Evaporative crystallization device for fluorine-containing high-salt wastewater and process thereof

Abstract

The application provides an evaporation crystallization device for fluorine-containing high-salinity wastewater and a process thereof, and relates to the technical field of high-salinity wastewater treatment. The evaporation crystallization device for fluorine-containing high-salinity wastewater comprises a support and an evaporation tank. A first material port for connecting a material stacking ring cavity and a material storage cavity is arranged on an inner cylinder. A second material port for connecting the material storage cavity and a material discharging cavity is arranged on a first baffle. A heating assembly contacts and heats the wastewater, so that the wastewater solvent is evaporated and discharged, and the wastewater solute gradually separates out to form crystals and moves to the material stacking ring cavity. The first material port is opened, and the second material port is closed. The crystals in the material stacking ring cavity enter the material storage cavity through the first material port. Then, the first material port is closed, and the second material port is opened. The crystals in the material storage cavity enter the material discharging cavity through the second material port. The crystals in the material discharging cavity are discharged through a first auger. The crystals separated out can be continuously discharged without stopping the machine, the negative pressure environment in the evaporation tank is avoided from being damaged, and the working efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-salt wastewater treatment, in particular to an evaporation and crystallization device for fluorine-containing high-salt wastewater and a process thereof. Background Art

[0002] With the acceleration of industrialization, the discharge problem of high-salt wastewater is becoming increasingly serious. The treatment of fluorine-containing high-salt wastewater is a common problem faced by the chemical, electronic, photovoltaic and other industries. This type of wastewater also contains high concentrations of soluble salts, fluoride ions, organic matter and heavy metals. Its sources are wide and the output is increasing year by year. It is mainly manifested in high salt concentration, high osmotic pressure, and dehydration of microbial cells causing cell protoplasm separation. If this type of wastewater is directly discharged into the environment, it will cause great harm to environmental organisms. In the existing technology, the evaporation crystallization process is widely used in the treatment of high-salt wastewater because it can effectively separate water and solutes in wastewater, so as to achieve the recovery of water resources and salts and reduce the impact on the environment. This process causes the solution containing non-volatile solutes to boil and evaporate, and the original unsaturated solution gradually becomes a saturated solution and a supersaturated solution until the solute precipitates in the form of crystals.

[0003] Existing evaporation crystallization devices often reduce the evaporation chamber pressure to a negative value to lower the boiling point and thereby improve evaporation crystallization efficiency. However, this requires shutting down the device to discharge the precipitated crystals, disrupting the negative pressure environment within the evaporation chamber. This prevents continuous crystallization discharge and reduces efficiency.

[0004] The information disclosed in the background technology section of the present invention is only intended to deepen the understanding of the general background technology of the present invention, and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. Summary of the Invention

[0005] Based on this, it is necessary to provide an evaporation and crystallization device for fluorine-containing high-salt wastewater and a process thereof in response to the problems existing in the current evaporation and crystallization device for high-salt wastewater.

[0006] The above purpose is achieved through the following technical solutions:

[0007] An evaporation and crystallization device for fluorine-containing high-salt wastewater comprises a bracket and a cylindrical evaporation tank arranged on the bracket, wherein the evaporation tank is in a negative pressure environment and contains wastewater, a pile annular cavity is formed in the evaporation tank, and crystals precipitated in the evaporation tank have a tendency to move toward the pile annular cavity, heating components in contact with the wastewater are provided on both sides of the pile annular cavity, a collecting pipe is provided on the evaporation tank and connected to the interior thereof, and is used to collect evaporated wastewater solvent; an inner cylinder coaxial with the evaporation tank is fixed in the evaporation tank, a first baffle is provided in the inner cylinder, and the first baffle separates the inner cavity of the inner cylinder into a storage cavity and a discharge cavity, and a pipe for connecting the inner cylinder to the discharge cavity is provided on the inner cylinder. A first material port is provided to connect the stacking ring cavity and the storage cavity, a second material port is provided on the first baffle to connect the storage cavity and the discharge cavity, and a first auger for discharging is provided in the discharge cavity; the first material port and the second material port are both capable of switching between open and closed states, and at the same time, one of the first material port and the second material port is in an open state, when the first material port is opened and the second material port is closed, the crystals in the stacking ring cavity enter the storage cavity through the first material port, and when the first material port is closed and the second material port is opened, the crystals in the storage cavity enter the discharge cavity through the second material port.

