal washing technology, and more particularly to a chemical thermal washing method and apparatus for oily sludge. Background Technology

[0003] Oily sludge is a solid waste containing mineral oil generated during oil drilling, storage, transportation, processing, and oily wastewater treatment. Its composition varies depending on its source, but the main components are petroleum, water, and clay minerals. Chemical thermal washing is a widely used technology for treating oily sludge. Its principle is to use a cleaning agent under optimal process parameters to strip the mineral oil from solid materials such as clay minerals, thus achieving oil recovery.

[0004] Chemical thermal washing can effectively recover mineral oil from oil sludge, and has the advantages of mature technology, large processing capacity, and low investment and operating costs. However, with the promotion and application of tertiary oil recovery in oil fields and the improvement of standards, chemical thermal washing has also encountered a series of problems, resulting in a significant decrease in processing energy efficiency, substandard residual solid phase after treatment, and easy generation of secondary pollution.

[0005] To address the aforementioned deficiencies, this application discloses a chemical thermal washing method and apparatus for oily sludge. Summary of the Invention

[0006] This application provides a chemical thermal washing method and apparatus for oily sludge, which solves the technical problem of low treatment efficiency of existing chemical thermal washing methods.

[0007] In a first aspect, embodiments of this application provide a chemical thermal washing method for oily sludge, comprising:

[0008] Step 1: The oily sludge is crushed, screened and washed to obtain the first solid phase product and the first liquid phase product;

[0009] Step 2: Perform a first centrifugal separation process on the first liquid phase product to obtain a second solid phase product and a second liquid phase product;

[0010] Step 3: Preheat and liquefy the second solid product to obtain the first mixed product;

[0011] Step 4: Mix the first mixed product with a catalytic conditioning agent and carry out a hot water hydrolysis reaction to obtain a second mixed product;

[0012] Step 5: Perform flash evaporation on the second mixed product to obtain the third mixed product;

[0013] Step 6: Mix the second liquid product, the third mixed product, and the demulsifier, and perform demulsification treatment to obtain the fourth mixed product;

[0014] Step 7: Perform multi-stage separation processing on the fourth mixed product to obtain the first aqueous phase product, the first oil phase product, and the third solid phase product.

[0015] In one possible implementation, step 5 specifically includes:

[0016] Step 5-1: After the hot water hydrolysis reaction is completed, a first-stage flash evaporation is performed until the pressure difference between the equipment performing step 6 and the first pressure difference between the equipment performing step 5 is less than 0.01 MPa, at which point the first-stage flash evaporation is stopped.

[0017] Step 5-2: When the first pressure difference is greater than 0.01 MPa, perform secondary flash evaporation until the first pressure difference is less than 0.01 MPa or the temperature of the secondary flash evaporation is not greater than 102℃~105℃. Then stop the secondary flash evaporation and use the flash evaporation product as the third mixed product.

[0018] In one possible implementation, step 5-1 further includes:

[0019] The flash vapor generated by the first-stage flash evaporation is used to provide heat for the hot hydrolysis reaction in step 4.

[0020] In one possible embodiment, the catalytic conditioning agent is composed of a dispersant, polyoxyethylene ether, a high-valent electrolyte, and a photosensitizer; the mass ratio is 30%–50%: 10%–20%: 10%–20%: 20%–40%, and the amount added is 0.5%–3% (w);

[0021] The high-valence electrolyte includes one or more of ferric sulfate, ferric chloride, and calcium chloride; the dispersant includes sodium silicate; and the photosensitizer includes titanium dioxide.

[0022] In one possible embodiment, the demulsifier is composed of sodium bicarbonate, a cationic surfactant, a nonionic surfactant, and a carbamide, in a mass ratio of 30%–50%: 10%–20%: 10%–20%: 20%–40%, and the amount added is 0.5%–3% (w).

[0023] The cationic surfactant includes one or more of sodium dodecylbenzenesulfonate and hexadecylammonium chloride; the nonionic surfactant includes polyoxyethylene ether.

[0024] In one possible implementation, step 7 includes:

[0025] The fourth mixed product is subjected to a second centrifugal separation process to obtain a fifth solid product and a third liquid product;

[0026] The third liquid phase product is subjected to three-phase separation to obtain the first aqueous phase product, the first oil phase product, and the third solid phase product.

[0027] In one possible implementation, step 5-2 further includes:

[0028] The flash vapor generated by the secondary flash evaporation is condensed and adsorbed to produce a first gaseous product and a fourth liquid product; the fourth liquid product is then subjected to the three-phase separation process.

[0029] In one possible implementation, in step 4, the reaction temperature is 170℃~230℃ and the reaction time is 20min~60min.

[0030] In one possible implementation, in step 6, the stirring speed is 100-200 r / min and the reaction time is 20-30 min.

[0031] In one possible implementation, step 1 specifically includes:

[0032] The oil sludge in the raw material storage tank is crushed by a crusher and subjected to initial rinsing to obtain the fourth solid phase product.

[0033] The fourth solid product is separated by multi-stage vibrating sieve separation and then subjected to secondary rinsing to obtain the first solid product. The waste liquid obtained from the first and second rinsing is used as the first liquid product.

[0034] Secondly, embodiments of this application provide a chemical thermal washing apparatus for oily sludge, used to implement the above method, including a crushing and vibrating screen device, a first centrifugal separation device, a preheating liquefaction device, a reaction device, a flash demulsifier, and a multi-stage separation device; wherein

[0035] The crushing and vibrating screen device is used to crush, screen and clean oily sludge to obtain a first solid product and a first liquid product.

[0036] The first centrifugal separation device is used to perform a first centrifugal separation process on the first liquid phase product to obtain a second solid phase product and a second liquid phase product.

[0037] The preheating liquefaction device is used to preheat and liquefy the second solid product to obtain the first mixed product.

[0038] The reaction apparatus is used to mix the first mixed product with a catalytic conditioning agent and carry out a hot water hydrolysis reaction to obtain a second mixed product;

[0039] It is also used to flash evaporate the second mixture to obtain a third mixture;

[0040] A flash demulsifier is used to mix the second liquid phase product, the third mixed product and a demulsifier, and perform demulsification treatment to obtain a fourth mixed product.

