Secondary steam cleaner of lithium salt factory MVR evaporator and cleaning method thereof

Abstract

The invention discloses a secondary steam cleaner for an MVR evaporator of a lithium salt factory and a cleaning method thereof.The cleaner comprises a cleaning assembly, a collecting bin and a material settling bin, a vertical bin dividing plate is arranged in the cleaning assembly to form a primary cleaning bin on the outer layer and a secondary cleaning bin on the inner layer, a defoaming wire mesh is arranged in the primary cleaning bin, and a secondary cleaning bin is arranged in the secondary cleaning bin; a spraying assembly is further arranged between the defoaming wire mesh and the secondary steam inlet, a primary electric precipitation assembly and a secondary electric precipitation assembly are sequentially arranged in the secondary cleaning bin from bottom to top, and cleaning assemblies are arranged above the primary electric precipitation assembly and the secondary electric precipitation assembly. The cleaner is simple and ingenious in structure, secondary steam is discharged after being subjected to primary cleaning of the primary cleaning bin and deep cleaning heating of the secondary cleaning bin, and spraying water and material particles in the primary cleaning bin are collected and precipitated by the collecting bin; and the arranged conical bin dividing plate can prevent foam generated by impact of condensate water in the collecting bin from escaping to cause secondary pollution, and the cleaning effect of secondary steam is guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of lithium salt plant production, and in particular relates to a secondary steam cleaner of an MVR evaporator in a lithium salt plant and a cleaning method thereof. Background Art

[0002] Evaporation and concentration is a key process in the preparation of battery-grade lithium salts. The commonly used complete set of equipment is the MVR evaporator, which is characterized by recycling the secondary steam in the system to reduce the demand for external energy. It is a high-efficiency and energy-saving equipment and has been widely used in many fields such as chemical industry, food and pharmaceuticals. Since the lithium salt mother liquor is highly alkaline, bubbles and froth are easily generated in the MVR separator. The foam carries the material particles into the scrubber with the secondary steam, but the current scrubber does not completely remove the foam and block the material. When the secondary steam carries the material particles into the steam compressor, it will cause the steam compressor impeller to become unstable due to material accumulation and excessive vibration, which will affect the production plan.

[0003] At present, in order to solve the above problems, for example, Chinese invention patent CN107569978A discloses a secondary steam scrubbing tower for an MVR system, which is provided with multiple tower bodies, mainly using cleaning liquid spray to absorb and discharge corrosive gases such as ammonia and hydrogen chloride in the secondary steam, and cooperates with the wire mesh in the four tower bodies to achieve the secondary steam defoaming after cleaning, but there is a problem that the defoaming wire mesh is corroded and blocked;

[0004] For example, Chinese utility model patent CN221106996U discloses an automatic defoaming device for an MVR scrubber, which uses a spray head and a wire mesh defoamer to remove foam from secondary steam, but it has the problem of secondary foam pollution caused by liquid impact;

[0005] That is, the current secondary steam cleaner still has problems such as poor cleaning effect, large heat loss and poor self-cleaning effect. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a secondary steam cleaner and a cleaning method for the MVR evaporator of a lithium salt plant. The device has a simple and ingenious structure. The cleaning component forms an outer primary cleaning chamber and an inner secondary cleaning chamber. The secondary steam is discharged after preliminary cleaning in the primary cleaning chamber and deep cleaning and heating in the secondary cleaning chamber. The spray water and material particles in the primary cleaning chamber are collected and precipitated in the collecting chamber. The conical partition plate can prevent the foam generated by the impact of condensed water in the collecting chamber from escaping, avoid secondary contamination of the secondary steam, and ensure the cleaning effect of the secondary steam.