[0008] Furthermore, the first material port is opened on the side wall of the inner cylinder, the outer cylinder is rotatably sleeved on the outer side of the inner cylinder, and a third material port is opened on the side wall of the outer cylinder. When the outer cylinder rotates until the third material port coincides with the first material port, the first material port is opened, and when the outer cylinder rotates until the third material port is offset from the first material port, the first material port is closed; a second baffle is rotatably provided on the first baffle, and a fourth material port is opened on the second baffle. The outer cylinder can drive the second baffle to rotate, and when the fourth material port coincides with the second material port, the second material port is opened, and when the fourth material port is offset from the second material port, the second material port is closed.

[0009] Furthermore, an inner gear ring coaxial with the outer cylinder is provided on the inner wall of the outer cylinder, an outer gear ring is provided on the outer surface of the second baffle, and a gear that meshes with both the inner gear ring and the outer gear ring is rotatably provided on the first baffle.

[0010] Furthermore, a scraper is provided on the outer cylinder along its radial direction, and the scraper is located at the edge of the third material port. When the first material port is opened and the second material port is closed, the scraper is used to send the crystals in the stacking ring cavity into the storage cavity through the first material port.

[0011] Furthermore, the heating assembly rotates synchronously with the outer cylinder, and the heating assembly includes a plurality of heating tubes arranged in sequence along a preset trajectory, the preset trajectory is a vortex line, and connecting pieces are provided between adjacent heating tubes to connect the adjacent heating tubes.

[0012] Furthermore, the preset trajectories of the two heating components rotate in opposite directions.

[0013] Furthermore, the spacing between adjacent heating tubes is positively correlated with a first distance, and the first distance is the spacing between the heating tube and the outer tube.

[0014] Furthermore, a high-temperature medium flows in the heating assembly, and the heating assembly also includes two ring bodies sleeved on the outer cylinder, the two ring bodies are respectively arranged at the two ends of the heating tube, and the interior of the ring bodies is connected to the interior of the heating tube; the ring body includes a first half shell and a second half shell that are sealed for relative rotation, the first half shell is stationary relative to the evaporator, one of the first half shells is provided with an inlet pipe, the inlet pipe is used to provide high-temperature medium to the heating assembly, and the other first half shell is provided with an outlet pipe, the outlet pipe is used to outlet the high-temperature medium in the heating assembly; the second half shell rotates synchronously with the outer cylinder, and the two second half shells are respectively fixed to the two ends of the heating tube.

[0015] Furthermore, a second auger is rotatably provided between the two second half shells. When the second auger rotates, it scrapes off the crystals attached to the inner wall of the evaporation tank and transports the scraped crystals to the stacking annular cavity.

[0016] In addition, the present invention also provides the following technical solutions:

[0017] An evaporation and crystallization process for fluorine-containing high-salt wastewater comprises the following steps:

[0018] The wastewater is passed into the evaporation tank, and the negative pressure environment in the evaporation tank is maintained. The heating component is started to heat the wastewater. The wastewater solvent gradually evaporates and is collected through the collection pipe. The wastewater solute gradually precipitates and moves to the pile ring cavity;

[0019] The first material port is controlled to open and the second material port is controlled to close, and the crystals in the stacking annular cavity enter the storage cavity through the first material port;

[0020] The first material port is controlled to be closed and the second material port is opened. The crystals in the storage chamber enter the discharge chamber through the second material port. The first auger is started to discharge the crystals in the discharge chamber.

[0021] The beneficial effects of the present invention are as follows: the present invention contacts and heats the wastewater through the heating component, so that the wastewater solvent evaporates and is discharged, and the wastewater solute gradually precipitates to form crystals and moves toward the stacking ring cavity, controls the first material port to be opened and the second material port to be closed, and the crystals in the stacking ring cavity enter the storage cavity through the first material port, and then controls the first material port to be closed and the second material port to be opened, and the crystals in the storage cavity enter the discharge cavity through the second material port, and the crystals in the discharge cavity are discharged through the first auger, thereby realizing continuous discharge of the precipitated crystals without stopping the machine, while avoiding destroying the negative pressure environment in the evaporation tank, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic structural diagram of an evaporation and crystallization device for fluorine-containing high-salt wastewater provided in an embodiment of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the structure of the middle evaporation tank;

[0024] Figure 3 for Figure 2 Side view of;

[0025] Figure 4 for Figure 3 AA-direction cross-sectional view;

[0026] Figure 5 for Figure 2 Schematic diagram of the internal structure of the evaporation tank;

[0027] Figure 6 for Figure 5 Exploded view of parts;

[0028] Figure 7 for Figure 6 Exploded view of parts of local structure;

[0029] Figure 8 for Figure 7 A partial enlarged view of point B in the middle;

[0030] Figure 9 for Figure 5 Front view of

[0031] Figure 10 for Figure 9 The cross-sectional view along CC direction;

[0032] Figure 11 for Figure 9 DD-direction cross-sectional view.