[0041] The multi-stage separation device performs multi-stage separation processing on the fourth mixed product to obtain a first aqueous phase product, a first oil phase product, and a third solid phase product.

[0042] In one possible implementation, the reaction apparatus is further used for:

[0043] After the hot water hydrolysis reaction is completed, a first-stage flash evaporation is performed until the pressure difference between the equipment performing step 6 and the first pressure difference between the equipment performing step 5 is less than 0.01 MPa. Then, the first-stage flash evaporation is stopped, and the flash vapor generated by the first-stage flash evaporation is transported to the hot liquefaction device.

[0044] When the first pressure difference is greater than 0.01 MPa, a second-stage flash evaporation is performed until the first pressure difference is less than 0.01 MPa or the temperature of the second-stage flash evaporation is not greater than 102°C to 105°C. Then, the second-stage flash evaporation is stopped, and the flash evaporation product is used as the third mixed product. The flash vapor generated by the second-stage flash evaporation is transported to the gas processing device.

[0045] The apparatus further includes a gas processing device; the gas processing device is used for:

[0046] The flash vapor generated by the secondary flash evaporation is subjected to condensation and adsorption treatment to obtain a first gaseous product and a fourth liquid product.

[0047] In one possible implementation, the multi-stage separation device includes a second centrifugal separation device, an oil-water storage tank, and a three-phase separation device, wherein:

[0048] The second centrifugal separation device is used to perform a second centrifugal separation process on the first mixed product to obtain a fifth solid phase product and a third liquid phase product;

[0049] The third liquid product is transported to the three-phase separation device through the oil-water storage tank. The first inlet of the oil-water storage tank is connected to the outlet of the second centrifugal separation device, and the outlet of the second centrifugal separation device is connected to the inlet of the three-phase separation device.

[0050] The three-phase separation device is used to perform three-phase separation treatment on the fifth liquid phase product to obtain the first aqueous phase product, the first oil phase product, and the third solid phase product.

[0051] In one possible implementation, the gas treatment device includes a condenser, an activated carbon adsorption unit, and an induced draft fan; wherein

[0052] The condensation device is used to condense the flash vapor generated by the secondary flash evaporation to produce a fourth liquid phase product and a second gas phase product; the liquid phase outlet of the condensation device is connected to the second liquid inlet of the oil-water storage tank.

[0053] The activated carbon adsorption device is used to adsorb the second gaseous product with activated carbon to obtain the first gaseous product, and the first gaseous product is discharged through the induced draft fan.

[0054] The embodiments of this application provide a chemical thermal washing method and apparatus for oily sludge, which solves the technical problem of low treatment efficiency of existing chemical thermal washing methods. Attached Figure Description

[0055] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0056] Figure 1 shows a chemical thermal washing device for oily sludge provided in an embodiment of this application.

[0057] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments.

[0058] Explanation of reference numerals in the attached drawings: 1-Raw material storage tank; 2-Crusher; 3-Three-stage vibrating screen; 4-First centrifugal separation device; 5-Preheating liquefaction device; 6-Reaction device; 7-Flash demulsification tank; 8-Second centrifugal separation device; 9-Oil-water storage tank; 10-Three-phase separation device; 11-Steam generator; 12-Cooling tower; 13-Condensation device; 14-Activated carbon adsorption device; 15-Exhaust fan; 16-Oil storage tank; 17-Water storage tank; 21-Oil-containing sludge; 22-Tap water; 23-Catalytic conditioner; 24-Demulsifier; 25-Waste residue; 26-Waste gas; 27-Wastewater; 28-Recovered oil. Detailed Implementation

[0059] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims, and not all embodiments. The embodiments in this application were obtained by those skilled in the art without inventive effort.

[0060] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0061] In the description of this application, it should be understood that the terms used, including "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", and "outer", are used to indicate orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the equipment or method of this application and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0062] In the specification, claims, and accompanying drawings of this application, the terms "first," "second," and "third" are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such uses of these terms can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein.

[0063] Furthermore, the terms “comprising” and “having”, and any variations thereof, in the description are intended to cover non-exclusive inclusion; for example, a process, method, apparatus, product, or maintenance tool that includes a series of steps or units is not limited to those steps or units that are explicitly listed, but also includes other steps or units that are not explicitly listed or that are inherent to such process, method, product, or maintenance tool.

[0064] It should be noted that "at the time of..." in the embodiments of this application can be either at the instant when a certain situation occurs, or within a period of time after the occurrence of a certain situation. The embodiments of this application do not specifically limit this.

[0065] In existing technologies, the chemical thermal washing method for oily sludge generated during oil extraction typically involves adding a washing fluid and circulating it under heating and stirring to promote the separation of oil sludge before treating the wastewater. Chemical thermal washing can effectively recover mineral oil from oily sludge and has advantages such as mature technology, large processing capacity, and low investment and operating costs. However, with the widespread application of tertiary oil recovery in oil fields and the increasing standards, the wastewater often fails to meet discharge standards and requires further treatment according to environmental protection requirements to avoid environmental pollution, significantly reducing its treatment efficiency.

[0066] Among them, the energy efficiency of chemical thermal washing for fine oily sludge is significantly reduced. Fine oily sludge refers to oily sludge with a median particle size generally ≤100μm, including bottom sludge from crude oil storage tanks, scum and bottom sludge from oily wastewater treatment plants, and oily mud. Its inorganic solid phase mainly consists of clay, chemical agents, and inorganic salts, while its organic matter includes mineral oil with high contents of colloids and asphaltenes, as well as macromolecular organic surfactants and polymers added during oil extraction, gathering and transportation, and wastewater treatment. It is a highly stable multiphase emulsion system. Direct chemical thermal washing is inefficient and causes significant secondary pollution, mainly due to low treatment load, large wastewater volume with high pollutant content, high water and mechanical impurity content in the recovered oil, low solid phase recovery rate, and high oil content.

