A system and process for treating oil-based slurry mixed with solid particles

Abstract

The present application discloses a system and a process for treating oil-based slurry mixed with solid particles, which belongs to the technical field of solid waste treatment. The treatment system includes a pipeline; a pretreatment device for providing oil-based slurry; an oxygen-free distillation device, including a heating device and a gas-solid separation device, the heating device is connected to the pretreatment device, and the gas-solid separation device is connected to the heating device; an overheating separation device, including a steam generating device and a filtering separation device, the filtering separation device is connected to the gas-solid separation device, the steam generating device is connected to the filtering separation device and the heating device; a steam fractionation device for condensation fractionation. The treatment process includes: starting the pretreatment device, the oxygen-free distillation device, the overheating separation device, and the steam fractionation device, heating the oil-based slurry and separating the gas and solid, filtering and separating the gas and solid again, and finally condensing and fractionating. The present application can pretreat the slurry, effectively treat the oil-based slurry into oil, water and solid particles that meet the requirements for discharge, and has the advantages of energy saving and emission reduction.

Description

Technical Field

[0001] The present application belongs to the technical field of solid waste treatment, and in particular, relates to a system and process for treating an oil-based slurry mixed with solid particles. Background Art

[0002] Oil-based cuttings, also known as oil-based drilling cuttings, are solid wastes produced during the oil drilling process through the contact between drilling fluid and formation rock. With the continuous exploration and development of shale gas, a large amount of hazardous waste - oil-based cuttings - is generated during the drilling process. For the shale gas drilling process, the treatment of oil-based cuttings is an important environmental issue. If they are not treated harmlessly, they will cause serious pollution to the oil and gas field environment. The oil-based cuttings generated in the traditional drilling process are first dehydrated on the drilling platform and then sent to the hazardous waste treatment plant. The oil-based cuttings entering the hazardous waste treatment plant have a low liquid content and a certain degree of dispersibility, and can be directly processed in the rotary kiln.

[0003] As the market changes, the oil-based rock cuttings dehydration process has been gradually cancelled on drilling platforms. The oil-based rock cuttings produced exist in a slurry state with a high liquid content. These oil-based rock cuttings are then sent to hazardous waste treatment plants for treatment. Since the oil-based rock cuttings slurry contains a large amount of oil and water, and contains a variety of surfactants, it is in a viscous emulsified state and difficult to separate. The existing hazardous waste treatment plants built with oil-based rock cuttings powder will not be able to adapt to the treatment of oil-based rock cuttings slurry. The oil-based rock cuttings treatment industry is in urgent need of new treatment technologies. Summary of the invention

[0004] The present application aims to at least to some extent solve the technical problem of lack of hazardous waste treatment of oil-based rock cuttings slurry. To this end, the present application provides an oil-based slurry treatment system and treatment process mixed with solid particles. By establishing a pretreatment device and process for the oil-based slurry, the slurry can be pretreated and the oil-based slurry can be effectively treated into oil, water and solid particles that meet the requirements for discharge. It is suitable for existing drilling process technology and has the advantages of energy saving and emission reduction.

[0005] In a first aspect, an embodiment of the present application provides an oil-based slurry treatment system mixed with solid particles, which includes a pipeline, and:

[0006] A pre-treatment device for providing oil-based slurry to connected equipment;

[0007] The oxygen-free distillation equipment comprises a heating device with an inlet and an outlet, and a gas-solid separation device with a solid particle outlet and a steam outlet, wherein the inlet of the heating device is connected to the pretreatment device, and the gas-solid separation device is connected to the outlet of the heating device;

[0008] The superheat separation device comprises a steam generating device for providing steam, a filtering and separating device for filtering solid particles, the filtering and separating device is provided with a second solid particle outlet and a second steam outlet, the filtering and separating device is connected to the first steam outlet through a pipeline, the steam generating device is connected to the pipeline between the filtering and separating device and the gas-solid separating device, and the steam generating device is connected to the inlet of the heating device;

[0009] The steam fractionation device is used for condensing and fractionating the steam, and the steam fractionation device is connected with the second steam outlet.

[0010] In an optional embodiment, the steam generating device includes a steam generator and a steam heater, the steam heater is used to heat the steam into superheated steam, the steam heater is arranged on the pipeline between the steam generator and the filtering and separating device, and the steam generator is connected to the inlet of the heating device.

[0011] In an optional embodiment, the filtering and separation device is provided with multiple stages, the pore size of the filter material layer of the upper filtering and separation device in adjacent stages is larger than the pore size of the filter material layer of the lower filtering and separation device, a flow valve is provided between each stage of the filtering and separation device and the steam generating device, the filtering and separation device is provided with a temperature detection device, and a feedback control loop is formed between the flow valve and the temperature detection device.

[0012] In an alternative embodiment, the steam fractionation apparatus comprises:

[0013] A primary condensing device, used for fractionating condensed oil, the primary condensing device is connected to the second steam outlet, and the primary condensing device is provided with a water vapor outlet and a condensed oil outlet;

[0014] The secondary condensing device is used for fractionating condensed water. The secondary condensing device is connected to the water vapor outlet. The secondary condensing device is provided with a condensed water outlet and a non-condensable gas outlet.

