An industrial waste salt treatment and purification device

Abstract

The application discloses an industrial waste salt treatment and purification device, which comprises multistage pyrolysis furnaces, and a gas-solid separator is arranged between every two adjacent pyrolysis furnaces; the gas-solid separator comprises an upper section, a middle section and a lower section which are sequentially communicated from top to bottom; the upper section is provided with a separation feed pipe and an exhaust pipe, the exhaust pipe extends downward into the middle section; the middle section is composed of an outer cylinder and an inner cylinder which is rotatably arranged in the outer cylinder, the inner cylinder is connected with a rotary driving assembly, and the inner wall of the inner cylinder is provided with a spiral protrusion; and the lower section is provided with a separation discharge pipe. By arranging the gas-solid separator between the multistage pyrolysis furnaces, the pyrolysis gas and the solid salt powder are separated, the risk of causing deflagration of the pyrolysis gas containing combustible gas into the next stage is avoided, the clean pyrolysis gas after separation can be used as fuel to supply the next stage pyrolysis furnace, energy recycling is realized, and the gas-solid separation efficiency is remarkably improved.

Description

Technical Field

[0001] This invention relates to the resource utilization of industrial waste salt, specifically to an industrial waste salt treatment and purification device, and more particularly to an improved gas-solid separator structure for separating gas-solid mixtures in a waste salt pyrolysis system. Background Technology

[0002] Industrial production processes, such as chemical, pesticide, and pharmaceutical industries, generate large quantities of solid waste salts. These wastes are produced in enormous quantities annually, are complex in composition, and are highly toxic and hazardous, posing a significant challenge to hazardous waste management. Faced with increasingly stringent environmental policies, the harmless treatment and resource utilization of industrial waste salts have become urgent issues to be addressed.

[0003] Pyrolysis is one of the mainstream technologies for industrial waste salt treatment. Its principle is to use a pyrolysis furnace to thermally decompose the organic matter in the waste salt under high temperature and oxygen-deficient conditions, generating combustible gases (CH4, H2, CO, etc.) and solid salt residue. The pyrolysis products are a gas-solid mixture—that is, the high-temperature pyrolysis gas carries a large amount of solid salt powder. In practical engineering, the separation effect between the pyrolysis gas and the solid salt powder directly affects the operating efficiency and safety of subsequent processes.

[0004] If the pyrolysis gas contains too much salt powder, when it is fed into the burner as fuel, the salt powder will wear down the burner nozzle, corrode the high-temperature pipes, and increase the exhaust gas treatment load. If too much pyrolysis gas is mixed into the solid salt powder, the combustible components carried by the pyrolysis gas can easily cause deflagration or even explosion when they enter the next level of oxygen-rich high-temperature environment.

[0005] Therefore, installing a gas-solid separator after the pyrolysis furnace to achieve efficient separation of pyrolysis gas and solid salt powder is a crucial step in the waste salt pyrolysis system.

[0006] Cyclone separators are widely used in the gas-solid separation process of waste salt pyrolysis systems due to their simple structure, lack of moving parts, and ability to withstand high temperatures. Their basic working principle is as follows: dust-laden gas enters the separator cylinder tangentially from the inlet, forming a high-speed rotating airflow. Solid particles are thrown against the wall under centrifugal force, spiraling down the wall and falling into the bottom dust collection hopper, while clean gas rises and exits from the central exhaust pipe.

[0007] However, the cyclone separators used in existing waste salt pyrolysis systems still have the following shortcomings in terms of separation efficiency and separation effect: First, particle deposition on the separator walls reduces the effective separation space: the flue gas temperature generated by waste salt pyrolysis typically reaches 600–800℃. Tiny salt particles carried in the flue gas adhere and deposit on the inner wall of the separator as the temperature decreases. With prolonged operation, the deposit layer on the wall gradually thickens, reducing the effective flow cross-section inside the separator, decreasing the airflow rotation speed, and consequently diminishing the centrifugal separation effect. Simultaneously, the rough surface of the deposit layer further increases the likelihood of particle capture, creating a vicious cycle that leads to a continuous decline in separation efficiency.

[0008] Secondly, coking on the inner wall leads to secondary particle entrainment: The tar components in the pyrolysis gas condense on the inner wall of the separator, forming a sticky tar layer, which traps a large amount of salt powder. When the tar layer accumulates to a certain thickness, it will peel off in sheets under the impact of high-speed airflow. These detached lumps are then re-entrained by the airflow and discharged from the exhaust pipe, causing a sharp deterioration in separation efficiency. Existing research indicates that coking in cyclone separators can reduce separation efficiency by more than 30%.