[0067] This application provides a chemical thermal washing method and apparatus for oily sludge, which can improve the energy efficiency of chemical thermal washing and solve the technical problem of low processing efficiency of existing chemical thermal washing methods.

[0068] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0069] The first aspect of this application provides a chemical thermal washing method for oily sludge, the method specifically including:

[0070] Step 1: The oily sludge is crushed, screened, and washed to obtain the first solid phase product and the first liquid phase product;

[0071] The following is a detailed explanation of step 1:

[0072] Step 1-1: The oily sludge is crushed and then subjected to initial rinsing to obtain the fourth solid product.

[0073] Specifically, oily sludge refers to the oily sludge found in raw material storage ponds during the processes of oil drilling, storage, transportation, processing, and oily wastewater treatment.

[0074] Specifically, the oil sludge in the raw material storage pool can be transferred to a crusher for crushing using a gantry crane grab bucket.

[0075] Specifically, the crushed particle size is 50mm to 100mm.

[0076] Steps 1-2: After the fourth solid product is separated by multi-stage vibrating sieve, it is washed twice to obtain the first solid product; the waste liquid obtained from the first and second washing is used as the first liquid product.

[0077] Specifically, a three-stage vibrating screen can be used for separation, with the first-stage screen having a mesh size of 20mm to 50mm, the second-stage screen having a mesh size of 5mm to 20mm, and the third-stage screen having a mesh size of 2mm to 5mm.

[0078] Specifically, the first liquid phase product is a sludge-like mixed liquid produced after the initial and second rinsing.

[0079] Specifically, water can be stored in a storage tank for use in both initial and secondary rinsing.

[0080] Furthermore, the first solid product is discharged as waste residue.

[0081] Step 2: Perform a first centrifugal separation process on the first liquid phase product to obtain a second solid phase product and a second liquid phase product;

[0082] Specifically, a horizontal spiral centrifuge, a vertical centrifuge, or a disc centrifuge can be used for the first centrifugal separation process to achieve solid-liquid separation.

[0083] Furthermore, a horizontal spiral centrifuge can be used, with a centrifugal speed of 2500–3100 r / min.

[0084] Step 3: Preheat and liquefy the second solid product to obtain the first mixed product;

[0085] Specifically, the temperature for preheating liquefaction is 90℃~95℃. After reaching this temperature and the reaction equipment in step 3 is idle, step 3 can be further executed.

[0086] Specifically, the preheating liquefaction process increases the fluidity of the liquid on the surface of the second solid product, thereby improving the reaction effect in step 3; and the preheating process shortens the preheating time in step 4, thus reducing the overall processing time of step 4.

[0087] Step 4: Mix the first mixed product with a catalytic conditioning agent and carry out a hot water hydrolysis reaction to obtain the second mixed product;

[0088] Specifically, the reaction temperature is 170℃~230℃, and the reaction time is 20min~60min.

[0089] Specifically, the above reaction temperature is achieved by introducing steam, which can promote heating, stirring, and participation in the reaction.

[0090] Furthermore, the reaction time can be selected as 30 minutes or 50 minutes.

[0091] Specifically, the hot hydrolysis reaction can be carried out in a reactor. Since the reactor needs to control the pressure and temperature, the catalytic conditioner is generally not added to the reactor. Therefore, the catalytic conditioner is added in step 3, or added to the pipeline at the inlet of the reactor.

[0092] Specifically, the catalytic conditioning agent is composed of a dispersant, polyoxyethylene ether, high-valent electrolyte, and photosensitizer; in the catalytic conditioning agent, the mass ratio of dispersant, polyoxyethylene ether, high-valent electrolyte, and photosensitizer is 30%–50%: 10%–20%: 10%–20%: 20%–40%, and the amount added is 0.5%–3% (w).

[0093] Specifically, the high-valent electrolyte is one or more of ferric sulfate, ferric chloride, and calcium chloride; the dispersant is sodium silicate; and the photosensitizer is titanium dioxide.

[0094] On the one hand, the first mixed product is a paste, with the molecular weights of the gums and asphaltenes ranging from several thousand to several million, exhibiting stronger hydrophilicity. Water ionizes into hydrogen ions at high temperatures, which, under the action of a catalytic conditioner, attack the weak points of the large organic molecules, promoting chain scission and molecular reduction. This weakens the hydrophilicity, causing the decomposition into lipophilic organic compounds, such as straight-chain alkanes. Further processes such as gum breaking, de-temperature treatment, and dehydration not only improve treatment efficiency but also ensure safety and economic efficiency, while also benefiting environmental protection.

[0095] On the other hand, the hydrolysis reaction allows the inorganic salts in the sludge to dissolve. As the inorganic salts dissolve, they transfer from the solid phase of the sludge to the liquid phase, making the remaining solid phase purer and easier to handle or dispose of. The total volume of the sludge also decreases, which not only reduces the amount of material that needs to be handled or disposed of, thus lowering associated costs, but also facilitates a more thorough removal of oil and other contaminants.

[0096] Step 5: Flash evaporate the second mixture to obtain the third mixture.

[0097] Specifically, steps 4 and 5 are carried out in the same reaction apparatus. Step 4 involves a hot hydrolysis reaction at high temperature, followed by flash evaporation via a pressure relief valve.

[0098] Specifically, flash evaporation refers to the phenomenon where, when a liquid under high pressure is rapidly depressurized to a low-pressure environment, some of the liquid evaporates into gas because the temperature is higher than the boiling point under the new pressure conditions. This process usually occurs when a liquid suddenly enters a low-pressure region from a high-pressure area. Step 5 is described in detail below, and includes the following:

[0099] Step 5-1: After the hot water hydrolysis reaction is completed, perform first-stage flash evaporation until the pressure difference between the equipment where step 6 is performed and the first pressure difference between the equipment where step 5 is performed is less than 0.01 MPa, then stop the first-stage flash evaporation.