[0015] In an optional embodiment, the pre-processing device comprises:

[0016] A raw material mixing device, used for mixing oil-based slurry and dry material, wherein the dry material is solid particles discharged from the solid particle outlet 1 and the solid particle outlet 2;

[0017] A feeding device, used for continuously supplying oil-based slurry to the raw material mixing device;

[0018] The mixing and conveying device is used for conveying the mixed material of the oil-based slurry and the dry material to the heating device, and the mixing and conveying device is connected to the raw material mixing device.

[0019] In an optional embodiment, the pretreatment equipment also includes a dry material reinjection pipe fitting and a humidity detection device. The dry material reinjection pipe fitting includes a pipeline connecting solid particle outlet one and solid particle outlet two to the raw material mixing device, and a regulating valve installed on the pipeline. A feedback control loop is formed between the humidity detection device and the regulating valve, and the humidity detection device is connected to the raw material mixing device or the mixing conveying device.

[0020] In an optional embodiment, the raw material mixing device is provided with an oil-water vapor outlet, and the oil-water vapor outlet is connected to the filtering and separating device.

[0021] In an optional embodiment, in the heating device, the inner wall in contact with the mixed material is provided with a non-stick coating.

[0022] In a second aspect, an embodiment of the present application provides a treatment process for oil-based slurry mixed with solid particles, which uses the above-mentioned oil-based slurry treatment system mixed with solid particles, and the treatment process includes:

[0023] The pretreatment device is turned on, and the solid particles discharged from the oxygen-free distillation device and the superheat separation device are added into the oil-based slurry for mixing;

[0024] The oxygen-free distillation equipment is turned on to perform distillation by heating the oil-based slurry and then separating it into solid particles and primary steam, wherein the heating temperature is less than or equal to the boiling point of the oil-based slurry;

[0025] Turn on the superheat separation equipment to filter the primary steam and produce solid particles and secondary steam;

[0026] The steam fractionation equipment is turned on to grade and condense the secondary steam to produce condensed oil and condensed water.

[0027] In an optional embodiment, when the treatment is performed by the superheat separation device, the temperature of the steam generated by the steam generating device is greater than or equal to the temperature of the primary steam.

[0028] It can be seen from the above technical solution that the beneficial effects of this application are:

[0029] 1. The processing system of the present application provides oil-based slurry to the oxygen-free distillation device through a pretreatment device, heats the oil-based slurry through a heating device, processes the oil-based slurry into a mixed state of solid particles and steam, and then passes through a gas-solid separation device and separates it into solid particles and primary steam. The generated primary steam is kept at a high temperature by a steam generating device, and then separated by a superheating separation device to produce solid particles and secondary steam. The secondary steam is then condensed and fractionated into oil and water by a steam fractionation device. In this way, through the above-mentioned equipment, since the heating device and the steam generating device can maintain the high temperature of the oil-based slurry or steam, the separated solid particles are kept in a high-temperature dry state, so that the oil-based slurry can be effectively processed. Therefore, the present application can pre-treat the slurry by establishing a pretreatment device and process for oil-based slurry, and effectively treat the oil-based slurry into oil, water and solid particles that meet the discharge requirements, which is suitable for the existing drilling process and has the advantages of energy saving and emission reduction.

[0030] 2. The present application innovatively proposes a process for treating oil-based slurry, which first mixes the oil-based slurry and dry material, and uses the waste heat of the dry material to heat the oil-based slurry for the first time, thereby increasing the mixing effect. The oil-based slurry is then heated and maintained below the boiling point to effectively convert the oil-based slurry into a solid particle state and a steam state, thereby facilitating the separation of solid particles and primary steam. The primary steam is then further filtered and separated in a superheated state to produce solid particles and secondary steam, which are then condensed to effectively treat and separate the oil-based slurry into three phases: oil, water, and solid. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other embodiments and drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic diagram of an embodiment of an oil-based slurry treatment system mixed with solid particles according to the present invention is shown;

[0033] Figure 2 A schematic diagram of the steps of an embodiment of the pretreatment device of the present invention is shown;

[0034] Figure 3 A schematic diagram of an embodiment of the oxygen-free distillation equipment of the present invention is shown;

[0035] Figure 4 A schematic diagram showing the steps of an embodiment of the superheat separation device of the present invention is shown;

[0036] Figure 5A schematic diagram of the steps of an embodiment of the steam fractionation device of the present invention is shown;

[0037] Reference numerals: 100, pretreatment equipment; 110, feeding device; 111, forklift; 112, special ton barrel; 113, hopper; 114, shaftless screw conveyor; 120, dry material reinjection pipe fittings; 121, regulating valve; 130, raw material mixing device; 140, mixing material conveying device; 150, humidity detection device; 200, oxygen-free distillation equipment; 201, solid particle outlet 1; 202, steam outlet 1; 210, heating device; 220, gas-solid separation device; 221, kiln head cover; 222, cyclone separator; 300, overheating separation Equipment; 301, flow valve; 302, temperature detection device; 303, solid particle outlet two; 304, steam outlet two; 310, steam generating device; 311, steam generator; 312, steam heater; 320, filtering and separating device; 321, primary particle dust collector; 322, secondary particle dust collector; 400, steam fractionation equipment; 410, primary condensing device; 411, water-cooled valve one; 420, secondary condensing device; 421, water-cooled valve two; 430, tertiary condensing device; 440, quaternary condensing device; 500, pipeline. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] It should be noted that all directional indications in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between various components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0040] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0042] The present application is described below with reference to the accompanying drawings and specific embodiments:

[0043] Please refer to Figure 1 In the first aspect of the present application, an embodiment provides a system for treating oil-based slurry mixed with solid particles. The oil-based slurry usually contains oil, water (usually emulsified), fine-particle solid waste, organic clay, oil-soluble chemical treatment agent, etc. This embodiment is described by taking oil-based rock cuttings as an example. The treatment system is used for treating oil-based rock cuttings. The treatment system includes a pipeline 500, and the following connected by the pipeline 500: a pretreatment device 100, an oxygen-free distillation device 200, a superheat separation device 300 and a steam fractionation device. The pipeline 500 adopts a conventional pipe structure for transportation, such as a steel pipe, a PVC pipe, etc. The pretreatment device 100 is used to provide oil-based slurry to the connected equipment. For example, the pretreatment device 100 is a funnel and a pump for collecting slurry. The outlet of the funnel is connected to the oxygen-free distillation device 200 through a pipeline 500, and the oil-based slurry is pumped to the oxygen-free distillation device 200 by the pump; the oxygen-free distillation device 200 includes a heating device 210 with an inlet and an outlet, and a gas-solid separation device 220 with a solid particle outlet 201 and a steam outlet 202. The inlet of the heating device 210 is connected to the pretreatment device 100, and the oil-based slurry is injected into the heating device 210 through the pretreatment device 100. The heating device 210 has a cavity inside, and the oil The oil-based slurry enters the cavity through the inlet of the heating device 210, the oil-based slurry is heated in the heating device 210, the gas-solid separation device 220 is connected to the outlet of the heating device 210, and then the heated oil-based slurry is discharged from the outlet of the heating device 210 to the gas-solid separation device 220. At this time, the oil-based slurry is in a solid particle state and a steam state. The solid particle outlet 201 is located at the bottom of the gas-solid separation device 220, and the steam outlet 202 is located at the top of the gas-solid separation device 220. Finally, the solid particles are discharged from the solid particle outlet 201, and the primary steam is discharged to the superheating separation equipment 300 through the steam outlet 202.

[0044] The superheat separation device 300 includes a steam generating device 310 for providing steam, and a filtering and separating device 320 for filtering solid particles. The filtering and separating device 320 has a solid particle outlet 2 303 and a steam outlet 2 304. The filtering and separating device 320 is connected to the steam outlet 1 202 through a pipeline 500. The primary steam discharged from the steam outlet 1 202 enters the filtering and separating device 320 through the pipeline 500. The filtering and separating device 320 is an existing filter having a filter material layer. The primary steam passes through the filter material layer, and the fine particles remain in the filter material layer 1. side, and the steam continues to be discharged from the second steam outlet 304 after passing through the filter material layer; if the inlet of the filtration separation device 320 is arranged at its top, the second solid particle outlet 303 is arranged at the bottom of the filtration separation device 320, and the second steam outlet 304 is arranged at the top of the filtration separation device 320, and the filter material layer is provided with multiple and vertically spaced arrangements, after the primary steam enters the filtration separation device 320, it flows downward and flows laterally through the filter material layer, and then flows from the top of the filter material layer to the second steam outlet 304, forming secondary steam, and the secondary steam is discharged from the second steam outlet 304 to the distillation fractionation device. The steam generating device 310 is connected to the pipeline 500 between the filtering and separating device 320 and the gas-solid separating device 220. The steam generating device 310 is an existing steam generating device, and its steam outlet is connected to the pipeline 500 from the steam outlet 202 to the inlet of the filtering and separating device 320 through the pipeline 500. In this way, the steam generated by the steam generating device 310 can be mixed with the primary steam, participate in the steam treatment process of the oil-based slurry, and maintain a certain high temperature to avoid condensation of the steam of the oil-based slurry. The steam generating device 310 is connected to the inlet of the heating device 210. The steam generating device 310 is also connected to the inlet of the heating device 210 through another pipeline 500. The steam enters the heating device 210 to enhance the flow of the oil-based slurry in the cavity of the heating device 210. The steam fractionation device is used to condense and fractionate steam. The inlet of the steam fractionation device is connected to the steam outlet 304. The secondary steam enters the steam fractionation device. The distillation fractionation device adopts the existing water-cooled condensation fractionation device. The secondary steam is cooled by heat exchange by passing cold water. After cooling, the steam condenses to produce oil and water. The oil and water can be treated by conventional separation methods, and chemical additives can also be added to reduce the COD content in the water.

[0045] Existing hazardous waste treatment plants lack treatment equipment for oil-based slurries. This is because current hazardous waste treatment plants only treat dehydrated oil-based solid waste and are not suitable for slurry treatment. Slurry treatment is very difficult. On the one hand, during the heating process of oil-based slurries in existing rotary kilns, coking occurs on the inner wall of the kiln. As the coking occurs, the wall heat transfer coefficient drops sharply, which eventually causes the device to fail to operate and must be shut down for cleaning. On the other hand, during the heating process of oil-based solid waste, high-temperature oil-water mixed steam is continuously generated, and the steam carries A large amount of fine dust makes it difficult to separate gas and solid under high temperature conditions, the cost is high, the system operation is extremely unstable, and the oil content in the oil-water mixed steam has the characteristics of high boiling point and easy condensation, which is easy to clog the device; thirdly, the thermal separation of oil-based solid waste produces wastewater with extremely high COD concentration, and the COD concentration even reaches tens of thousands of milligrams per liter, which brings great difficulties to the subsequent wastewater treatment; fourthly, because the oil-based solid waste contains a large amount of surfactants, the surfactants enter the condensed oil-water mixture with the oil-water vapor, causing the condensed oil and water to be emulsified, and the oil and water are difficult to separate. In summary, there are certain difficulties in the current hazardous waste treatment of oil-based solid waste.