[0033] in:

[0034] 100, bracket; 101, evaporation tank; 102, heat exchanger; 103, vacuum pump; 104, wastewater inlet; 105, first motor; 106, second motor;

[0035] 201, stacking ring cavity; 202, inner cylinder; 203, first baffle; 204, storage cavity; 205, discharge cavity; 206, first feed port; 207, second feed port; 208, first auger; 209, outer cylinder; 210, third feed port; 211, second baffle; 212, fourth feed port; 213, inner gear ring; 214, outer gear ring; 215, gear; 216, connecting cylinder; 217, scraper screen; 218, enclosure;

[0036] 300, heating assembly; 301, heating tube; 302, connecting piece; 303, ring body; 304, first half shell; 305, second half shell; 306, inlet tube; 307, outlet tube; 308, second auger. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0038] The serial numbers assigned to components herein, such as "first," "second," etc., are used solely to distinguish the objects being described and do not convey any sequential or technical meaning. References to "connection" and "coupling" herein, unless otherwise specified, include both direct and indirect connections (couplings). In the description of the present invention, it should be understood that terms such as "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the device or component being referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0039] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0040] like Figures 1 to 11 As shown, an embodiment of the present invention provides an evaporation and crystallization device for fluorine-containing high-salt wastewater, comprising a bracket 100 and a cylindrical evaporation tank 101 arranged on the bracket 100. The evaporation tank 101 is in a negative pressure environment and contains wastewater. A stacking ring cavity 201 is formed in the evaporation tank 101. Crystals precipitated in the evaporation tank 101 have a tendency to move toward the stacking ring cavity 201. Both sides of the stacking ring cavity 201 are provided with heating components 300 in contact with the wastewater. The evaporation tank 101 is provided with a collecting pipe connected to the interior thereof for collecting evaporated wastewater solvent; an inner cylinder 202 coaxial with the evaporation tank 101 is fixed therein, and a first baffle 203 is provided in the inner cylinder 202. The first baffle 203 divides the inner cavity of the inner cylinder 202 into a storage cavity 204 and a discharge cavity 205. The inner cylinder 20 2 is provided with a first material port 206 for connecting the stacking annular cavity 201 and the storage cavity 204, and a second material port 207 is provided on the first baffle 203 for connecting the storage cavity 204 and the discharge cavity 205. A first auger 208 for discharging is provided in the discharge cavity 205; the first material port 206 and the second material port 207 are both switchable between open and closed states, and at the same time, one of the first material port 206 and the second material port 207 is in the open state. When the first material port 206 is opened and the second material port 207 is closed, the crystals in the stacking annular cavity 201 enter the storage cavity 204 through the first material port 206; when the first material port 206 is closed and the second material port 207 is opened, the crystals in the storage cavity 204 enter the discharge cavity 205 through the second material port 207.

[0041] The heating component 300 contacts and heats the wastewater, causing the wastewater solvent to evaporate and be discharged, while the wastewater solute gradually precipitates to form crystals and moves toward the stacking annular cavity 201. The first material port 206 is controlled to be open and the second material port 207 is controlled to be closed. The crystals in the stacking annular cavity 201 enter the storage cavity 204 through the first material port 206. The first material port 206 is then controlled to be closed and the second material port 207 is controlled to be open. The crystals in the storage cavity 204 enter the discharge cavity 205 through the second material port 207 and are discharged from the discharge cavity 205 by the first auger 208. In this way, the precipitated crystals can be continuously discharged without stopping the machine, while avoiding damaging the negative pressure environment in the evaporation tank 101, thereby improving work efficiency.

[0042] The support 100 is provided with a heat exchanger 102, and a collection pipe directs the evaporated wastewater solvent into the heat exchanger 102 for condensation. The support 100 is also provided with a vacuum pump 103 connected to the evaporator 101, which is used to maintain a negative pressure in the evaporator 101. By reducing the pressure in the evaporator 101 to a negative value, the boiling point can be lowered, thereby improving the evaporation efficiency. The evaporator 101 is fixed to the support 100, and a wastewater inlet 104 is opened on one side of the evaporator 101. The height of the wastewater entering the evaporator 101 should be lower than the height of the first material port 206 to prevent the wastewater from directly entering the storage chamber 204 through the first material port 206. The stacking ring cavity 201 is formed in the middle of the evaporator 101, and the diameter of the stacking ring cavity 201 is larger than the inner diameter of the evaporator 101, so that crystals can be accumulated in the stacking ring cavity 201, which is convenient for subsequent centralized cleaning and discharge. A first motor 105 is installed on one side of the evaporator 101, along with a corresponding power supply and controller for start and stop control. The output end of the first motor 105 extends into the inner drum 202 and drives the first auger 208 to rotate. One end of the inner drum 202 is rotatably connected to the output end of the first motor 105. The other end of the inner drum 202 is open, through which the first auger 208 discharges the crystals. Furthermore, the portions of the first auger 208 located within the storage chamber 204 and the discharge chamber 205 both have blades, which are blocked by a first baffle 203. Therefore, within the storage chamber 204, the first auger 208 transports the crystals through the second inlet 207 to the discharge chamber 205. Within the discharge chamber 205, the first auger 208 also transports and discharges the crystals.