[0100] Furthermore, this step also includes:

[0101] The flash vapor generated by the first-stage flash evaporation is used to provide heat for the hydrolysis reaction in step 4.

[0102] Furthermore, steps 3 and 4 can be heated by a steam generator at a temperature of 150°C to 250°C.

[0103] Specifically, first-stage flash evaporation can be achieved by relieving pressure through the first pressure relief valve. The outlet of the first pressure relief valve is connected to the reaction equipment in step 3, which can improve energy utilization.

[0104] Specifically, when the temperature of the preheating liquefaction process in step 3 is greater than 105°C, the steam generator is shut off from the heating channel in step 3. If the flash steam provided by the first pressure relief valve can be used to achieve the temperature of the preheating liquefaction process, then the steam generator is shut off to improve energy utilization.

[0105] Step 5-2: When the first pressure difference is greater than 0.01 MPa, perform secondary flash evaporation until the first pressure difference is less than 0.01 MPa or the temperature of the secondary flash evaporation is not greater than 102℃~105℃. Then stop the secondary flash evaporation and use the flash evaporation product as the third mixed product.

[0106] Furthermore, step 5-2 also includes:

[0107] The flash vapor generated by the secondary flash evaporation is condensed and adsorbed to produce a first gaseous product and a fourth liquid product; the fourth liquid product is then subjected to three-phase separation in step 7.

[0108] Specifically, the flash vapor generated by the secondary flash evaporation of the condensing device is condensed to produce a fourth liquid phase product and a second gaseous phase product; the liquid phase outlet of the condensing device is connected to a three-phase separation device, and the second gaseous phase product is adsorbed by activated carbon to obtain a first gaseous phase product, which can be directly discharged.

[0109] Specifically, two-stage flash evaporation can be achieved by relieving pressure through the second pressure relief valve, and the outlet of the first pressure relief valve is connected to the condenser.

[0110] Furthermore, the liquid phase outlet of the condensation unit can be piped to an oil-water storage tank, and the outlet of the oil-water storage tank is connected to the inlet of the three-phase separation unit.

[0111] Step 6: Mix the second liquid product, the third mixed product, and the demulsifier, and perform demulsification treatment to obtain the fourth mixed product;

[0112] Specifically, the demulsifier is composed of sodium bicarbonate, cationic surfactant, nonionic surfactant and carbamide, with a mass ratio of 30% to 50%: 10% to 20%: 10% to 20%: 20% to 40%, and the amount added is 0.5% to 3% (w).

[0113] Specifically, the cationic surfactant is one or more of sodium dodecylbenzenesulfonate and hexadecylammonium chloride;

[0114] Specifically, the nonionic surfactant is polyoxyethylene ether AEO / SP169;

[0115] Specifically, the above demulsification reaction is carried out in a flash demulsifier, with a stirring speed of 100-200 r / min and a reaction time of 20-30 min.

[0116] Specifically, when the third mixed product enters the flash demulsifier from the reactor, it changes from a high-pressure environment to a low-pressure environment, generating a large amount of steam. With the help of the demulsifier, the volume of the third mixed product expands rapidly, destroying the emulsified structure of the third mixed product and releasing oil and gas; cracking residual organic matter and the encapsulated network and flocculent structures, effectively reducing the interfacial tension of the liquid phase product, which helps the hydrolysis and separation of the liquid phase mixed product.

[0117] Step 7: Perform multi-stage separation on the fourth mixed product to obtain the first aqueous phase product, the first oil phase product, and the third solid phase product.

[0118] Step 7-1: Perform a second centrifugal separation process on the fourth mixed product to obtain the fifth solid phase product and the third liquid phase product;

[0119] Specifically, a horizontal spiral centrifuge, a vertical centrifuge, or a disc centrifuge can be used for a second centrifugal separation process to achieve solid-liquid separation.

[0120] Specifically, the second centrifugal separation process uses a horizontal spiral centrifuge with a rotation speed set to 2000–4000 r / min.

[0121] Step 7-2: Perform three-phase separation on the third liquid phase product to obtain the first aqueous phase product, the first oil phase product, and the third solid phase product.

[0122] Specifically, the three-phase separation process uses a disc centrifuge with a rotation speed of 5000–8000 r / min.

[0123] Furthermore, the third liquid phase product can be transported to an oil-water storage tank; the oil-water storage tank includes the fourth liquid phase product and the third liquid phase product, and the outlet of the oil-water storage tank is connected to the inlet of the three-phase separation processor.

[0124] Furthermore, the first aqueous phase product generated can be transported to a water tank for reuse via pipeline, or it can be treated and discharged externally, further realizing water conservation, energy conservation, and secondary utilization of the demulsifier.

[0125] Furthermore, the first oil phase product generated can be stored in an oil storage tank and recycled.

[0126] Furthermore, the third solid product generated from the second centrifugal separation process is mixed with the third solid product and discharged as waste residue.

[0127] This application provides a chemical thermal washing method for oily sludge, comprising: crushing, screening, and washing the oily sludge to obtain a first solid phase product and a first liquid phase product; performing a first centrifugal separation on the first liquid phase product to obtain a second solid phase product and a second liquid phase product; preheating and liquefying the second solid phase product to obtain a first mixed product; mixing the second liquid phase product and the first mixed product with a catalytic conditioning agent and performing a hot hydrolysis reaction to obtain a second mixed product; flash evaporating the second mixed product to obtain a third mixed product; mixing the third mixed product with a demulsifier and performing a demulsification treatment to obtain a fourth mixed product; and performing multi-stage separation on the fourth mixed product to obtain a first aqueous phase product, a first oil phase product, and a third solid phase product. This method has the following beneficial effects:

[0128] This application preheats and liquefies solid substances by using a catalytic conditioning agent, which can be used to dissolve and liquefy oil on the surface of solid objects, reduce the contamination of solid products, increase the fluidity of the liquid on the surface of the second solid product, and preheat the hot water hydrolysis reaction in advance, thus shortening the processing time of the hot water hydrolysis reaction.