[0007] The object of the present invention is achieved through the following technical solutions:

[0008] A secondary steam cleaner for an MVR evaporator of a lithium salt plant, comprising a cleaning component and a collecting bin and a sinking bin sequentially arranged at the bottom of the cleaning component, wherein a vertical partition plate is arranged inside the cleaning component to form an outer primary cleaning bin and an inner secondary cleaning bin, wherein the primary cleaning bin is provided with a secondary steam inlet for secondary steam to enter the primary cleaning bin, wherein a secondary steam outlet is arranged at the top of the secondary cleaning bin and is connected to a steam compressor, wherein a horizontal bracket connected to the inner wall of the cleaning component is arranged between the cleaning component and the collecting bin, wherein a conical partition plate and a plurality of vertical brackets are mounted on the horizontal bracket, wherein the plurality of vertical brackets are connected to the vertical partition plate at circumferential intervals, wherein the area of ​​the conical partition plate located in the secondary cleaning bin is a closed structure, and the area located in the primary cleaning bin is provided with multi-level holes;

[0009] Among them, a foam removal screen is arranged in the primary cleaning chamber, and a spray assembly is also arranged between the foam removal screen and the secondary steam inlet. A primary electrostatic precipitator assembly and a secondary electrostatic precipitator assembly are arranged in sequence from bottom to top in the secondary cleaning chamber, and a cleaning assembly is arranged above the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly.

[0010] In one embodiment, the distance between the secondary electrostatic precipitator assembly and the primary electrostatic precipitator assembly is not less than 1 m;

[0011] Through this embodiment, the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly set up at the same time can effectively improve the removal rate of materials and bubbles in the secondary steam, avoiding incomplete removal due to the wide distribution of fine particles of materials carried by them. At the same time, the distance between the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly is not less than 1m, that is, to avoid mutual influence between the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly.

[0012] In one embodiment, the primary electrostatic precipitator assembly includes a first cathode discharge network and a first anode dust suction network, the spacing between the first cathode discharge network and the first anode dust suction network is not greater than 200 mm, and the pores of the first cathode discharge network are smaller than the gaps of the first anode dust suction network, and the secondary electrostatic precipitator assembly includes a second cathode discharge network and a second anode dust suction network, the spacing between the second cathode discharge network and the second anode dust suction network is not greater than 50 mm, and the pores of the second cathode discharge network are smaller than the gaps of the second anode dust suction network;

[0013] In one embodiment, the first anode dust suction screen and the second anode dust suction screen both include an upper dust suction screen, a lower dust suction screen, and a material accumulation interlayer arranged between the upper dust suction screen and the lower dust suction screen;

[0014] In one embodiment, the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly are both connected to the vertical compartment plate through a fixing kit, and an insulating strip in contact with the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly is also provided in the fixing kit;

[0015] Through this embodiment, the provided insulating strips ensure the stable working performance of the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly.

[0016] In one embodiment, a gate valve is further provided between the first cathode discharge network and the first anode dust suction network, a sewage pipe connected to the secondary cleaning chamber is provided on the vertical compartment plate, the sewage pipe extends toward the outer wall of the primary cleaning chamber and passes through the sewage outlet on the outer wall of the primary cleaning chamber, and the sewage pipe is located above the gate valve and is provided close to the gate valve;

[0017] Through this embodiment, the gate valve is normally open and closed during cleaning to prevent the cleaning water from clogging the first cathode discharge network or entering the collection bin. At the same time, the drain pipe close to the gate valve and arranged above the gate valve facilitates flushing the material particles on the gate valve to the drain port.

[0018] In one embodiment, a first heat exchange component is further provided in the secondary cleaning chamber near the secondary steam outlet, and a second heat exchange component is provided in the collecting chamber. Both the first heat exchange component and the second heat exchange component are S-shaped structures formed by a plurality of heat exchange tubes connected in series, and a drain port is further provided in the middle section of one side of the collecting chamber;

[0019] Through this embodiment, the first heat exchange component arranged near the secondary steam outlet can increase the temperature and dryness of the secondary steam, reduce condensation, make the steam dryer, and the heat loss when discharged from the system after reheating is relatively small, thereby improving the thermal energy conversion efficiency and reducing the probability of material accumulation on the impeller of the steam compressor. The second heat exchange component arranged can heat the condensed water in the collection bin through the conical partition plate, thereby maintaining the calorific value in the bin and avoiding crystallization of materials and heat loss of secondary steam due to temperature drop in the cleaner. The drain port opened in the middle section of one side of the collection bin is used to control the water level in the collection bin to maintain the internal temperature of the cleaner.