[0009] Third, short-circuit flow and secondary entrainment in the exhaust pipe inlet area: A strong airflow deflection occurs at the exhaust pipe inlet in the center of the cyclone separator. Some particles that have already separated to near the wall may be re-entrained into the exhaust pipe under the axial suction at the inlet. This short-circuit flow phenomenon is one of the core factors affecting the separation efficiency of the cyclone separator. Especially for fine particles (particle size <10μm), their small mass and weak centrifugal force make them more susceptible to being entrained and escaping by the secondary airflow.

[0010] Fourth, there is a lack of active control capability: existing cyclone separators are purely static devices, and their separation performance is entirely determined by fixed geometric parameters such as inlet velocity, cylinder diameter, and exhaust pipe insertion depth. Once manufactured, these parameters cannot be adjusted. When upstream pyrolysis conditions fluctuate (such as changes in waste salt composition leading to fluctuations in gas production or dust concentration), the separator cannot adaptively adjust to the actual conditions, resulting in unstable separation performance. Furthermore, there are no reports in the existing technology of high-temperature gas-solid separators with active flow field control capabilities for waste salt pyrolysis systems.

[0011] Fifth, the rotating airflow dissipates energy rapidly, resulting in low fine particle capture efficiency: After dust-laden gas enters the cyclone separator, the rotating airflow spirals downwards along the cylinder. Its rotational kinetic energy gradually diminishes due to wall friction and internal turbulence dissipation, significantly weakening the centrifugal separation effect in the lower part of the cylinder and the conical region. For tiny salt particles, they cannot obtain sufficient centrifugal force in the lower part of the cylinder for effective separation and ultimately escape with the airflow through the exhaust pipe. Existing research indicates that the actual separation capacity of the conical section of the cyclone separator is significantly reduced due to the decrease in the inlet rotational speed.

[0012] In summary, existing cyclone separators in waste salt pyrolysis systems generally suffer from low separation efficiency and unstable separation effects due to factors such as particle deposition on the wall surface, secondary particle entrainment caused by coking, and short-circuit flow at the exhaust pipe inlet. Furthermore, they lack active control methods to cope with fluctuations in operating conditions. There is an urgent need for a gas-solid separation device that can actively control the flow field, enhance the centrifugal separation effect, and reduce secondary particle entrainment in order to improve the efficiency of industrial waste salt treatment and purification equipment. Summary of the Invention

[0013] In view of this, the present invention provides an industrial waste salt treatment and purification device, which aims to solve the above-mentioned technical problems.

[0014] To achieve the above objectives, the present invention adopts the following technical solution: An industrial waste salt treatment and purification device includes a multi-stage pyrolysis furnace. A gas-solid separator is provided between every two adjacent pyrolysis furnaces. The gas-solid separator is used to separate the solid salt powder and high-temperature pyrolysis gas from the previous stage pyrolysis furnace, so that the separated solid salt powder is supplied to the next stage pyrolysis furnace, and the separated high-temperature pyrolysis gas is discharged as fuel. The gas-solid separator includes an upper section, a middle section, and a lower section that are connected and interconnected from top to bottom. The upper section has a separate feed pipe on its side wall, which is connected to the outlet of the pyrolysis furnace above it; the upper section has an exhaust pipe in its middle section, which extends downward into the middle section. The middle section consists of an outer cylinder and an inner cylinder rotatably disposed on the inner wall of the outer cylinder. The inner cylinder is driven to rotate by a rotation drive assembly, and the inner wall of the inner cylinder has spiral protrusions. The bottom of the lower section has a separation discharge pipe, which is connected to the feed inlet of the next-stage pyrolysis furnace.