[0129] This application employs a catalytic conditioning agent in conjunction with a hot water hydrolysis reaction. On one hand, water ionizes into hydrogen ions at high temperatures. Under the action of the catalytic conditioning agent, these ions attack the weak points of large organic molecules, promoting chain scission and molecular reduction, thus weakening hydrophilicity and decomposing into lipophilic organic compounds. This further achieves debinding, dehydration, and decontamination, improving the efficiency of the method. On the other hand, the hot water hydrolysis reaction dissolves inorganic salts. As these salts dissolve, they transfer from the solid phase of the sludge to the liquid phase, making the remaining solid phase purer and easier to handle or dispose of. The total volume of the sludge also decreases, reducing the amount of material requiring treatment or disposal and lowering related costs. This also contributes to a more thorough removal of oil and other contaminants.

[0130] Specifically, when the third mixed product enters the flash demulsifier from the reactor, it changes from a high-pressure environment to a low-pressure environment, generating a large amount of steam. With the help of the demulsifier, the volume of the third mixed product expands rapidly, destroying the emulsified structure of the third mixed product and releasing oil and gas; cracking residual organic matter and the encapsulated network and flocculent structures, effectively reducing the interfacial tension of the liquid phase product, which helps the hydrolysis and separation of the liquid phase mixed product.

[0131] Compared with existing chemical thermal washing methods, this application significantly improves the thermal washing efficiency of oily sludge, increasing the treatment capacity from 46.2-64.2% of the initial design capacity to 96.4-102.8%.

[0132] After treatment using the method described in this application, the oil content of the solid waste is ≤2%, which meets the petroleum industry treatment standards.

[0133] After treatment by the method described in this application, the chemical oxygen demand (COD) of the liquid waste is ≤10000 mg / L and the suspended solids (SS) is ≤1000 mg / L. After flocculation treatment, the COD is ≤500 mg / L and the suspended solids (SS) is ≤100 mg / L, which meets the influent water quality requirements of wastewater treatment plants. The recovered oil has a water content of ≤2.0% and mechanical impurities of ≤1.0%, which meets the collection and transportation standards.

[0134] The method described in this application improves the recovery rate of mineral oil, and the quality of the recovered oil meets the standards for crude oil gathering and transportation.

[0135] Example 1

[0136] This application embodiment describes the treatment of heavy oil sludge from an oilfield using the above-mentioned method, the method comprising:

[0137] Step 1: The oily sludge is crushed, screened and washed to obtain the first solid phase product and the first liquid phase product;

[0138] Specifically, the fourth solid product can be obtained by using a gantry crane grab bucket to move the oil sludge in the raw material storage pool into a crusher for crushing treatment, with a crushing particle size of 100mm.

[0139] The fourth solid product was separated by a three-vibration sieve and then washed twice to obtain the first solid product; the waste liquid obtained from the first and second washings was used as the first liquid product.

[0140] The screen openings of the first-stage screen are 50mm, the second-stage screens are 20mm, and the third-stage screens are 5mm.

[0141] Step 2: Perform a first centrifugal separation process on the first liquid phase product to obtain a second solid phase product and a second liquid phase product;

[0142] Specifically, a horizontal spiral centrifuge can be used, with the centrifugal speed set at 3000 r / min, and the solid phase moisture content after separation ≤80%.

[0143] Step 3: Preheat and liquefy the second solid product to obtain the first mixed product.

[0144] Specifically, the temperature for preheating liquefaction is 90℃.

[0145] Step 4: The first mixed product is mixed with a catalytic conditioner and subjected to a hot water hydrolysis reaction to obtain the second mixed product.

[0146] Specifically, the reaction temperature is 230℃ and the reaction time is 30 minutes.

[0147] Specifically, in the catalytic conditioning agent, the mass ratio of dispersant, polyoxyethylene ether, high-valent electrolyte and photosensitizer is 30%:10%:20%:40%, and the amount added is 0.5% (w).

[0148] The high-valence electrolyte is ferric sulfate; the dispersant is sodium silicate; and the photosensitizer is titanium dioxide.

[0149] Specifically, steps 3 and 4 involve supplying steam via a steam boiler at a temperature of 250°C.

[0150] Step 5: Flash evaporate the second mixture to obtain the third mixture.

[0151] Specifically, after the hot hydrolysis reaction is completed, a first-stage flash evaporation is performed until the pressure difference between the equipment performing step 6 and the first pressure difference between the equipment performing step 5 is less than 0.01 MPa, at which point the first-stage flash evaporation is stopped.

[0152] When the first pressure difference is greater than 0.01 MPa, a second-stage flash evaporation is performed until the first pressure difference is less than 0.01 MPa or the temperature of the second-stage flash evaporation is not greater than 102℃~105℃. Then, the second-stage flash evaporation is stopped, and the flash evaporation product is used as the third mixed product.

[0153] Step 6: Mix the second liquid product, the third mixed product, and the demulsifier, and perform demulsification treatment to obtain the fourth mixed product.

[0154] Specifically, the demulsifier is composed of sodium bicarbonate, cationic surfactant, nonionic surfactant and carbamide, with a mass ratio of 50%:10%:20%:20% and an addition amount of 3% (w).

[0155] Specifically, the cationic surfactant is sodium dodecylbenzenesulfonate.

[0156] Specifically, the nonionic surfactant is polyoxyethylene ether AEO / SP169.

[0157] Specifically, the above demulsification reaction is carried out in a flash demulsifier with a stirring speed of 200 r / min and a reaction time of 30 min.

[0158] Step 7: Perform multi-stage separation on the fourth mixed product to obtain the first aqueous phase product, the first oil phase product, and the third solid phase product.

[0159] Specifically, the fourth mixed product is subjected to a second centrifugal separation process to obtain a fifth solid phase product and a third liquid phase product; the third liquid phase product is subjected to a three-phase separation process to obtain a first aqueous phase product, a first oil phase product and a third solid phase product.

[0160] Specifically, the second centrifugal separation process uses a horizontal spiral centrifuge with a speed of 2000 r / min, and the three-phase separation process uses a disc centrifuge with a speed of 5000 r / min.