[0020] In one embodiment, the diameter of the multi-stage holes of the conical compartment plate in the primary cleaning compartment gradually decreases toward the secondary cleaning compartment;

[0021] Through this implementation, the condensed water sprayed from the primary cleaning chamber can enter the collecting chamber from the large-aperture holes on the edge of the conical partition plate as much as possible, while the small-aperture holes close to the secondary cleaning chamber can suppress the large bubbles and low-temperature water vapor in the collecting chamber from entering the secondary cleaning chamber, thereby avoiding contamination of the secondary steam. At the same time, since the outside of the primary cleaning chamber is cooled faster, the condensed water in the collecting chamber heated by the second heat exchange component has a higher flow rate through the outside of the primary cleaning chamber, making the heat in the chamber uniform.

[0022] In one embodiment, a discharge pipe is connected to the bottom of the sinking bin, and a sinking net is provided at the connection between the sinking bin and the collecting bin, the sinking net comprises an upper sinking wire screen, a lower sinking wire screen and a material control interlayer located between the upper sinking wire screen and the lower sinking wire screen, the aperture of the lower wire screen is not less than the diameter of the material particles that can be carried by the foam in the secondary steam, the aperture of the upper sinking wire screen is larger than the aperture of the lower sinking wire screen, and an air pipe connected to the air source is also provided below the sinking net, and a plurality of sealing nozzles are opened on the air pipe.

[0023] The present invention also provides a secondary steam cleaning method for an MVR evaporator in a lithium salt plant, comprising the following steps:

[0024] Step S1, introducing secondary steam from one side of the cleaning component into the primary cleaning chamber of the outer layer of the cleaning component;

[0025] Step S2: In the primary cleaning chamber, condensed water is used to preliminarily break the foam in the secondary steam and increase the liquid holding capacity of the material particles;

[0026] Step S3, passing the secondary steam through the fan-shaped defoaming screen to break the foam therein again;

[0027] Step S4, the material particles pass through the conical compartment plate under the action of the spray water and enter the collection bin at the bottom of the cleaning component. At the same time, the secondary steam is sent into the secondary cleaning bin located in the inner layer of the cleaning component by the suction force of the steam compressor to achieve deep cleaning;

[0028] Step S5, under the suction of the steam compressor, the secondary steam passes through the primary electrostatic precipitator component and the secondary electrostatic precipitator component from bottom to top in the secondary cleaning chamber to remove bubbles and small particles again, and then enters the steam compressor after being heated and dried by the first heat exchange component, thereby realizing the recycling of the secondary steam of the MVR system of the lithium salt plant and avoiding the steam compressor impeller from stopping due to material accumulation.

[0029] The beneficial effects of the present invention are:

[0030] (1) The secondary steam cleaner provided by the present invention has a simple and ingenious structure and is easy to maintain. The primary cleaning chamber and the secondary cleaning chamber form a cleaning component, and the inner and outer layers correspond to each other, so that the secondary steam passes through the spraying and defoaming of the primary cleaning chamber, and then directly enters the inner secondary cleaning chamber under the suction of the steam compressor to further remove material particles and bubbles. The collection chamber at the bottom of the cleaning component collects the spray water and material particles generated in the primary cleaning chamber. At the same time, the conical partition plate between the cleaning component and the collecting chamber can prevent the foam generated by the impact of condensed water in the collecting chamber from escaping, thereby avoiding secondary pollution and ensuring the cleanliness of the secondary steam.