[0043] In one embodiment, the first material port 206 is provided on the side wall of the inner cylinder 202, and the outer cylinder 209 is rotatably sleeved on the outer side of the inner cylinder 202, and a third material port 210 is provided on the side wall of the outer cylinder 209. When the outer cylinder 209 rotates to the point where the third material port 210 coincides with the first material port 206, the first material port 206 is opened, and when the outer cylinder 209 rotates to the point where the third material port 210 is offset from the first material port 206, the first material port 206 is closed; a second baffle 211 is rotatably provided on the first baffle 203, and a fourth material port 212 is provided on the second baffle 211. The outer cylinder 209 can drive the second baffle 211 to rotate, and when the fourth material port 212 coincides with the second material port 207, the second material port 207 is opened, and when the fourth material port 212 is offset from the second material port 207, the second material port 207 is closed.

[0044] The outer cylinder 209 rotates to switch the third material port 210 between overlapping and staggered with the first material port 206, so that the first material port 206 switches between open and closed; the second baffle 211 rotates to switch the fourth material port 212 between overlapping and staggered with the second material port 207, so that the second material port 207 switches between open and closed.

[0045] Among them, when the third material port 210 is staggered with the first material port 206, the wall of the outer tube 209 blocks the first material port 206 and the first material port 206 is in a closed state; when the fourth material port 212 is staggered with the first material port 206, the second baffle 211 blocks the second material port 207 and the second material port 207 is in a closed state.

[0046] A second motor 106 is provided on one side of the evaporator 101 and is equipped with a corresponding power supply and controller to control start and stop. The output end of the second motor 106 is used to drive the outer cylinder 209 to rotate. The inner and outer sides of the outer cylinder 209 are respectively connected to the inner cylinder 202 and the evaporator 101 through bearings and sealing rings to achieve rotational sealing.

[0047] The size of the first opening 206 is equal to that of the third opening 210, and the size of the second opening 207 is equal to that of the fourth opening 212. The first opening 206 extends along the circumference of the inner cylinder 202, while the third opening 210 extends along the circumference of the outer cylinder 209. The first and third openings 206, 210 are opened at the same angle. The second and fourth openings 207, 212 are both fan-shaped, with the center of the fan located on the axis of the inner cylinder 202 or outer cylinder 209. Of course, the first, second, third, and fourth openings 206, 207, 210, and 212 may also have other corresponding shapes. Of course, the sizes of the first and third openings 206, 210, and the sizes of the second and fourth openings 207, 212 may also differ. However, as long as there is some overlap, the first and second openings 206, 207, 207 have a certain open area, i.e., they are in an open state.

[0048] In one embodiment, see Figure 8 An inner ring gear 213 coaxial with the outer cylinder 209 is provided on the inner wall thereof, an outer ring gear 214 is provided on the outer surface of the second baffle 211, and a gear 215 rotatably provided on the first baffle 203 that meshes with both the inner ring gear 213 and the outer ring gear 214.

[0049] The outer cylinder 209 and the inner ring gear 213 rotate, and the gear 215 engages with the inner ring gear 213 and the outer ring gear 214 at the same time, driving the second baffle 211 to rotate, so that the outer cylinder 209 drives the second baffle 211 to rotate. While the first material port 206 switches between opening and closing, the second material port 207 also switches between opening and closing.

[0050] The modules and pressure angles of the inner ring gear 213, gear 215, and outer ring gear 214 are equal to ensure intermeshing. Furthermore, the number of teeth and transmission ratios of the three should satisfy the following relationship: when the third inlet 210 overlaps with the first inlet 206, the fourth inlet 212 is offset from the second inlet 207; when the third inlet 210 is offset from the first inlet 206, the fourth inlet 212 overlaps with the second inlet 207. That is, when the first inlet 206 is open, the second inlet 207 is closed; and when the first inlet 206 is closed, the second inlet 207 is open. Furthermore, multiple gears 215 can be arranged at equal intervals along the circumference of the inner cylinder 202 to enhance transmission stability among the inner ring gear 213, gear 215, and outer ring gear 214. It is worth noting that the first inlet 206 and the second inlet 207 cannot be simultaneously open, but can be simultaneously closed.