[0161] The original oily sludge had a water content of 38.94% and an oil content of 17.52% (as received). The original equipment had a residual solid phase oil content of 8.82% (dry basis) after treatment, and its processing capacity was only 46.2% of the design capacity. After treatment using the method described in this application, the residual solid phase oil content was 1.83% (dry basis), the oil recovery rate was 95.2%, the recovered oil had a water content of 1.81%, the mechanical impurity content was 0.47%, the treatment cost decreased by 17.32%, and the processing capacity reached 96.4% of the design capacity.

[0162] Example 2

[0163] The sludge containing polymeric sludge from a certain oilfield was treated using the method described in this application. This method is basically the same as that in Example 1, except that:

[0164] In step 1, the crushed particle size is set to 50mm. The sieve opening of the primary screen is 20mm, the sieve opening of the secondary screen is 10mm, and the sieve opening of the tertiary screen is 5mm.

[0165] In step 2, the rotational speed of the horizontal screw centrifuge is set to 2500 r / min.

[0166] In step 3, the temperature for preheating liquefaction is 100℃.

[0167] In step 4, the reaction temperature is 150℃ and the reaction time is 50 min.

[0168] In the catalytic conditioning agent, the mass ratio of dispersant, polyoxyethylene ether, high-valent electrolyte and photosensitizer is 50%:10%:10%:30%, and the amount added is 0.5% (w).

[0169] The high-valent electrolyte is ferric chloride.

[0170] In step 6, the demulsifier is composed of sodium bicarbonate, cationic surfactant, nonionic surfactant and carbamide, with a mass ratio of 30%:20%:10%:40% and an addition amount of 0.5% (w).

[0171] Specifically, the cationic surfactant is hexadecyl ammonium chloride.

[0172] The demulsification reaction was carried out at a stirring speed of 200 r / min for 20 min.

[0173] In step 7, the horizontal spiral centrifuge is set to a speed of 4000 r / min.

[0174] Specifically, the three-phase separation process uses a disc centrifuge with a rotation speed of 8000 r / min.

[0175] The original oily sludge had a water content of 77.43% and an oil content of 9.84% (as received). The original unit's residual solid phase after treatment had an oil content of 5.37% (dry basis), and its processing capacity was only 52.6% of the design capacity. After treatment using the method described in this application, the residual solid phase had an oil content of 1.42% (dry basis), the recovered oil had a water content of 0.82%, and the mechanical impurity content was 0.35%, achieving a processing capacity of 101.1% of the design capacity.

[0176] Example 3

[0177] The method described in this application is used to treat oil sludge from an oil refinery. This method is basically the same as that in Example 1, except that:

[0178] In step 1, the crushed particle size is set to 80mm. The sieve opening of the primary screen is 40mm, the sieve opening of the secondary screen is 20mm, and the sieve opening of the tertiary screen is 5mm.

[0179] In step 2, the rotational speed of the horizontal screw centrifuge is set to 3100 r / min.

[0180] In step 3, the temperature for preheating liquefaction is 90℃.

[0181] In step 4, the reaction temperature is 170℃ and the reaction time is 60 min.

[0182] In the catalytic conditioning agent, the mass ratio of dispersant, polyoxyethylene ether, high-valent electrolyte and photosensitizer is 40%:20%:20%:20%, and the amount added is 2% (w).

[0183] The high-valent electrolyte is calcium chloride.

[0184] In step 6, the demulsifier is composed of sodium bicarbonate, cationic surfactant, nonionic surfactant and carbamide, with a mass ratio of 40%:20%:20%:20% and an addition amount of 2% (w).

[0185] The demulsification reaction was carried out at a stirring speed of 100 r / min for 30 min.

[0186] In step 7, the horizontal spiral centrifuge is set to a speed of 3000 r / min, and the three-phase separation process uses a disc centrifuge with a speed of 7000 r / min.

[0187] After the original equipment was used for treatment, the oil recovery rate was 91.7% after using this method. The oil content in the remaining solid phase was 0.98%, the water content in the recovered oil was 0.73%, and the mechanical impurity content was 0.24%.

[0188] The original oily sludge had a water content of 74.83% and an oil content of 8.62% (as received). The original equipment had a residual solid phase oil content of 3.58% (dry basis) after treatment, and its processing capacity was only 64.2% of the design capacity. After treatment using the method described in this application, the residual solid phase oil content was 0.98% (dry basis), the recovered oil had a water content of 0.73%, and the mechanical impurity content was 0.24%, achieving a processing capacity of 102.8% of the design capacity.

[0189] As shown in Figure 1, the second aspect of this embodiment provides a chemical thermal washing device for oily sludge to implement the above method. This device includes a crushing and vibrating screen device, a first centrifugal separation device 4, a preheating liquefaction device 5, a reaction device 6, a flash demulsification tank 7, and a multi-stage separation device; wherein...

[0190] The crushing and vibrating screen device is used to crush, screen and clean the oily sludge 21 in the raw material storage tank 1 to obtain the first solid phase product and the first liquid phase product.

[0191] The first centrifugal separation device 4 is used to perform a first centrifugal separation process on the first liquid phase product to obtain a second solid phase product and a second liquid phase product.

[0192] The preheating liquefaction device 5 is used to preheat and liquefy the second solid product to obtain the first mixed product.

[0193] The reaction apparatus 6 is used to mix the first mixed product with the catalytic conditioning agent 23 and carry out a hot water hydrolysis reaction to obtain the second mixed product;

[0194] It is also used to flash evaporate the second mixture to obtain the third mixture;

[0195] Flash demulsifier 7 is used to mix the second liquid phase product, the third mixed product and the demulsifier 24, and perform demulsification treatment to obtain the fourth mixed product.

[0196] A multi-stage separation device is used to perform multi-stage separation processing on the fourth mixed product to obtain a first aqueous phase product, a first oil phase product, and a third solid phase product.