[0031] (2) Using condensed water and raw steam to maintain the internal temperature of the cleaner and avoid secondary steam temperature drop has a significant energy-saving effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein:

[0033] Figure 1 Shows a schematic diagram of the structure of the present invention;

[0034] Figure 2 A schematic diagram showing the structure of the secondary cleaning chamber of the present invention is shown;

[0035] Figure 3 The schematic diagram of the structure of the foam removal screen of the present invention is shown;

[0036] Figure 4 The structural schematic diagram of the conical compartment plate of the present invention is shown;

[0037] Figure 5 The structural schematic diagram of the sinking net of the present invention is shown;

[0038] Figure 6 A schematic diagram showing the structure of the first anode dust suction net and the second anode dust suction net of the present invention is shown;

[0039] Figure 7 A schematic diagram showing the connection of the secondary steam cleaner of the present invention to a steam compressor;

[0040] In the drawings, like reference numerals are used for like parts. The drawings are not necessarily to scale.

[0041] Reference numerals:

[0042] 100-secondary steam cleaner, 1-cleaning component, 2-collecting bin, 3-sinking bin, 4-vertical partition plate, 5-secondary steam outlet, 6-secondary steam inlet, 7-horizontal bracket, 8-conical partition plate, 9-vertical bracket, 10-foam removal screen, 11-first heat exchange component, 12-second heat exchange component, 13-gate valve, 14-primary electrostatic precipitator component, 15-secondary electrostatic precipitator component, 16-first cleaning nozzle, 17-second cleaning nozzle, 18-drain pipe, 19-drain port, 20-annular wire mesh bracket, 21-annular condensate pipe bracket, 22-manhole for inspection, 23-second heat exchange bracket, 24-discharge pipe, 25-sinking net, 26-air pipe, 27-liquid level meter, 28-drain flushing pipe, 29-sprinkler head, 30-raw steam inlet, 31-raw steam outlet, 32-breathing tube, 33-fixing kit, 34-insulating strip, 35-steel plate, 36-enclosed structure, 37-holes, 38-dust suction upper screen, 39-dust suction lower screen, 40-accumulated material interlayer, 41-gas-liquid separator, 42-forced evaporator, 43-transfer tank, 44-circulation pump, 45-steam compressor, 46-forced circulation pump, 101-primary cleaning chamber, 102-secondary cleaning chamber, 1401-first cathode discharge screen, 1402-first anode dust suction screen, 1501-second cathode discharge screen, 1502-second anode dust suction screen, 2501-sinking material upper screen, 2502-sinking material lower screen, 2503-material control interlayer. DETAILED DESCRIPTION

[0043] The present invention will be further described below in conjunction with the accompanying drawings.

[0044] The present invention provides a secondary steam cleaner for MVR evaporator of lithium salt plant, such as Figures 1 to 4 As shown, it includes a cleaning component 1 and a collecting bin 2 and a sinking bin 3 which are sequentially arranged at the bottom of the cleaning component 1. A vertical partition plate 4 is arranged inside the cleaning component 1 to form an outer primary cleaning bin 101 and an inner secondary cleaning bin 102. The primary cleaning bin 101 is provided with a secondary steam inlet 6 for secondary steam to enter the primary cleaning bin 101. The top of the secondary cleaning bin 102 is provided with a secondary steam outlet 5 which is connected to a steam compressor. A horizontal bracket 7 connected to the inner wall of the cleaning component 1 is arranged between the cleaning component 1 and the collecting bin 2. A conical partition plate 8 and a plurality of vertical brackets 9 are installed on the horizontal bracket 7. The plurality of vertical brackets 9 are connected to the vertical partition plate 4 at circumferential intervals. The area where the conical partition plate 8 is located in the secondary cleaning bin 102 is a closed structure 36, and the area located in the primary cleaning bin 101 is provided with multi-level holes 37.