[0046] The present application provides oil-based slurry to the oxygen-free distillation device 200 through the pretreatment device 100, heats the oil-based slurry through the heating device 210, treats the oil-based slurry into a mixed state of solid particles and steam, and then passes through the gas-solid separation device 220 and separates it into solid particles and primary steam, the primary steam is a mixed oil-water steam with fine particles, the generated primary steam is kept at a high temperature by the steam generation device 310, and then separated by the superheat separation device 300 to produce solid particles and secondary steam, the secondary steam is then condensed and fractionated into oil and water by the steam fractionation device, so that through the above-mentioned equipment, since the heating device 210 and the steam generation device 310 can maintain the high temperature of the oil-based slurry or steam, the separated solid particles are kept in a high-temperature dry state, so that the oil-based slurry can be effectively treated. Therefore, the present application can pre-treat the slurry by establishing a pretreatment device and process for oil-based slurry, effectively treat the oil-based slurry into oil, water and solid particles that meet the discharge requirements, is suitable for the existing drilling process, and has the advantages of energy saving and emission reduction.

[0047] Please refer to Figure 2In an optional embodiment, the pretreatment device 100 includes: a raw material mixing device 130, a feeding device 110 and a mixing and conveying device 140. The raw material mixing device 130 is used to mix the oil-based slurry and the dry material. The dry material is the solid particles discharged from the solid particle outlet 1 201 and the solid particle outlet 2 303, which come from the oxygen-free distillation device 200 and the superheat separation device 300 respectively. The dry material has a high temperature. Due to the mixing of the high-temperature dry material, a certain amount of water vapor is evaporated by the sensible heat of the dry residue during the mixing process, so as to achieve the purpose of waste heat utilization. The raw material mixing device 130 adopts a double-shaft mixer, and other devices with stirring and mixing functions can also be adopted. In an optional embodiment, the raw material mixing device 130 is provided with an oil-water vapor outlet, such as the double-shaft mixer has a sealed top cover, and the water vapor outlet is arranged on the sealed top cover. The oil-water vapor outlet is connected to the inlet of the filtering and separating device 320 through a pipeline 500, and the steam generated in this way is conveyed to the filtering and separating device 320 for treatment.

[0048] In an optional embodiment, the feeding device 110 is used to continuously provide the oil-based slurry to the raw material mixing device 130. For example, the feeding device 110 is connected to the inlet of the raw material mixing device 130; the feeding device 110 includes a forklift 111 with a rotating disk, a special ton barrel 112, a hopper 113 and a shaftless screw conveyor 114. The oil-based slurry is transferred to the special ton barrel 112 by the forklift 111, and the oil-based rock cuttings slurry contained in the special ton barrel 112 is transported to the forklift 111. At the receiving hopper 113, the ton barrel is raised to the upper edge of the receiving hopper 113 under the lifting action of the lifting arm of the forklift 111, and the slurry in the barrel is poured into the receiving hopper 113 under the rotation action of the rotating arm. The special ton barrel 112 has a quick-opening barrel cover, which can be opened quickly. The special ton barrel 112 is provided with a fork groove for the fork arm of the forklift 111 to insert, and the slurry can be poured quickly. The forklift 111 with a rotating disk cooperates with the special ton barrel 112 to load materials, which is convenient and fast with high labor efficiency. The oil-based rock cuttings slurry entering the receiving hopper 113 is transported into the double-shaft mixer under the conveying action of the shaftless screw conveyor 114. The shaftless screw conveyor 114 has the function of not being easily blocked and entangled when conveying viscous slurry; at the same time, the high-temperature deoiled dry residue conveyed by the dry material reinjection pipe 120 enters the double-shaft mixer. Under the stirring action of the double-shaft mixer, the dry and wet materials are fully mixed. During the mixing, the stirring blades push the mixed material to the outlet of the raw material mixing device 130.

[0049] In an optional embodiment, the oil-based rock cuttings slurry from the well site has a high oil-water content and is in an emulsified state, which is not suitable for direct treatment in the rotary kiln. It needs to be pre-treated to a certain extent to reduce the liquid content of the slurry, reduce the viscosity of the material, and change the slurry into a powder material with a certain degree of dispersibility, and then transport the material to the oxygen-free distillation equipment 200. Specifically, the mixing and conveying device 140 is used to convey the mixed material of the oil-based slurry and the dry material to the heating device 210. The inlet of the mixing and conveying device 140 is connected to the outlet of the raw material mixing device 130 through the pipeline 500. The mixed material enters the hopper 113 set at the inlet of the mixing and conveying device 140 from the outlet. The oil-based slurry discharged from the hopper 113 is transported to the inlet of the heating device 210 by the mixing and conveying device 140. If the mixing and conveying device 140 uses an existing conveyor, the oil-based slurry is transported to the rotary kiln for heating by the conveyor.