[0051] To facilitate assembly, the outer cylinder 209 is divided into two sections along its axial direction. The inner gear ring 213 is located on one of the sections. A connecting cylinder 216 is sleeved onto the adjacent ends of the two outer cylinder sections 209. The connecting cylinder 216 and the outer cylinder 209 are secured by screws or rivets and provided with a sealing ring to maintain a seal. Therefore, the connecting cylinder 216 can be considered a part of the outer cylinder 209, and the third inlet 210 is located on the connecting cylinder 216.

[0052] In one embodiment, a scraper 217 is provided on the outer cylinder 209 along its radial direction. The scraper 217 is located at the edge of the third material port 210. When the first material port 206 is opened and the second material port 207 is closed, the scraper 217 is used to deliver the crystals in the stacking ring cavity 201 into the storage cavity 204 through the first material port 206.

[0053] The scraper 217 has a small mesh size, which allows the crystals to be retained on the scraper 217 while filtering out water. The scraper 217 is also equipped with a barrier 218 on the edges of three sides, except for one side near the outer cylinder 209, to increase the retention rate of the crystals. The scraper 217 is mounted on the connecting cylinder 216. Crystals precipitated in wastewater generally exist below the liquid surface. When the scraper 217 rotates below the liquid surface, the crystals are retained. The scraper 217 continues to rotate to deliver the crystals into the storage chamber 204.

[0054] In one embodiment, the heating assembly 300 rotates synchronously with the outer cylinder 209. The heating assembly 300 includes a plurality of heating tubes 301 arranged in sequence along a preset trajectory. The preset trajectory is a spiral line. Connectors 302 are provided between adjacent heating tubes 301 to connect adjacent heating tubes 301.

[0055] The wastewater is heated by the heating tubes 301 . The heating tubes 301 are arranged in sequence along the trajectory of the spiral line and rotate synchronously with the outer cylinder 209 . This has a dual stirring effect on the wastewater along the radial and axial directions of the evaporation tank 101 , ensuring full contact between the heating tubes 301 and the wastewater, thereby improving heat exchange efficiency.

[0056] Since the heating tubes 301 are arranged in sequence along the trajectory of the spiral line, the heating tubes 301 and the connecting member 302 can be regarded as a spiral plate. When the spiral plate rotates, it can push the wastewater and crystals from the center to the edge along the radial direction of the evaporation tank 101. At the same time, when the spiral plate rotates, in the side view of the evaporation tank 101, as shown in FIG. Figure 10 、 Figure 11 The wastewater and crystals flow from the inside to the outside of the spiral plate, or from the outside to the inside of the spiral plate, and flow in both directions along the axial direction of the evaporator 101. Since one side of the spiral plate is the end wall of the evaporator 101, the wastewater and crystals can only flow into the other side of the spiral plate, that is, into the material stacking annular cavity 201 at the center of the evaporator 101, thereby achieving a dual stirring effect on the wastewater along the radial and axial directions of the evaporator 101.

[0057] In one embodiment, the preset trajectories of the two heating elements 300 have opposite rotation directions.

[0058] The outer cylinder 209 drives the two heating components 300 to rotate in the same direction. The spiral lines corresponding to the two heating components 300 rotate in opposite directions. The heating tube 301 and the connecting piece 302 are still regarded as a spiral plate. Figure 10 The vortex plate in the middle rotates counterclockwise, Figure 11 The vortex plate in the vortex rotates clockwise. Figure 10 For the heating assembly 300 in the spiral plate, when the spiral plate rotates counterclockwise, the wastewater and crystals flow from the inside of the spiral plate to the outside, and flow to the other side of the spiral plate, that is, the stacking annular cavity 201 in the center of the evaporation tank 101; and for Figure 11 For example, when the spiral plate rotates clockwise, the wastewater and crystals flow from the outside of the spiral plate to the inside, and then flow to the other side of the spiral plate, that is, the material storage annular cavity 201 in the center of the evaporation tank 101. Therefore, both heating assemblies 300 have the function of transporting wastewater and crystals to the material storage annular cavity 201, but Figure 10 The heating component 300 in the spiral plate transports the wastewater and crystals outside the spiral plate to the pile ring cavity 201. Figure 11The heating assembly 300 in the spiral plate transports the wastewater and crystals inside the spiral plate to the stockpiling annular cavity 201. This avoids the following situation: when the spiral lines corresponding to the two heating assemblies 300 have the same rotation direction, the two heating assemblies 300 simultaneously transport the wastewater and crystals outside the spiral plate to the stockpiling annular cavity 201, or simultaneously transport the wastewater and crystals inside the spiral plate to the stockpiling annular cavity 201, causing wastewater and crystal flow impact and affecting the operating stability of other components.