[0045] Among them, a foam removal screen 10 is arranged in the primary cleaning chamber 101, and a spray assembly is also arranged between the foam removal screen 10 and the secondary steam inlet 6. A primary electric dust removal assembly 14 and a secondary electric dust removal assembly 15 are arranged in sequence from bottom to top in the secondary cleaning chamber 102, and a cleaning assembly is arranged above the primary electric dust removal assembly 14 and the secondary electric dust removal assembly 15;

[0046] It should be noted that if Figure 1 As shown, the primary cleaning bin 101 and the secondary cleaning bin 102 are respectively used as the outer layer and the inner layer of the cleaning component 1 through the vertical partition plate 4, and the vertical supports arranged at intervals ensure the structural strength while allowing the secondary steam to enter the secondary cleaning bin 102 from the primary cleaning bin 101 through the gap between the vertical supports 9, that is, the secondary steam containing the material first enters the primary cleaning bin 101 from one side of the cleaning component 1, and after being sprayed and defoamed in the primary cleaning bin 101, it enters the secondary cleaning bin 102 of the inner layer through the gap of the vertical support under the suction of the steam compressor, and further removes the material particles and bubbles. At this time, the collecting bin 2 located at the bottom of the cleaning component 1 collects and precipitates the spray water generated in the primary cleaning bin 101 and the material particles after absorbing water. At the same time, the conical partition plate 8 between the cleaning component 1 and the collecting bin 2 prevents the foam generated by the impact of condensed water in the collecting bin 2 from escaping, thereby avoiding secondary pollution and ensuring the cleanliness of the secondary steam.

[0047] Specifically, Figure 1 and Figure 3 As shown, the foam removal screen 10 is a fan-shaped structure, which is arranged on the annular screen support 20 at the bottom of the primary cleaning chamber 101. The foam removal screen 10 is a single-layer structure, and a layer of janus coating is attached to its surface. The foam removal screen 10 is made of a hydrophilic material, and its gap is 8mm. The steel wire is made of stainless steel, with a diameter of 3mm and a thickness of 1.5mm. The upper surface of the janus coating is hydrophilic and the lower surface is hydrophobic. The upper surface absorbs the bubble material to form droplets, and the lower surface discharges the material droplets, so that the liquid holding capacity of the bubble material in the secondary steam after spraying is increased, and the condensed water sprayed on the screen when passing through the hydrophilic screen is brought into the collection chamber 2;

[0048] Specifically, Figure 2 As shown, the distance between the secondary electrostatic precipitator assembly 15 and the primary electrostatic precipitator assembly 14 is not less than 1m, that is, the primary electrostatic precipitator assembly 14 and the secondary electrostatic precipitator assembly 15 set at the same time can effectively improve the removal rate of materials and bubbles in the secondary steam, and avoid incomplete removal due to the wide distribution of fine particles of materials carried by them. At the same time, the distance between the primary electrostatic precipitator assembly 14 and the secondary electrostatic precipitator assembly 15 is not less than 1m, that is, the mutual influence between the primary electrostatic precipitator assembly 14 and the secondary electrostatic precipitator assembly 15 is avoided;

[0049] In one embodiment, Figure 4As shown, the aperture of the multi-stage holes 37 of the conical partition plate 8 located in the primary cleaning chamber 101 gradually decreases toward the secondary cleaning chamber 102, from the 14mm hole 37 to 4mm. On the one hand, the condensed water sprayed from the primary cleaning chamber 101 can enter the collecting chamber 2 from the large-aperture holes 37 located at the edge of the conical partition plate as much as possible. On the other hand, the small-aperture holes 37 arranged near the secondary cleaning chamber can inhibit the large bubbles and low-temperature water vapor in the collecting chamber 2 from entering the secondary cleaning chamber 102, which can effectively prevent the bubbles generated by the condensed water in the collecting chamber 2 from escaping, and further avoid the occurrence of secondary pollution.