[0050] In an optional embodiment, the pretreatment equipment 100 further includes a dry material reinjection pipe 120 and a humidity detection device 150. The dry material reinjection pipe 120 includes a pipeline 500 connecting the solid particle outlet 1 201 and the solid particle outlet 2 303 to the raw material mixing device 130, and a regulating valve 121 installed on the pipeline 500. A feedback control loop is formed between the humidity detection device 150 and the regulating valve 121. The humidity detection device 150 is connected to the raw material mixing device 130 or the mixing conveying device 140. The humidity detection device 150 uses a component analyzer, which can detect the liquid content of the mixed material and feed back the detection data to the regulating valve 121. The regulating valve 121 is an electric valve, such as a solenoid valve, which executes a pre-set program. When the detection data exceeds the preset value, the regulating valve 121 automatically opens, and the amount of dry material added is adjusted by the regulating valve 121, so as to control the humidity of the mixed material. In this way, the humidity of the mixed material can be controlled, the moisture content of the mixed material is stable, the workload is reduced, and the mixing efficiency is improved.

[0051] Please refer to Figure 3In an optional embodiment, in the heating device 210, the inner wall in contact with the mixed material is provided with a non-stick coating, and the heating device 210 adopts a rotary kiln. The rotary kiln adopts an indirect heating method, and a heating jacket is provided outside the kiln. The high-temperature flue gas generated by the combustion of the fuel burner is used to transfer heat to the oil-based slurry in the kiln through the wall of the rotary kiln by heat conduction. The slurry is continuously mixed and moved toward the discharge end under the rotation of the rotary kiln, and the oil and water are separated by heat at the same time. Since oil-based rock cuttings are prone to coking and wall attachment during heating, the heat transfer coefficient of the cylinder wall will decrease. In severe cases, it may even cause frequent shutdowns for cleaning, resulting in unsustainable operation of the device. In order to avoid scaling of the rotary kiln cylinder wall, the inner wall of the rotary kiln is coated with a high-temperature non-stick coating, such as Teflon high-temperature non-stick coating for coating the inner wall of the cylinder, and then the coating surface is subjected to special processing, such as sandblasting, aluminum spraying, etc., to make its surface denser, thereby improving the non-stick performance. The core material of Teflon coating is polytetrafluoroethylene (PTFE), which has good heat resistance and non-stick properties. It is a polymer material widely used in the manufacture of non-stick coatings. The treated inner wall does not stick to the oil-based slurry at high temperature, has stable heat transfer, good coating wear resistance, and a long secondary brushing cycle, which solves the problem of coking and wall attachment on the inner wall of the cylinder.

[0052] In an optional embodiment, the gas-solid separation device 220 includes a kiln head cover 221 and a cyclone separator 222. The deoiled dry residue and the oil-water mixed steam separated by heating and gasification in the rotary kiln enter the kiln head cover 221 together. The kiln head cover 221 is cylindrical, and an opening is arranged on the side of the kiln head cover 221 and is connected to the outlet of the heating device 210 through the opening. The deoiled dry residue produced by the oil-based slurry is discharged from the solid particle outlet 201 at the bottom of the kiln head cover 221 under the action of gravity, and the high-temperature oil-water mixed steam carries fine dust in the kiln head cover 221. The cyclone separator 222 is fixed at the top position in the kiln head cover 221, and its outer diameter is smaller than the kiln head cover 221. The cyclone separator 222 is provided with a steam inlet on the side, and its bottom end is a particle outlet, and its top end is a steam outlet 202. The mixed steam enters the cyclone separator 222, and under the action of centrifugal force, most of the dust is separated from the particle outlet at the bottom of the cyclone separator 222 and falls into the kiln head cover 221 and then discharged from the solid particle outlet 201. The mixed steam after dust removal is discharged from the steam outlet 202. The cyclone separator 222 is arranged inside the kiln head cover 221, which can ensure that the temperature of the dust collector is the same as the material temperature, and avoid oil and gas condensation and blockage. For dust with a particle size greater than 10μm, the dust removal efficiency of the cyclone separator 222 can reach about 95%. Most of the dust in the mixed steam is removed in the cyclone separator 222, which reduces the load of subsequent particle material dust removal and ensures the stable operation of the system.

[0053] Please refer to Figure 4In an optional embodiment, because the rotary kiln adopts a distillation method below the boiling point, the mixed steam out of the rotary kiln is in a saturated state, and a slight change in temperature and pressure will cause steam condensation. To avoid the occurrence of condensation, this process adopts a steam generating device 310, which includes a steam generator 311 and a steam heater 312. The steam heater 312 is used to heat the steam into superheated steam. The steam heater 312 is used to further heat the steam generating device 310 to about 500°C. The steam generating device 310 is connected to the filtering and separating device 310 through a pipeline 500. The steam heater 312 is provided on the pipe 500 between the steam generator 311 and the filtering and separating device 320. The generated steam is mixed with the primary steam to increase the temperature of the steam entering the filtering and separating device 320 to about 400°C, thereby generating a certain degree of superheat to avoid condensation of oil and gas. The steam outlet of the steam generator 311 is also connected to another pipe 500, and is connected to the inlet of the heating device 210 through the pipe 500. In this way, during the startup phase, the water vapor generated by the steam generator 310 can preheat the oil-based slurry in the heating device 210.