[0059] In one embodiment, the distance between adjacent heating tubes 301 is positively correlated with the first distance, which is the distance between the heating tubes 301 and the outer tube 209 .

[0060] Multiple heating tubes 301 rotate synchronously with the outer tube, and the central angle of each heating tube 301 rotated in the same time is the same, but the wastewater closer to the outer tube 209 is less, so the spacing between the heating tubes 301 closer to the outer tube 209 is set to be larger, and the wastewater farther away from the outer tube 209 is more, so the spacing between the heating tubes 301 farther away from the outer tube 209 is set to be smaller, thereby achieving uniform heating of the wastewater close to or far away from the outer tube 209, avoiding the following situation: when the spacing between adjacent heating tubes 301 is the same, the wastewater close to the outer tube 209 is overheated or the wastewater far away from the outer tube 209 is underheated.

[0061] In one embodiment, see Figures 5 to 7 A high-temperature medium flows through the heating assembly 300. The heating assembly 300 further includes two ring bodies 303 sleeved on the outer cylinder 209. The two ring bodies 303 are respectively arranged at both ends of the heating tube 301, and the interior of the ring bodies 303 is connected to the interior of the heating tube 301. The ring body 303 includes a first half shell 304 and a second half shell 305 that are sealed for relative rotation. The first half shell 304 is stationary relative to the evaporator 101. One of the first half shells 304 is provided with an inlet pipe 306 for supplying high-temperature medium to the heating assembly 300. The other first half shell 304 is provided with an outlet pipe 307 for discharging the high-temperature medium in the heating assembly 300. The second half shell 305 rotates synchronously with the outer cylinder 209. The two second half shells 305 are respectively fixed to the two ends of the heating tube 301.

[0062] The outer cylinder 209 drives the multiple heating tubes 301 to rotate together through the two second half shells 305 to stir the wastewater. Simultaneously, the two first half shells 304 are provided with an inlet pipe 306 and an outlet pipe 307 for inputting and outputting high-temperature medium, thereby ensuring the circulation of high-temperature medium throughout the heating assembly 300.

[0063] The ring body 303 is divided into a first half shell 304 and a second half shell 305 along a plane perpendicular to its axis. The diameter of the ring body 303 near the center of the evaporator 101 is smaller than the diameter of the ring body 303 farther from the center. The reverse is also possible, or the diameters of the two ring bodies 303 remain the same. Furthermore, the high-temperature medium is high-temperature steam. The bracket 100 is provided with a steam supply device. The inlet pipe 306 extends through the evaporator 101 and is connected to the output end of the steam supply device to provide high-temperature steam to the heating assembly 300. The outlet pipe 307 extends through the evaporator 101 and is connected to the heat exchanger 102 to direct the high-temperature medium within the heating assembly 300 into the heat exchanger 102 for condensation.

[0064] In one embodiment, a second auger 308 is rotatably provided between the two second half shells 305 . The second auger 308 scrapes off the crystals attached to the inner wall of the evaporation tank 101 when rotating, and transports the scraped crystals to the stacking annular cavity 201 .

[0065] When crystals adhere to the inner wall of the evaporator 101 and are not cleaned promptly, the residual moisture within the crystals is difficult to evaporate quickly, requiring subsequent continuous heating, which affects the efficiency of salt crystallization. Therefore, the outer cylinder 209 drives the multiple heating tubes 301 to rotate via the two second half-shells 305, thereby driving the second auger 308 to revolve around the evaporator 101. Simultaneously, the second auger 308 rotates in close contact with the inner wall of the evaporator 101, frictionally contacting the second auger 308. As the second auger 308 rotates, it scrapes away the crystals adhered to the inner wall of the evaporator 101, transports the scraped crystals toward the stacking annular cavity 201, and then discharges the crystals, thus avoiding the aforementioned problem.

[0066] The second augers 308 on the two heating assemblies 300 have opposite rotation directions, but both have the function of transporting the scraped crystals to the stacking annular cavity 201 .