[0050] Furthermore, if Figure 2 As shown, the primary electrostatic precipitator assembly 14 includes a first cathode discharge network 1401 and a first anode dust suction network 1402, the spacing between the first cathode discharge network 1401 and the first anode dust suction network 1402 is not greater than 200 mm, the pores of the first cathode discharge network 1401 are smaller than the gaps of the first anode dust suction network 1402, and the secondary electrostatic precipitator assembly 15 includes a second cathode discharge network 1501 and a second anode dust suction network 1502, the spacing between the second cathode discharge network 1501 and the second anode dust suction network 1502 is not greater than 50 mm, and the pores of the second cathode discharge network 1501 are smaller than the gaps of the second anode dust suction network 1502 to ensure the dust removal effect;

[0051] In one embodiment, Figure 6 As shown, the first cathode discharge net 1401 is a single-layer structure with a pore size of 10 mm, the second cathode discharge net 1501 is a single-layer structure with a pore size of 6 mm, the first anode dust suction net 1402 and the second anode dust suction net 1502 both include an upper dust suction screen 38, a lower dust suction screen 39, and a material accumulation interlayer 40 disposed between the upper dust suction screen 38 and the lower dust suction screen 39 to avoid high temperature deformation, the gap of the first anode dust suction net 1402 is 20 mm, and the gap of the second anode dust suction net 1502 is 12 mm;

[0052] Specifically, the primary electrostatic precipitator assembly 14 and the secondary electrostatic precipitator assembly 15 are connected to the vertical compartment plate 4 through a fixing kit 33. An insulating strip 34 in contact with the primary electrostatic precipitator assembly 14 and the secondary electrostatic precipitator assembly 15 is also provided in the fixing kit 33. The first cathode discharge net 1401, the first anode dust suction net 1402, the second cathode discharge net 1501 and the second anode dust suction net 1502 are coated with high temperature and corrosion resistant insulating paint 50 mm outward within the range of the insulating strip 34 to ensure the stable working performance of the electrostatic precipitator. The edge strip 34 is made of polytetrafluoroethylene, polyetheretherketone, polyimide, HTPDMS modified epoxy resin, etc. The insulating coating material includes epoxy resin coating, polyurethane coating, acrylic insulating paint, high temperature resistant ceramic insulating coating, etc. The anode material of the primary electrostatic precipitator assembly 14 and the secondary electrostatic precipitator assembly 15 can be selected from stainless steel, conductive fiberglass, carbon steel, titanium alloy, etc. The cathode material of the primary electrostatic precipitator assembly 14 and the secondary electrostatic precipitator assembly 15 can be selected from lead antimony alloy, 316L stainless steel, titanium alloy, etc.

[0053] In one embodiment, Figure 1 As shown, a gate valve 13 is further provided between the first cathode discharge net 1401 and the first anode dust suction net 1402, and a sewage pipe 18 connected to the secondary cleaning bin 102 is provided on the vertical compartment plate 4, and the sewage pipe 18 passes through the sewage outlet 19 on the outer wall of the primary cleaning bin 101, and the sewage pipe 18 is located above the gate valve 13 and is arranged close to the gate valve 13, that is, the gate valve 13 is normally open and closed during cleaning, and is used to block the cleaning water from passing through the first cathode discharge net 1401 or entering the collection bin 2 during cleaning, so as to prevent the materials on the first anode dust suction net 1402 and the second anode dust suction net 1502 from entering the collection bin 2, and at the same time prevent the cleaned materials from gathering on the first cathode discharge net 1401. Since the first cathode discharge net 1401 is not easily cleaned by the nozzle, the maintenance difficulty is reduced, and the sewage flushing pipe 28 is arranged on the upper part of the gate valve 13, and the material particles on the gate valve 13 are flushed out to the sewage outlet 19 after the cleaning is completed;