[0054] In an optional embodiment, the filtering and separating device 320 is provided with multiple stages, and the multiple stages of filtering and separating devices 320 are connected in sequence according to the process sequence of each stage, and each stage of filtering and separating device 320 is a filter with a filter material layer. In adjacent stages, the pore size of the filter material layer of the upper filtering and separating device 320 is larger than the pore size of the filter material layer of the lower filtering and separating device 320, and the steam outlet of the upper filtering and separating device 320 is connected to the inlet of the lower filtering and separating device 320. A flow valve 301 is provided on the pipeline 500 between each stage of filtering and separating device 320 and the steam generating device 310, and the filtering and separating device 320 is provided with a temperature detection device 302. A feedback control loop is formed between the flow valve 301 and the temperature detection device 302. The temperature detection device 302 adopts a temperature sensor, and the temperature sensor transmits temperature data to the flow valve 301. The flow valve 301 is an electric valve, such as a solenoid valve, which has a built-in execution program and can adjust the flow rate according to the temperature data, thereby adjusting the amount of water vapor supplied. This is convenient for automatically adjusting the temperature of the filtering and separating device 320 to keep the steam temperature constant.

[0055] In an optional embodiment, the multi-stage filtering and separation device 320 uses an existing particle dust collector with filtering function, including a first-stage particle dust collector 321 and a second-stage particle dust collector 322. The first-stage particle dust collector 321 uses quartz sand with a diameter of 2mm±0.2mm as the filter material layer, which is filled in the circular annular gap composed of inner and outer porous tubes, and the filter material layer thickness is about 200mm±0.2mm. The dust-containing mixed steam enters the inner tube from the outside of the porous tube through the quartz sand filter material layer, and the filter material layer intercepts part of the dust. When the dust accumulates to a certain extent, it is discharged through the solid particle outlet 2 303 under the action of gravity. The oil-water mixed steam after dust removal is collected in the upper clean air chamber through the inner tube of multiple filter tubes; the filter material layer that has been running for a long time will block the channel due to the accumulation of dust, and the water vapor generated by the steam generating device 310 enters the particle dust collector and is sprayed, and the filter material layer is sprayed intermittently at a fixed time to restore the ventilation performance of the filter material layer. The structure and operation mode of the secondary particle dust collector 322 are the same as those of the primary particle dust collector 321. The difference is that quartz sand is used as the filter material layer in the secondary particle dust collector 322, and the screening particle size is 1mm±0.2mm to remove finer dust. And through the two-stage particle dust collector, it has a high-efficiency separation effect.

[0056] Please refer to Figure 5 In an optional embodiment, the steam fractionation device 400 includes: a primary condensation device 410 and a secondary condensation device 420, both of which adopt existing water-cooled condensation fractionation devices, and cool the secondary steam by introducing cold water. The primary condensation device 410 is used to fractionate condensed oil, and the primary condensation device 410 is connected to the steam outlet 2 304, and the primary condensation device 410 has a water vapor outlet and a condensed oil outlet. After the high-temperature steam enters the primary condensation device 410 from the steam outlet 2 304 and is cooled, the oil is condensed and fractionated; the secondary condensation device 420 is used to fractionate condensed water, and the secondary condensation device 420 is connected to the water vapor outlet of the primary condensation device 410, and the secondary condensation device 420 has a condensed water outlet and a non-condensable gas outlet. After the water vapor discharged from the primary condensation device 410 enters the secondary condensation device 420 and is cooled, the water is condensed and fractionated, and the non-condensable gas is discharged from the non-condensable gas outlet.

[0057] In an optional embodiment, the primary condensing device 410 and the secondary condensing device 420 adopt a shell-and-tube heat exchanger. The oil-water mixed steam after dust removal enters the gas collecting box at the upper end of the primary condensing device 410, and the mixed steam flows downward through the inside of the shell and tube. At the same time, cooling water is introduced into the outside (jacket) of the shell and tube heat exchanger for cooling. The steam in the tube is partially condensed. The outlet material temperature of the primary condensing device 410 is detected by a temperature sensor. The temperature signal is transmitted to the water cooling valve 411 to automatically adjust the cooling water flow rate, and the outlet material temperature of the primary condensing device 410 is controlled at about 110°C. The oil and other organic matter above the boiling point of water are condensed into liquid, and the water vapor and below the boiling point are condensed into liquid. Organic matter with a boiling point of water remains in a vapor state; the secondary condensation device 420 is connected to the next process of the primary condensation device 410. The setting of the secondary condensation device 420 is the same as that of the primary condensation device 410. It is also provided with a water-cooling valve 421 for adjusting the flow rate of cooling water. The steam coming out of the lower end of the primary condensation device 410 enters the upper end of the secondary condensation device 420, and the outlet material temperature of the secondary condensation device 420 is controlled at about 90°C. Most of the water vapor is condensed into liquid water, and a small amount of organic matter with a boiling point close to that of water enters the water phase. The remaining gaseous organic matter and non-condensable gases are discharged from the non-condensable gas outlet at the lower end of the secondary condensation device 420 to be burned to recover heat. In an optional embodiment, a tertiary condensation device 430 and a quaternary condensation device 440 are also included. The liquid oil flowing out from the lower end of the primary condensation device 410 enters the tertiary condensation device 430, is further cooled to a safe storage temperature and then transported to a storage tank for storage, and the condensed water flowing out from the lower end of the secondary condensation device 420 enters the quaternary condensation device 440, is further cooled to room temperature and then transported to a condensed water storage tank.