[0197] Specifically, the first separation device includes a crusher 2 and a three-stage vibrating screen 3 connected to each other. The inlet of the crusher 2 can be connected to the raw material storage tank 1 via a gantry crane or a transport device, and the liquid phase outlet of the three-stage vibrating screen 3 can be connected to the first centrifugal separation device 4 via a centrifugal pump.

[0198] Specifically, the crushing and vibrating screen device is connected in sequence to the first centrifugal separation device 4, the preheating liquefaction device 5, the reaction device 6, the flash demulsification tank 7, and the multi-stage separation device;

[0199] Specifically, the first centrifugal separation device 4 can be a horizontal spiral centrifugal separator, a vertical centrifugal separator, or a disc centrifugal separator, and its solid phase outlet can be connected to the preheating liquefaction device 5 through a screw pump.

[0200] Furthermore, the crushing and vibrating screen device also includes a water storage tank 17 for primary and secondary rinsing, and the obtained first aqueous product can be fed into the water storage tank 17 for recycling.

[0201] Specifically, the preheating liquefaction device 5 is a preheating liquefaction tank. The preheating liquefaction tank has a fully enclosed structure, with a conical hopper at the bottom, a steam distribution pipe in the middle, and a cylindrical tank with a spherical head at the top. The upper part of the cylindrical tank is equipped with a mud inlet, a suction valve and an exhaust pipe at the top, and a steam and flash steam converging into the steam distribution pipe at the bottom.

[0202] Furthermore, reaction device 6 is also used for:

[0203] After the hot hydrolysis reaction is completed, a first-stage flash evaporation is performed until the pressure difference between the equipment where step 6 is performed and the first pressure difference between the equipment where step 5 is performed is less than 0.01 MPa. Then, the first-stage flash evaporation is stopped, and the flash vapor generated by the first-stage flash evaporation is transported to the hot liquefaction unit.

[0204] When the first pressure difference is greater than 0.01 MPa, secondary flash evaporation is carried out until the first pressure difference is less than 0.01 MPa or the temperature of the secondary flash evaporation is not greater than 102℃~105℃. Then, the secondary flash evaporation is stopped, and the flash evaporation product is used as the third mixed product. The flash vapor generated by the secondary flash evaporation is transported to the gas processing unit.

[0205] The apparatus also includes a gas processing unit; the gas processing unit is used for:

[0206] The flash vapor generated by the secondary flash evaporation is condensed and adsorbed to obtain the first gaseous product and the fourth liquid product.

[0207] Specifically, the reaction device 6 can be a reaction vessel. The reaction device 6 is equipped with a first pressure relief valve and a second pressure relief valve. The first pressure relief valve is used for primary flash evaporation, and its outlet is connected to the preheating liquefaction device 5. The second pressure relief valve is used for secondary flash evaporation, and its outlet is connected to the gas processing device.

[0208] Furthermore, the multi-stage separation unit includes a second centrifugal separation unit 8, an oil-water storage tank 9, and a three-phase separation unit 10, wherein:

[0209] The second centrifugal separation device 8 is used to perform a second centrifugal separation process on the first mixed product to obtain a fifth solid phase product and a third liquid phase product.

[0210] The third liquid product is transported to the three-phase separation device 10 through the oil-water storage tank 9. The first inlet of the oil-water storage tank 9 is connected to the outlet of the second centrifugal separation device 8, and the outlet of the second centrifugal separation device 8 is connected to the inlet of the three-phase separation device 10.

[0211] The three-phase separation device 10 is used to perform three-phase separation treatment on the fifth liquid phase product to obtain the first aqueous phase product, the first oil phase product and the third solid phase product.

[0212] Furthermore, the gas treatment device includes a condenser, an activated carbon adsorption unit 14, and an induced draft fan 15; wherein

[0213] The condenser 13 is used to condense the flash vapor generated by the secondary flash evaporation to produce the fourth liquid phase product and the second gas phase product; the liquid phase outlet of the condenser 13 is connected to the second liquid inlet of the oil-water storage tank 9.

[0214] The activated carbon adsorption device 14 is used to adsorb the second gas phase product with activated carbon to obtain the first gas phase product. The first gas phase product is the waste gas 26 of this device, which is discharged by the induced draft fan 15.

[0215] Specifically, the first aqueous phase product and the third solid phase product are wastewater 27 and waste residue 25 discharged from this device, respectively.

[0216] Furthermore, the gas processing device also includes a cooling tower 12, through which the condensing device 13 exchanges heat.

[0217] Specifically, the second centrifugal separation device 8 can be a horizontal spiral centrifuge, a vertical centrifuge, or a disc centrifuge; the three-phase separation device 10 uses a disc centrifuge.

[0218] Furthermore, the device also includes an oil storage tank 16, through which the first oil phase product, as recovered oil 28, can be stored and recycled.

[0219] This embodiment provides a chemical thermal washing device for oily sludge, which can realize the method provided in the above embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0220] Finally, it should be noted that other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and alterations may be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A method of chemical hot washing of oil-containing sludge, characterized in that, The method comprises the following steps: Step 1, the oily sludge is crushed, screened and cleaned to obtain a first solid phase product and a first liquid phase product; Step 2, the first liquid phase product is subjected to first centrifugal separation to obtain a second solid phase product and a second liquid phase product; Step 3, the second solid phase product is subjected to preheating and liquefaction to obtain a first mixed product; Step 4, the first mixed product is mixed with a catalytic modifier and subjected to thermal hydrolysis to obtain a second mixed product; Step 5, the second mixed product is subjected to flash evaporation to obtain a third mixed product; Step 6, the second liquid phase product and the third mixed product are mixed with a demulsifier and subjected to demulsification to obtain a fourth mixed product; Step 7, the fourth mixed product is subjected to multi-stage separation to obtain a first water phase product, a first oil phase product and a third solid phase product.