[0015] Through the above technical solution, this invention achieves efficient separation of high-temperature pyrolysis gas and solid salt powder generated in the previous stage of pyrolysis by setting gas-solid separators between each stage of the multi-stage pyrolysis furnace. This avoids the risk of deflagration caused by the high-temperature pyrolysis gas containing combustible gases directly entering the oxygen-rich high-temperature environment of the next stage. Furthermore, the separated clean pyrolysis gas can be used as fuel to supply the burners of the next stage pyrolysis furnace, realizing the energy recovery and utilization of the pyrolysis gas. Simultaneously, the gas-solid separator, by setting a rotatable inner cylinder inside the outer cylinder, allows the gas-solid mixture to be actively driven by the rotating inner cylinder on the inner wall boundary layer, based on centrifugal separation. This effectively suppresses the attenuation of separation efficiency caused by particle deposition and eddy current dissipation on the wall surface. Moreover, the spiral protrusions on the inner wall of the inner cylinder continuously cut and disrupt the flow field structure in the exhaust pipe inlet area as the inner cylinder rotates, reducing secondary entrainment of separated particles and significantly improving the separation efficiency of the gas-solid separator under all operating conditions. This, in turn, improves the overall operational stability and resource recovery efficiency of the industrial waste salt treatment and purification device.

[0016] Preferably, in the above-mentioned industrial waste salt treatment and purification device, the upper section includes an upper shell, the separating feed pipe is tangentially connected to the upper shell, and the upper shell and the outer cylinder are fastened together by a flange structure.

[0017] Preferably, in the above-mentioned industrial waste salt treatment and purification device, the upper section further includes an upper cover, which is fastened to the top of the upper shell through a flange structure, and the exhaust pipe is fixed at the center of the upper cover.

[0018] Preferably, in the above-mentioned industrial waste salt treatment and purification device, a conical umbrella cover is fixed to the bottom of the inner wall of the exhaust pipe by multiple support rods, and an annular baffle fixed to the inner wall of the exhaust pipe is provided above the conical umbrella cover, the annular baffle corresponding to the multiple support rods.

[0019] Preferably, in the above-mentioned industrial waste salt treatment and purification device, the rotary drive assembly includes: Multiple support gears are rotatably connected to the lower part of the inner wall of the outer cylinder. The multiple support gears are arranged circumferentially. The bottom edge of the inner cylinder has a toothed ring that meshes with the multiple support gears, so that the inner cylinder is supported and positioned by the multiple support gears. A servo drive motor is installed on the outside of the outer cylinder, and the power output end of the servo drive motor is connected to a transmission shaft. The transmission shaft passes through the outer cylinder and enters the interior of the outer cylinder. A drive gear is fixed at the end of the transmission shaft. The drive gear meshes with the gear ring at the bottom of the inner cylinder to drive the inner cylinder to rotate.

[0020] Preferably, in the above-mentioned industrial waste salt treatment and purification device, an annular limiting plate is fixed on the upper part of the inner wall of the outer cylinder, the annular limiting plate is located above the inner cylinder and abuts against the top edge of the inner cylinder.

[0021] Preferably, in the above-mentioned industrial waste salt treatment and purification device, the inner cylinder has a mesh structure, and the mesh support ribs of the inner cylinder form a cutting edge on the side facing the inner wall of the outer cylinder, so that the mesh support ribs of the inner cylinder and the inner wall of the outer cylinder form a scraping structure.

[0022] Preferably, in the above-mentioned industrial waste salt treatment and purification device, the servo drive motor can drive the drive gear to rotate forward or backward, and can control the speed adjustment.

[0023] Preferably, in the above-mentioned industrial waste salt treatment and purification device, the outer cylinder has a double-layer structure, and the internal sandwich space is used to introduce a high-temperature medium, and the outer wall of the outer cylinder is covered with a heat insulation layer.

[0024] Preferably, in the above-mentioned industrial waste salt treatment and purification device, the lower section includes a lower inverted conical shell, the top of the lower inverted conical shell is fastened to the top of the outer cylinder through a flange structure, the separation discharge pipe is located at the bottom of the lower inverted conical shell, and an electromagnetic flow control valve is installed on the separation discharge pipe.

[0025] As can be seen from the above technical solution, compared with the prior art, the present invention discloses an industrial waste salt treatment and purification device, which has the following beneficial effects: 1. Enhanced safety: By installing gas-solid separators between each stage of pyrolysis furnace, the high-temperature pyrolysis gas generated in the previous stage is effectively separated from the solid salt powder, avoiding the risk of deflagration caused by pyrolysis gas containing combustible gases directly entering the next stage's oxygen-rich high-temperature environment, thus significantly improving the safety of the equipment operation.