[0067] The embodiment of the present invention further provides an evaporation and crystallization process for fluorine-containing high-salt wastewater, comprising the following steps:

[0068] The wastewater is introduced into the evaporation tank 101, and a negative pressure environment is maintained in the evaporation tank 101. The heating component 300 is started to heat the wastewater. The wastewater solvent gradually evaporates and is collected through the collection pipe. The wastewater solute gradually precipitates and moves to the stacking annular cavity 201.

[0069] The first material port 206 is controlled to be open and the second material port 207 is controlled to be closed, so that the crystals in the stacking annular cavity 201 enter the storage cavity 204 through the first material port 206;

[0070] The first material port 206 is controlled to be closed and the second material port 207 is opened. The crystals in the storage chamber 204 enter the discharge chamber 205 through the second material port 207 . The first auger 208 is started to discharge the crystals in the discharge chamber 205 .

[0071] When the present invention is in use, wastewater is introduced into the evaporation tank 101, and a negative pressure environment in the evaporation tank 101 is maintained by the vacuum pump 103. High-temperature steam is provided to the heating component 300 through the steam supply device and the inlet pipe 306. The heating component 300 contacts and heats the wastewater, causing the wastewater solvent to evaporate and be discharged to the heat exchanger 102 through the collection pipe for condensation. The solute in the wastewater gradually precipitates and forms crystals. At the same time, the outlet pipe 307 guides the high-temperature steam in the heating component 300 into the heat exchanger 102 for condensation, ensuring that high-temperature steam flows through the heating component 300.

[0072] The output end of the second motor 106 drives the outer cylinder 209 to rotate. The heating tube 301 and the connecting piece 302 are regarded as a spiral plate. When it rotates with the outer cylinder 209, it can push the wastewater and crystals from the center to the edge along the radial direction of the evaporator 101. At the same time, the wastewater and crystals flow from the inside to the outside of the spiral plate, or from the outside to the inside of the spiral plate, and flow to both sides along the axial direction of the evaporator 101. Since one side of the spiral plate is the end wall of the evaporator 101, the wastewater and crystals can only flow to the other side of the spiral plate, that is, into the stacking annular cavity 201 at the center of the evaporator 101, thereby achieving a dual stirring effect on the wastewater along the radial and axial directions of the evaporator 101, so that the heating tube 301 is in full contact with the wastewater, thereby improving the heat exchange efficiency. At the same time, the outer cylinder 209 drives the second auger 308 to revolve around the evaporation tank 101. The second auger 308 is in close contact with the inner wall of the evaporation tank 101 and rotates by friction. Therefore, when the second auger 308 rotates, it can scrape off the crystals attached to the inner wall of the evaporation tank 101 and transport the scraped crystals to the stacking ring cavity 201.

[0073] When the outer cylinder 209 rotates to the point where the third material port 210 coincides with the first material port 206, the first material port 206 opens; when the outer cylinder 209 rotates to the point where the third material port 210 is offset from the first material port 206, the first material port 206 closes; the outer cylinder 209 and the inner gear ring 213 rotate, and the gear 215 simultaneously engages with the inner gear ring 213 and the outer gear ring 214, driving the second baffle 211 to rotate; when the fourth material port 212 coincides with the second material port 207, the second material port 207 opens; when the fourth material port 212 is offset from the second material port 207, the second material port 207 closes. Because the number of teeth and transmission ratios of the inner gear ring 213, gear 215, and outer gear ring 214 are related, the following effects are achieved: when the third inlet 210 is aligned with the first inlet 206, the fourth inlet 212 is offset from the second inlet 207; and when the third inlet 210 is offset from the first inlet 206, the fourth inlet 212 is aligned with the second inlet 207. That is, when the first inlet 206 is open, the second inlet 207 is closed, and the crystals in the stacking annular cavity 201 enter the storage cavity 204 through the first inlet 206. When the first inlet 206 is closed, the second inlet 207 is opened, and the crystals in the storage cavity 204 enter the discharge cavity 205 through the second inlet 207. The crystals are then discharged from the discharge cavity 205 by the first auger 208. This allows for continuous discharge of precipitated crystals without stopping the machine, while also preventing disruption to the negative pressure environment within the evaporator 101 and improving operating efficiency.