[0058] The second aspect of the present application provides a treatment process for oil-based slurry mixed with solid particles, which uses the above-mentioned oil-based slurry treatment system mixed with solid particles. The treatment process includes:

[0059] S1. Start the pretreatment equipment 100, add the solid particles discharged from the anaerobic distillation equipment 200 and the superheated separation equipment 300 into the oil-based slurry for mixing; for example, the deoiled high-temperature dry residue produced in the anaerobic distillation equipment 200 and the superheated separation equipment 300 is mixed with the oil-based rock chip slurry for dry and wet mixing. Since the deoiled high-temperature dry residue has hydrophobic and lipophilic properties, it has good workability when mixed with the oil-based rock chip slurry. Since the deoiled dry residue has been sieved and processed, the particle size is uniform, the mixed material has good dispersion, and is easy to be processed by the rotary kiln. The deoiled high-temperature dry residue comes from the anaerobic distillation equipment 200 and the superheated separation equipment 300, the raw materials are easy to obtain, the cost is low, and the high-temperature dry residue is used for mixing. During the mixing process, the sensible heat of the dry residue is utilized to evaporate part of the water, and the waste heat of the material is utilized, thereby saving energy and reducing consumption.

[0060] S2. Start the oxygen-free distillation equipment 200, distill by heating the oil-based slurry, and then separate it into solid particles and primary steam, wherein the heating temperature is less than or equal to the boiling point of the oil-based slurry; in order to further reduce the problem of coking on the inner wall of the cylinder, the process adopts medium-temperature distillation technology, that is, controlling the temperature in the kiln near the upper limit of the boiling range of the oil, lower than the boiling point, which can ensure the complete separation of the oil and slag without overheating, and avoid the cracking and coking of the oil due to excessive temperature; the gas-solid separation device 220 adopts a high-efficiency cyclone separator 222, which can separate a large amount of dust, effectively reducing the load of subsequent particle material dust removal, and is an important link in the entire gas-solid separation.

[0061] S3. Turn on the superheat separation device 300 to filter the primary steam to produce solid particles and secondary steam. In an optional embodiment, when the superheat separation device 300 is used for processing, the temperature of the steam generated by the steam generating device 310 is greater than or equal to the temperature of the primary steam. The high-temperature mixed steam entering the filtering and separating device 320 is further heated by the steam generating device 310, so that the mixed steam has a certain degree of superheat in the gas-solid separation device 220 to prevent the filter material layer from being blocked by condensation due to oil and gas. At the same time, the superheated water vapor is used as the heating medium when the system is started to preheat the filtering and separating device 320. The high-temperature superheated water vapor is used as the injection air source for the filter material layer to prevent the filter material layer from being blocked by condensation while the filter material layer is reversely sprayed. At the same time, the amount of superheated steam added is automatically adjusted by the water vapor flow valve 301 to ensure that the filtering and separating device 320 has a constant temperature. The multi-stage superheat separation device 300 is used, through graded filtration, and a uniquely designed dust removal structure is used, which has good dust removal effect, is not easy to clog, and has stable operation. The filter separator uses quartz sand as the filter material layer. Compared with other gas-solid separation methods, it can adapt well to high-temperature conditions, the raw materials are easy to obtain, and the operation and maintenance costs are greatly reduced. In order to prevent the occurrence of combustion and explosion accidents of high-temperature oil and gas, the high-temperature oil-water mixed steam needs to be in a reducing atmosphere during the gas-solid separation process. The present application uses water vapor to avoid the occurrence of combustion and explosion accidents, and has a certain degree of safety.

[0062] S4, open the steam fractionation equipment 400, condense the secondary steam in stages, and produce condensed oil and condensed water; according to the characteristics of different boiling points of each material in the oil-based slurry, control the condensation temperature separately, so that a large amount of organic matter with a boiling point higher than water is condensed into the oil phase, and some organic matter with a boiling point lower than water is kept in gaseous state for recovery and combustion, and then separate the condensed water, thereby controlling the COD concentration of the wastewater at a low level to achieve the purpose of clean production. This process is based on the principle that various substances in the mixed steam have different boiling points, and controls the condensation temperature in stages, so that the COD content of the separated wastewater is greatly reduced, and the COD content of the wastewater is controlled while condensing the steam. The outlet temperature control of the steam fractionation equipment 400 is the key to controlling the COD concentration in the condensed wastewater. In order to reduce the COD concentration of the wastewater, the outlet temperature of the steam fractionation equipment 400 can be further reduced and the outlet temperature of the steam fractionation equipment 400 can be increased, so that the distillation range of the wastewater becomes narrower, thereby reducing the COD concentration of the wastewater, reducing the difficulty and cost of subsequent wastewater treatment, and having obvious energy-saving and emission reduction effects. Recycling and burning non-condensable organic gases is also one of the effective measures to control COD in wastewater. It can control the emission of organic gases while recycling energy, thus achieving the effect of energy conservation and emission reduction.

[0063] Existing hazardous waste treatment plants treat dehydrated oil-based solid waste and lack a treatment process for oil-based slurry. The present application innovatively proposes a process for treating oil-based slurry, which first mixes the oil-based slurry and dry material, and uses the waste heat of the dry material to heat the oil-based slurry for the first time, thereby increasing the mixing effect. The oil-based slurry is then heated and maintained below the boiling point to effectively convert the oil-based slurry into a solid particle state and a steam state, thereby facilitating the separation of solid particles and primary steam. The primary steam is further filtered and separated in a superheated state to produce solid particles and secondary steam, which are then condensed to effectively treat and separate the oil-based slurry into three phases: oil, water, and solid. Each treatment link operates stably, with the advantages of both energy saving and emission reduction, meeting environmental protection requirements.