[0026] 2. Significantly improved separation efficiency: By setting a rotatable inner cylinder inside the outer cylinder, the rotating inner cylinder actively drives the wall boundary layer, effectively suppressing the attenuation of separation efficiency caused by wall particle deposition and eddy current dissipation; the spiral protrusions on the inner wall of the inner cylinder continuously cut the flow field in the exhaust pipe inlet area as the inner cylinder rotates, reducing the secondary entrainment of separated particles and significantly improving the separation efficiency of the gas-solid separator under all operating conditions.

[0027] 3. Heat energy recovery and utilization, reducing operating costs: The separated clean pyrolysis gas is used as fuel to supply the burners of the downstream pyrolysis furnace, realizing the energy recovery and utilization of the calorific value of the pyrolysis gas, reducing the consumption of external fuel, and lowering the overall operating cost of the unit.

[0028] 4. Excellent anti-coking performance: The inner cylinder has a mesh structure, and the mesh support ribs form a cutting edge on the side facing the inner wall of the outer cylinder. When the inner cylinder rotates, it continuously scrapes off the coking material attached to the inner wall of the outer cylinder, realizing online self-cleaning. This effectively avoids the decrease in separation efficiency and equipment blockage caused by coking, and greatly extends the continuous operation cycle of the device.

[0029] 5. Strong adaptability to working conditions: The servo drive motor can drive the inner cylinder to rotate forward or backward, and can adjust the speed, so that the separator can flexibly switch between the same-direction rotation mode or the reverse rotation mode according to the upstream waste salt composition and working condition fluctuations, so as to realize the active control and adaptive operation of the separation effect.

[0030] 6. Convenient maintenance and short downtime: The inner cylinder is a replaceable structure. The entire inner cylinder can be lifted out and replaced by removing the top cover and the annular limiting plate, without disassembling the entire separator, significantly reducing maintenance time. With a spare inner cylinder, rapid rotation is possible, further reducing unplanned downtime. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0032] Figure 1 The attached figure is a schematic diagram of the industrial waste salt treatment and purification device provided by the present invention; Figure 2 The attached figure is a schematic diagram of the external structure of the gas-solid separator provided by the present invention; Figure 3 The attached figure is a cross-sectional view of the gas-solid separator provided by the present invention; Figure 4 The attached figure is a schematic diagram of a half-section of the upper section provided by the present invention; Figure 5 The attached figure is provided by the present invention. Figure 4 A magnified view of part A in the middle; Figure 6 The attached figure is a schematic diagram of a half-section of the central section provided by the present invention; Figure 7 The attached figure is a structural schematic diagram of the inner cylinder provided by the present invention; Figure 8 The attached figure is a schematic diagram of the structure of the rotary drive assembly provided by the present invention; Figure 9 The attached figure is a schematic diagram of a half-section of the lower section provided by the present invention.

[0033] in: 1-Pyrolysis furnace; 2-Gas-solid separator; 21 - Upper section; 22 - Middle section; 23 - Lower section; 24 - Rotary drive assembly; 211-Separation feed pipe; 212-Exhaust pipe; 213-Upper shell; 214-Upper cover; 215-Support rod; 216-Conical umbrella cover; 217-Annular baffle; 221-Outer cylinder; 222-Inner cylinder; 223-Spiral protrusion; 224-Gear ring; 225-Annular limiting plate; 226-Internal sandwich space; 227-Insulation layer; 231-Separation discharge pipe; 232-Lower inverted conical shell; 233-Electromagnetic flow control valve; 241-Support gear; 242-Servo drive motor; 243-Drive shaft; 244-Drive gear. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] See appendix Figure 1 This invention discloses an industrial waste salt treatment and purification device, comprising a multi-stage pyrolysis furnace 1 and a gas-solid separator 2 disposed between every two adjacent pyrolysis furnaces 1. See attached document. Figure 2 and attached Figure 3 The gas-solid separator 2 includes an upper section 21, a middle section 22, and a lower section 23 that are connected and interconnected from top to bottom.

[0036] Example 1 See appendix Figure 1 To be continued Figure 9 This embodiment provides an industrial waste salt treatment and purification device, including a three-stage pyrolysis furnace 1, namely a primary pyrolysis furnace, a secondary pyrolysis furnace, and a tertiary pyrolysis furnace. A gas-solid separator 2 is provided between the primary and secondary pyrolysis furnaces, and another gas-solid separator 2 is provided between the secondary and tertiary pyrolysis furnaces. The two gas-solid separators 2 have the same structure.