2. The method of claim 1, wherein, The step 5 specifically comprises the following steps: Step 5-1, after the thermal hydrolysis is completed, primary flash evaporation is performed until the pressure of an equipment in which the step 6 is performed and a first pressure of an equipment in which the step 5 is performed have a pressure difference less than 0.01 MPa, and then the primary flash evaporation is stopped; Step 5-2, when the first pressure difference is greater than 0.01 MPa, secondary flash evaporation is performed until the first pressure difference is less than 0.01 MPa or the temperature of the secondary flash evaporation is not greater than 102-105 DEG C, and then the secondary flash evaporation is stopped, and flash evaporation pre-charge is taken as the third mixed product.

3. The method of claim 2, wherein, The step 5-1 further comprises the following step: The flash steam generated by the primary flash evaporation is used to provide heat for the thermal hydrolysis of the step 4.

4. The method according to any one of claims 1-3, characterized in that, The catalytic modifier is composed of a dispersing agent, a polyoxyethylene ether, a high-valence electrolyte and a photosensitizer, and has a mass ratio of 30-50:10-20:10-20:20-40 and an addition amount of 0.5-3% (w); The high-valence electrolyte comprises one or more of iron sulfate, iron chloride and calcium chloride; the dispersing agent comprises sodium silicate; and the photosensitizer comprises titanium dioxide.

5. The method according to any one of claims 1-4, characterized in that, The demulsifier is composed of sodium bicarbonate, a cationic surfactant, a non-ionic surfactant and carbamide, and has a mass ratio of 30-50:10-20:10-20-40 and an addition amount of 0.5-3% (w); The cationic surfactant comprises one or more of sodium dodecyl benzene sulfonate and cetyl ammonium chloride; and the non-ionic surfactant comprises a polyoxyethylene ether.

6. The method of claim 1 or 2, wherein, The step 7 comprises the following steps: The fourth mixed product is subjected to second centrifugal separation to obtain a fifth solid phase product and a third liquid phase product; The third liquid phase product is subjected to three-phase separation to obtain the first water phase product, the first oil phase product and the third solid phase product.

7. The method of claim 6, wherein, The step 5-2 further comprises the following step: The flash steam generated by the secondary flash evaporation is subjected to condensation and adsorption to obtain a first gas phase product and a fourth liquid phase product; and the fourth liquid phase product is subjected to the three-phase separation.

8. The method according to any one of claims 1-7, characterized in that, In the step 4, the reaction temperature is 170-230 DEG C, and the reaction time is 20-60 min.

9. The method according to any one of claims 1-7, characterized in that, The stirring speed in the step 6 is 100-200 r / min, and the reaction time is 20-30 min.

10. The method according to any one of claims 1-7, characterized in that, The step 1 specifically comprises: The oil sludge in the raw material storage tank is crushed by a crusher and subjected to primary leaching to obtain a fourth solid phase product; The fourth solid phase product is subjected to multi-stage vibration screening separation and then subjected to secondary leaching to obtain the first solid phase product, and the waste liquid obtained by the primary leaching and the secondary leaching is used as the first liquid phase product.

11. A chemical heat washing apparatus for oil-containing sludge for carrying out the method according to any one of claims 1 to 7, comprising: The crushing and screening machine device, the first centrifugal separation device, the preheating and liquefaction device, the reaction device, the flash distillation and demulsification tank, and the multi-stage separation device; The crushing and screening machine device is used for crushing, screening and cleaning the oil-containing sludge to obtain the first solid phase product and the first liquid phase product. The first centrifugal separation device is used for performing first centrifugal separation on the first liquid phase product to obtain the second solid phase product and the second liquid phase product. The preheating and liquefaction device is used for preheating and liquefying the second solid phase product to obtain a first mixed product. The reaction device is used for mixing the first mixed product with a catalytic modifier to perform a thermal hydrolysis reaction and obtain a second mixed product. The reaction device is also used for performing flash distillation on the second mixed product to obtain a third mixed product. The flash distillation and demulsification tank is used for mixing the second liquid phase product, the third mixed product and a demulsifier to perform demulsification and obtain a fourth mixed product. The multi-stage separation device is used for performing multi-stage separation on the fourth mixed product to obtain a first water phase product, a first oil phase product and a third solid phase product. The reaction device is also used for:

12. The apparatus of claim 11, wherein, After the completion of the thermal hydrolysis reaction, primary flash distillation is performed until the pressure of the device in which the step 6 is performed and the first pressure of the device in which the step 5 is performed have a difference of less than 0.01 MPa, and then the primary flash distillation is stopped, and the flash steam generated by the primary flash distillation is transported to the preheating and liquefaction device; When the first pressure difference is greater than 0.01 MPa, secondary flash distillation is performed until the first pressure difference is less than 0.01 MPa or the temperature of the secondary flash distillation is not greater than 102-105 DEG C, and then the secondary flash distillation is stopped, the flash distillation product is used as the third mixed product, and the flash steam generated by the secondary flash distillation is transported to the gas treatment device. The device also comprises a gas treatment device, and the gas treatment device is used for: condensing and adsorbing the flash steam generated by the secondary flash distillation to obtain a first gas phase product and a fourth liquid phase product. The multi-stage separation device comprises a second centrifugal separation device, an oil-water storage tank and a three-phase separation device, wherein:

13. The apparatus of claim 12, wherein, The second centrifugal separation device is used for performing second centrifugal separation on the first mixed product to obtain a fifth solid phase product and a third liquid phase product; The third liquid phase product is transported to the three-phase separation device through the oil-water storage tank, the first liquid inlet of the oil-water storage tank is connected with the liquid outlet of the second centrifugal separation device, and the liquid outlet of the second centrifugal separation device is connected with the liquid inlet of the three-phase separation device; ​ The three-phase separation device is used for three-phase separation treatment of the fifth liquid phase product to obtain a first water phase product, a first oil phase product and a third solid phase product.

14. The apparatus of claims 11-13, wherein, The gas treatment device comprises a condensing device, an activated carbon adsorption device and an air blower. The condensing device is used for condensing treatment of flash steam generated by the secondary flash evaporation to generate a fourth liquid phase product and a second gas phase product. The activated carbon adsorption device is used for activated carbon adsorption of the second gas phase product to obtain the first gas phase product, and the first gas phase product is discharged through the air blower.

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