[0074] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The above-described embodiments merely illustrate several embodiments of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. An evaporation and crystallization device for fluorine-containing high-salt wastewater, characterized in that: The invention comprises a support and a cylindrical evaporation tank arranged on the support, wherein the evaporation tank is in a negative pressure environment and contains wastewater. A material annular cavity is formed in the evaporation tank, and crystals precipitated in the evaporation tank tend to move toward the material annular cavity. Heating components in contact with the wastewater are provided on both sides of the material annular cavity. The evaporation tank is provided with a collection pipe connected to the interior thereof for collecting evaporated wastewater solvent. An inner cylinder coaxial with the evaporator is fixed in the evaporator, and a first baffle is provided in the inner cylinder, and the first baffle divides the inner cavity of the inner cylinder into a storage cavity and a discharge cavity. A first material port for connecting the stacking annular cavity and the storage cavity is provided on the inner cylinder, and a second material port for connecting the storage cavity and the discharge cavity is provided on the first baffle, and a first auger for discharging material is provided in the discharge cavity; the first material port and the second material port are both switchable between open and closed states, and at the same time, one of the first material port and the second material port is in the open state. When the first material port is opened and the second material port is closed, the crystals in the stacking annular cavity enter the storage cavity through the first material port. When the first material port is closed and the second material port is opened, the crystals in the storage cavity enter the discharge cavity through the second material port. The first material opening is provided on the side wall of the inner cylinder, an outer cylinder is rotatably sleeved on the outer side of the inner cylinder, and a third material opening is provided on the side wall of the outer cylinder. When the outer cylinder rotates until the third material opening coincides with the first material opening, the first material opening is opened, and when the outer cylinder rotates until the third material opening is offset from the first material opening, the first material opening is closed; A second baffle is rotatably provided on the first baffle, and a fourth material opening is provided on the second baffle. The outer cylinder can drive the second baffle to rotate. When the fourth material opening coincides with the second material opening, the second material opening is opened. When the fourth material opening is offset from the second material opening, the second material opening is closed. An inner gear ring coaxial with the outer cylinder is provided on the inner wall of the outer cylinder, an outer gear ring is provided on the outer surface of the second baffle, and a gear rotatably provided on the first baffle that meshes with both the inner gear ring and the outer gear ring; The heating assembly rotates synchronously with the outer cylinder, and the heating assembly includes a plurality of heating tubes arranged in sequence along a preset trajectory, wherein the preset trajectory is a spiral line, and connecting pieces are provided between adjacent heating tubes to connect the adjacent heating tubes; A high-temperature medium flows through the heating assembly. The heating assembly further comprises two ring bodies sleeved on the outer cylinder. The two ring bodies are respectively arranged at both ends of the heating tube, and the interior of the ring bodies is communicated with the interior of the heating tube. The ring body comprises a first half shell and a second half shell that are sealed for relative rotation. The first half shell is stationary relative to the evaporator. One of the first half shells is provided with an inlet pipe for supplying high-temperature medium to the heating assembly, and the other first half shell is provided with an outlet pipe for outleting the high-temperature medium in the heating assembly. The second half shell rotates synchronously with the outer cylinder, and the two second half shells are respectively fixed to both ends of the heating tube.

2. The evaporation and crystallization device for fluorine-containing high-salt wastewater according to claim 1, characterized in that: A scraper is provided on the outer cylinder along its radial direction. The scraper is located at the edge of the third material port. When the first material port is opened and the second material port is closed, the scraper is used to send the crystals in the stacking ring cavity into the storage cavity through the first material port.

3. The evaporation and crystallization device for fluorine-containing high-salt wastewater according to claim 1, characterized in that: The preset trajectories of the two heating components rotate in opposite directions.

4. The evaporation and crystallization device for fluorine-containing high-salt wastewater according to claim 1, characterized in that: The spacing between adjacent heating tubes is positively correlated with a first distance, and the first distance is the spacing between the heating tubes and the outer tube.

5. The evaporation and crystallization device for fluorine-containing high-salt wastewater according to claim 1, characterized in that: A second auger is rotatably provided between the two second half shells. When the second auger rotates, it scrapes off the crystals attached to the inner wall of the evaporation tank and transports the scraped crystals to the stacking annular cavity.

6. An evaporation crystallization process for fluorine-containing high-salt wastewater, using the evaporation crystallization device for fluorine-containing high-salt wastewater according to any one of claims 1 to 5, characterized in that: The following steps are involved: The wastewater is passed into the evaporation tank, and the negative pressure environment in the evaporation tank is maintained. The heating component is started to heat the wastewater. The wastewater solvent gradually evaporates and is collected through the collection pipe. The wastewater solute gradually precipitates and moves to the pile ring cavity; The first material port is controlled to open and the second material port is controlled to close, and the crystals in the stacking annular cavity enter the storage cavity through the first material port; The first material port is controlled to be closed and the second material port is opened. The crystals in the storage chamber enter the discharge chamber through the second material port. The first auger is started to discharge the crystals in the discharge chamber.

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