[0037] See appendix Figure 3 and attached Figure 4Taking a gas-solid separator 2 as an example, the upper section 21 includes an upper shell 213 and an upper cover 214. A separation feed pipe 211 is tangentially connected to the side wall of the upper shell 213, and the separation feed pipe 211 communicates with the outlet of the primary pyrolysis furnace. The upper cover 214 is fastened to the top of the upper shell 213 via a flange structure. An exhaust pipe 212 is fixed at the center of the upper cover 214, and the exhaust pipe 212 extends downwards along the axis of the gas-solid separator 2 into the middle section 22. See Appendix Figure 5 The bottom of the inner wall of the exhaust pipe 212 is fixed with a conical umbrella 216 by multiple support rods 215. Above the conical umbrella 216, there is an annular baffle 217 fixed to the inner wall of the exhaust pipe 212. The annular baffle 217 is correspondingly set with the multiple support rods 215.

[0038] See appendix Figure 3 and attached Figure 6 The middle section 22 includes an outer cylinder 221 and an inner cylinder 222 disposed inside the outer cylinder 221. The outer cylinder 221 has a cylindrical structure, with its upper end fastened to the upper shell 213 via a flange structure, and its lower end fastened to the lower section 23 via a flange structure. See appendix. Figure 6 The outer cylinder 221 has a double-layer structure, with a high-temperature medium (such as high-temperature flue gas from a pyrolysis furnace) introduced into the internal sandwich space 226. The outer wall of the outer cylinder 221 is covered with an insulation layer 227. See Appendix Figure 6 and attached Figure 7 The inner cylinder 222 has a mesh-like cylindrical structure and is rotatably disposed inside the outer cylinder 221. A spiral protrusion 223 is fixedly provided on the inner wall surface of the inner cylinder 222, extending spirally along the axial direction of the inner cylinder 222. A toothed ring 224 is provided at the bottom edge of the inner cylinder 222.

[0039] See appendix Figure 3 and attached Figure 8 The rotary drive assembly 24 includes multiple support gears 241, a servo drive motor 242, a transmission shaft 243, and a drive gear 244. The multiple support gears 241 are rotatably connected to the lower part of the inner wall of the outer cylinder 221 and are evenly arranged circumferentially. The gear ring 224 at the bottom of the inner cylinder 222 meshes with the multiple support gears 241 and is supported and positioned by them. The servo drive motor 242 is mounted on the outside of the outer cylinder 221, and the power output end of the servo drive motor 242 is connected to the transmission shaft 243. The transmission shaft 243 passes through the outer cylinder 221 and enters its interior. The end of the transmission shaft 243 is fixed with the drive gear 244, which meshes with the gear ring 224 at the bottom of the inner cylinder 222 to drive the inner cylinder 222 to rotate. The servo drive motor 242 can drive the drive gear 244 to rotate forward or backward, and its speed can be controlled and adjusted.

[0040] It should be noted that the servo drive motor 242 in this embodiment is mounted on an external bracket, so it is shown as suspended in the figure.

[0041] See appendix Figure 6 An annular limiting plate 225 is fixed on the upper part of the inner wall of the outer cylinder 221. The annular limiting plate 225 is located above the inner cylinder 222 and abuts against the top edge of the inner cylinder 222 to limit the axial movement of the inner cylinder 222.

[0042] See appendix Figure 3 and attached Figure 9 The lower section 23 includes a lower inverted conical shell 232, the top of which is fastened to the bottom of the outer cylinder 221 via a flange structure. The bottom of the lower inverted conical shell 232 has a separation discharge pipe 231, which communicates with the feed inlet of the next-stage pyrolysis furnace (i.e., the secondary pyrolysis furnace). An electromagnetic flow control valve 233 is installed on the separation discharge pipe 231.

[0043] The working process of the industrial waste salt treatment and purification device in this embodiment is as follows: Industrial waste salt containing organic impurities first enters the primary pyrolysis furnace, where it undergoes low-temperature pyrolysis at 250–400°C under oxygen-deficient conditions, removing low-boiling-point organic matter and moisture. The gas-solid mixture (high-temperature pyrolysis gas carrying solid salt powder) discharged from the primary pyrolysis furnace enters the gas-solid separator 2 tangentially through the separation feed pipe 211. The gas-solid mixture spirals downwards along the annular channel between the inner wall of the outer cylinder 221 and the outer wall of the inner cylinder 222. Under centrifugal force, the solid salt powder is thrown towards the inner wall of the outer cylinder 221, spirals downwards along the wall, and falls into the lower inverted conical shell 232. It is then sent to the secondary pyrolysis furnace through the separation discharge pipe 231 and the electromagnetic flow control valve 233. The clean pyrolysis gas rises from inside the inner cylinder 222 and is discharged through the exhaust pipe 212, serving as fuel in the burner of the secondary pyrolysis furnace.