[0064] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", "optional example" or "optional implementation" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0065] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0066] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A system for treating oil-based slurry mixed with solid particles, characterized in that: The invention comprises a pipeline (500), and the following connected through the pipeline (500): A pre-treatment device (100) for providing oil-based slurry to connected devices; The oxygen-free distillation device (200) comprises a heating device (210) having an inlet and an outlet, and a gas-solid separation device (220) having a solid particle outlet (201) and a steam outlet (202), wherein the inlet of the heating device (210) is connected to the pretreatment device (100), and the gas-solid separation device (220) is connected to the outlet of the heating device (210); A superheat separation device (300), comprising a steam generating device (310) for providing steam, and a filtering and separating device (320) for filtering solid particles, the filtering and separating device (320) having a second solid particle outlet (303) and a second steam outlet (304), the filtering and separating device (320) being connected to the first steam outlet (202) via a pipeline (500), the steam generating device (310) being connected to the pipeline (500) between the filtering and separating device (320) and the gas-solid separating device (220), and the steam generating device (310) being connected to an inlet of the heating device (210); A steam fractionation device (400) for condensing and fractionating steam, wherein the steam fractionation device (400) is in communication with the second steam outlet (304); The steam generating device (310) comprises a steam generator (311) and a steam heater (312); the steam heater (312) is used to heat steam into superheated steam; the steam heater (312) is arranged on a pipeline (500) between the steam generator (311) and the filtering and separating device (320); the steam generator (311) is in communication with an inlet of the heating device (210).

2. The oil-based slurry processing system mixed with solid particles according to claim 1, characterized in that: The filtering and separating device (320) is provided with multiple stages. In adjacent stages, the pore size of the filtering layer of the upper filtering and separating device (320) is larger than the pore size of the filtering layer of the lower filtering and separating device (320). A flow valve (301) is provided between each stage of the filtering and separating device (320) and the steam generating device (310). The filtering and separating device (320) is provided with a temperature detecting device (302). A feedback control loop is formed between the flow valve (301) and the temperature detecting device (302).

3. The oil-based slurry processing system mixed with solid particles according to any one of claims 1-2, characterized in that: The steam fractionation device (400) comprises: A primary condensing device (410) is used to fractionate condensed oil, the primary condensing device (410) is connected to the second steam outlet (304), and the primary condensing device (410) has a water vapor outlet and a condensed oil outlet; The secondary condensation device (420) is used to fractionally distill condensed water, the secondary condensation device (420) is connected to the water vapor outlet, and the secondary condensation device (420) has a condensed water outlet and a non-condensable gas outlet.

4. The oil-based slurry processing system mixed with solid particles according to any one of claims 1-2, characterized in that: The pre-processing device (100) comprises: A raw material mixing device (130) for mixing oil-based slurry and dry material, wherein the dry material is solid particles discharged from the solid particle outlet 1 (201) and the solid particle outlet 2 (303); A feeding device (110) for continuously supplying oil-based slurry to the raw material mixing device (130); The mixing material conveying device (140) is used to convey a mixture of oil-based slurry and dry material to the heating device (210), and the mixing material conveying device (140) is connected to the raw material mixing device (130).

5. The oil-based slurry processing system mixed with solid particles according to claim 4, characterized in that: The pretreatment equipment (100) further comprises a dry material reinjection pipe fitting (120) and a humidity detection device (150); the dry material reinjection pipe fitting (120) comprises a pipeline (500) connecting the solid particle outlet 1 (201) and the solid particle outlet 2 (303) to the raw material mixing device (130), and a regulating valve (121) installed on the pipeline (500); a feedback control loop is formed between the humidity detection device (150) and the regulating valve (121); the humidity detection device (150) is connected to the raw material mixing device (130) or the mixed material conveying device (140).

6. The oil-based slurry processing system mixed with solid particles according to claim 4, characterized in that: The raw material mixing device (130) is provided with an oil-water vapor outlet, and the oil-water vapor outlet is connected to the filtering and separating device (320).

7. The oil-based slurry treatment system mixed with solid particles according to claim 1, characterized in that: In the heating device (210), the inner wall in contact with the mixed material is provided with a non-stick coating.

8. A process for treating an oil-based slurry mixed with solid particles, characterized in that: The oil-based slurry treatment system mixed with solid particles according to any one of claims 1 to 7 is used, and the treatment process includes: The pretreatment device (100) is started, and the solid particles discharged from the oxygen-free distillation device (200) and the superheat separation device (300) are added to the oil-based slurry for mixing; The oxygen-free distillation device (200) is turned on to perform distillation by heating the oil-based slurry, and then separate the oil-based slurry into solid particles and primary steam, wherein the heating temperature is less than or equal to the boiling point of the oil-based slurry; Starting the superheat separation device (300) to filter the primary steam to produce solid particles and secondary steam; The steam fractionation device (400) is turned on to perform fractional condensation on the secondary steam to produce condensed oil and condensed water.

9. The process for treating oil-based slurry mixed with solid particles according to claim 8, characterized in that: When the superheat separation device (300) is used for processing, the temperature of the steam generated by the steam generating device (310) is greater than or equal to the temperature of the primary steam.

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