[0044] See appendix Figure 7 During operation, the servo drive motor 242 drives the inner cylinder 222 to rotate at a set speed. The mesh support ribs of the inner cylinder 222 form a cutting edge on the side facing the inner wall of the outer cylinder 221, which continuously scrapes off the coking material attached to the inner wall of the outer cylinder 221 during rotation, achieving online self-cleaning.

[0045] Example 2 See appendix Figure 1 To be continued Figure 8 The difference between this embodiment and embodiment 1 is that in this embodiment, the rotation direction of the inner cylinder 222 driven by the servo drive motor 242 is the same as the rotation direction of the airflow entering the gas-solid separator 2 (co-rotation mode).

[0046] See appendix Figure 3 and attached Figure 6 In the co-rotation mode, the inner cylinder 222 rotates in the same direction as the airflow, reducing the relative velocity of the wall surface, slowing down the dissipation of kinetic energy from the airflow rotation, and enhancing the centrifugal force field across the entire height range of the separator. This embodiment is suitable for situations where the upstream waste salt contains a high proportion of fine particles (particle size <10μm). Taking sodium chloride waste salt from a chemical plant as an example, the proportion of fine particles in the waste salt is approximately 35%, and the inlet velocity of the pyrolysis gas entering the separator is 18–22 m / s. By controlling the rotational speed of the inner cylinder 222 to 120–180 r / min and operating in the same direction, the separator's collection efficiency for fine particles <10μm is improved by approximately 25%–35% compared to traditional static cyclone separators, and the overall separation efficiency can reach over 96%.

[0047] See appendix Figure 4 and attached Figure 5 When the separated clean pyrolysis gas is discharged through the exhaust pipe 212, the conical umbrella 216 and the annular baffle 217 at the inlet of the exhaust pipe 212 work together: the conical umbrella 216 guides the airflow to change direction, and the annular baffle 217 prevents the separated particles from being re-entrained by the axial suction airflow, further reducing secondary entrainment.

[0048] Example 3 See appendix Figure 1 To be continued Figure 8 The difference between this embodiment and embodiment 1 is that in this embodiment, the rotation direction of the inner cylinder 222 driven by the servo drive motor 242 is opposite to the rotation direction of the airflow entering the gas-solid separator 2 (reverse rotation mode).

[0049] See appendix Figure 3 and attached Figure 6 In the reverse rotation mode, the rotation direction of the inner cylinder 222 is opposite to the airflow direction, increasing the wall shear force and promoting the forced stripping and axial transport of deposited particles. Simultaneously, the axial suction flow in the inlet area of ​​the exhaust pipe 212 is disrupted, reducing secondary entrainment. This embodiment is suitable for situations where the upstream waste salt has a high proportion of coarse particles or severe wall deposition. Taking waste salt from a pesticide production enterprise as an example, the waste salt has a high tar content, and significant coking occurs after 4-6 hours of operation in a traditional cyclone separator. The rotation speed of the inner cylinder 222 is controlled at 80-120 r / min, operating in reverse rotation (see attached diagram). Figure 7 The mesh support ribs of the inner cylinder 222 continuously scrape away the coking material on the inner wall of the outer cylinder 221. The separator can run continuously for 240 hours without stopping for cleaning, and the overall separation efficiency remains above 92%.

[0050] The separated pyrolysis gas is discharged through exhaust pipe 212 and fed into the burner of the three-stage pyrolysis furnace as fuel, realizing the energy utilization of the pyrolysis gas.

[0051] Example 4 See appendix Figure 1 To be continued Figure 8 The difference between this embodiment and embodiment 1 is that in this embodiment, the servo drive motor 242 is a variable frequency speed control motor, which can automatically adjust the speed and rotation direction of the inner cylinder 222 according to the pressure difference signal between the inlet and outlet of the gas-solid separator 2.

[0052] When an increase in the pressure difference between the inlet and outlet of the gas-solid separator 2 is detected (indicating increased wall deposition or coking), the control system controls the servo drive motor 242 to switch to reverse rotation mode and increase its speed. The scraping action of the mesh support ribs removes deposits from the inner wall of the outer cylinder 221. Once the pressure difference returns to normal, the control system automatically switches back to co-rotation mode based on upstream conditions to maintain high separation efficiency. This embodiment achieves adaptive operation of the separator and is suitable for conditions with large fluctuations in waste salt composition.

[0053] Example 5 See appendix Figure 6 The difference between this embodiment and Embodiment 1 is that in this embodiment, the high-temperature medium introduced into the internal sandwich space 226 of the outer cylinder 221 is high-temperature flue gas from the pyrolysis furnace, and the temperature of the high-temperature medium is 400-600℃. Through the heating of the insulation jacket, the temperature of the inner wall of the outer cylinder 221 is maintained above 350℃, effectively preventing the tar components in the pyrolysis gas from condensing and adhering due to temperature reduction. The insulation layer 227 of the outer wall of the outer cylinder 221 is an aluminum silicate fiber felt insulation layer with a thickness of 50-100mm, further reducing heat loss.

[0054] Example 6 See appendix Figure 7 The difference between this embodiment and Embodiment 1 is that in this embodiment, the inner cylinder 222 is a mesh cylinder woven from 310S heat-resistant stainless steel wire, with a mesh size of 3mm × 3mm and an opening rate of 65%. The mesh structure reduces the weight of the inner cylinder 222 by approximately 60% compared to a solid cylinder of the same size, thereby reducing the driving load and energy consumption of the rotary drive assembly 24. Simultaneously, the mesh structure allows for partial gas flow, reducing airflow resistance during the rotation of the inner cylinder 222 and lowering the system pressure drop.

[0055] Example 7 See appendix Figure 3 and attached Figure 6 The difference between this embodiment and embodiment 1 is that in this embodiment, the inner cylinder 222 of the gas-solid separator 2 is a replaceable structure.

[0056] Specifically, see Appendix Figure 4 The upper cover 214 of the upper section 21 is fastened to the upper shell 213 via a flange structure. During normal operation, the upper cover 214 and the upper shell 213 remain sealed and fixed, and the exhaust pipe 212 fixed at the center of the upper cover 214 extends into the inner cylinder 222. (See appendix) Figure 6 The annular limiting plate 225 is fixed to the upper part of the inner wall of the outer cylinder 221, located above the inner cylinder 222, and abuts against the top edge of the inner cylinder 222 to limit the axial movement of the inner cylinder 222 during operation.

[0057] When the inner cylinder 222 needs to be replaced due to wear, deformation, or severe coking from long-term operation, first remove the flange fasteners at the connection between the upper cover 214 and the upper shell 213. (See Appendix) Figure 4 Lift and remove the upper cover 214 along with the exhaust pipe 212. Then remove the fasteners between the annular limiting plate 225 and the inner wall of the outer cylinder 221. See attached document. Figure 6 Remove the annular limiting plate 225 from inside the outer cylinder 221. At this time, there is no limiting structure above the inner cylinder 222. (See attached diagram) Figure 3 and attached Figure 6 The inner cylinder 222 is lifted out entirely from the top of the outer cylinder 221 using hoisting equipment. After the new inner cylinder 222 is hoisted into place from the top of the outer cylinder 221, the annular limiting plate 225 and the upper cover 214 are reinstalled, thus completing the replacement operation.

[0058] With the above structure, it is not necessary to disassemble the entire gas-solid separator 2 from the pipeline, nor is it necessary to remove the flange between the outer cylinder 221 and the upper shell 213 or the lower section 23. Only the upper cover 214 and the annular limiting plate 225 need to be removed to quickly replace the inner cylinder 222. The entire replacement operation takes no more than 2 hours, which significantly shortens the maintenance time compared to the traditional cyclone separator that requires complete disassembly and cleaning.

[0059] Furthermore, this embodiment can also be configured with at least one set of spare inner cylinder 222. When the operating inner cylinder 222 needs to be replaced, production can be resumed simply by installing the spare inner cylinder 222. The removed inner cylinder 222 can be cleaned and repaired offline and used as a spare part for the next cycle. By rotating the use of the spare inner cylinder 222, the continuous operating time of the device is significantly extended.

[0060] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0061] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An industrial waste salt treatment and purification device, characterized in that, The system includes a multi-stage pyrolysis furnace (1), with a gas-solid separator (2) between each pair of adjacent pyrolysis furnaces (1). The gas-solid separator (2) is used to separate the solid salt powder and high-temperature pyrolysis gas from the previous stage pyrolysis furnace (1), so that the separated solid salt powder is supplied to the next stage pyrolysis furnace (1), and the separated high-temperature pyrolysis gas is discharged as fuel. The gas-solid separator (2) includes an upper section (21), a middle section (22), and a lower section (23) that are connected and interconnected from top to bottom. The upper section (21) has a separating feed pipe (211) on its side wall, which is connected to the discharge port of the pyrolysis furnace (1) above it; the upper section (21) has an exhaust pipe (212) in its middle section, which extends downward into the middle section (22); The middle section (22) consists of an outer cylinder (221) and an inner cylinder (222) rotatably disposed on the inner wall of the outer cylinder (221). The inner cylinder (222) is driven to rotate by a rotation drive assembly (24), and the inner wall of the inner cylinder (222) has a spiral protrusion (223). The bottom of the lower section (23) has a separation discharge pipe (231) which is connected to the feed inlet of the next-level pyrolysis furnace (1).

2. The industrial waste salt treatment and purification device according to claim 1, characterized in that, The upper section (21) includes an upper shell (213), the separating feed pipe (211) is tangentially connected to the upper shell (213), and the upper shell (213) is fastened to the outer cylinder (221) through a flange structure.

3. The industrial waste salt treatment and purification device according to claim 2, characterized in that, The upper section (21) also includes an upper cover (214), which is fastened to the top of the upper housing (213) by a flange structure, and the exhaust pipe (212) is fixed at the center of the upper cover (214).

4. The industrial waste salt treatment and purification device according to claim 3, characterized in that, The bottom of the inner wall of the exhaust pipe (212) is fixed with a conical umbrella (216) by multiple support rods (215). Above the conical umbrella (216) is an annular baffle (217) fixed to the inner wall of the exhaust pipe (212). The annular baffle (217) corresponds to the multiple support rods (215).

5. An industrial waste salt treatment and purification device according to any one of claims 1-4, characterized in that, The rotary drive assembly (24) includes: Multiple support gears (241) are rotatably connected to the lower part of the inner wall of the outer cylinder (221). The multiple support gears (241) are arranged circumferentially. The bottom edge of the inner cylinder (222) has a gear ring (224) that meshes with the multiple support gears (241), so that the inner cylinder (222) is supported and positioned by the multiple support gears (241). A servo drive motor (242) is installed on the outside of the outer cylinder (221), and the power output end of the servo drive motor (242) is connected to a transmission shaft (243). The transmission shaft (243) passes through the outer cylinder (221) and enters the interior of the outer cylinder (221). A drive gear (244) is fixed at the end of the transmission shaft (243). The drive gear (244) meshes with the gear ring (224) at the bottom of the inner cylinder (222) to drive the inner cylinder (222) to rotate.

6. The industrial waste salt treatment and purification device according to claim 5, characterized in that, An annular limiting plate (225) is fixed on the upper part of the inner wall of the outer cylinder (221). The annular limiting plate (225) is located above the inner cylinder (222) and abuts against the top edge of the inner cylinder (222).

7. The industrial waste salt treatment and purification device according to claim 5, characterized in that, The inner cylinder (222) has a mesh structure. The mesh support ribs of the inner cylinder (222) form a cutting edge on the side facing the inner wall of the outer cylinder (221), so that the mesh support ribs of the inner cylinder (222) and the inner wall of the outer cylinder (221) form a scraping structure.

8. The industrial waste salt treatment and purification device according to claim 5, characterized in that, The servo drive motor (242) can drive the drive gear (244) to rotate forward or backward, and can control the speed adjustment.

9. The industrial waste salt treatment and purification device according to claim 1, characterized in that, The outer cylinder (221) has a double-layer structure, and the internal sandwich space (226) is used to introduce a high-temperature medium. The outer wall of the outer cylinder (221) is covered with a heat insulation layer (227).

10. An industrial waste salt treatment and purification device according to claim 1, characterized in that, The lower section (23) includes a lower inverted conical shell (232), the top of which is fastened to the top of the outer cylinder (221) by a flange structure. The separation discharge pipe (231) is located at the bottom of the lower inverted conical shell (232), and an electromagnetic flow control valve (233) is installed on the separation discharge pipe (231).

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