[0054] In one embodiment, Figure 1 and Figure 2 As shown, a first heat exchange component 11 is further provided in the secondary cleaning chamber 102 near the secondary steam outlet 5, and a second heat exchange component 12 is provided in the collecting chamber 2. Both the first heat exchange component 11 and the second heat exchange component 12 are S-shaped structures formed by a plurality of heat exchange tubes connected in series, and a drain port is further provided in the middle section of one side of the collecting chamber 2;

[0055] It should be noted that the first heat exchange component 11 arranged near the secondary steam outlet 5 can increase the temperature and dryness of the secondary steam, reduce condensation, and make the steam dryness higher. The heat loss when discharged from the system after reheating is relatively small, which reduces the exhaust loss, improves the heat energy conversion efficiency, and can also reduce the probability of material accumulation on the impeller of the steam compressor. The second heat exchange component 12 is arranged to heat the condensed water in the collection bin 2 to pass through the conical partition plate 8, which can maintain the calorific value in the bin, avoid crystallization of materials due to temperature drop in the cleaner and heat loss of the secondary steam. At the same time, since the outer side of the primary cleaning bin 101 cools faster, the aperture of the outer hole 37 of the conical partition plate 8 is larger than the aperture of the inner hole 37, that is, the second heat exchange component 12 heats the condensed water in the collection bin 2 through the outer side of the primary cleaning bin 101. The flow rate is larger, so that the heat in the bin is uniform, and the drain port opened in the middle section of one side of the collection bin 2 is used to control the water level in the collection bin 2 to maintain the internal temperature of the cleaner;

[0056] Specifically, Figure 1 As shown, the heat source of the second heat exchange component 12 in the collection bin is raw steam, one end of the second heat exchange component 12 is a raw steam inlet 30, and the other end is a raw steam outlet 31, and the heat source of the first heat exchange component 11 is also raw steam.

[0057] In one embodiment, Figure 1 As shown, a liquid level gauge 27 and a liquid discharge port are provided in the collection bin 2, and the liquid level gauge 27 is provided on both outer sides of the collection bin 2 to avoid misjudgment of faults;

[0058] In one embodiment, Figure 5 As shown, the bottom of the sinking bin 3 is connected to a discharge pipe 24, and a sinking net 25 is provided at the connection between the sinking bin 3 and the collecting bin 2. The sinking net 25 includes an upper sinking screen 2501, a lower sinking screen 2502, and a material control interlayer 2503 located between the upper sinking screen 2501 and the lower sinking screen 2502. The aperture of the lower sinking screen 2502 is not less than the diameter of the material particles that the foam in the secondary steam can carry, and the aperture of the upper sinking screen 2501 is larger than the aperture of the lower sinking screen 2502. The aperture of the net 2502 is 0.5 mm. An air pipe 26 connected to the air source is also provided below the sinking net 25. A plurality of sealing nozzles are provided on the air pipe 26. The sinking net 25 is used to seal the material particles in the collection bin 2 in the sinking bin 3. The sealing nozzle can only spray air when the compressed air is turned on to push the seal to clean the material particles on the sinking net 25 and the second heat exchange component 12 during the cooking effect. The discharge port is used to be opened after cleaning to discharge impurities in the collection bin 2 and the sinking bin 3.

[0059] In one embodiment, the present invention further provides a secondary steam cleaning method for an MVR evaporator in a lithium salt plant, comprising the following steps:

[0060] Step S1, introducing secondary steam from one side of the cleaning component into the primary cleaning chamber of the outer layer of the cleaning component;

[0061] Step S2: In the primary cleaning chamber, condensed water is used to preliminarily break the foam in the secondary steam and increase the liquid holding capacity of the material particles;

[0062] Step S3, passing the secondary steam through the fan-shaped defoaming screen to break the foam therein again;

[0063] Step S4, the material particles pass through the conical compartment plate under the action of the spray water and enter the collection bin at the bottom of the cleaning component. At the same time, the secondary steam is sent into the secondary cleaning bin located in the inner layer of the cleaning component by the suction force of the steam compressor to achieve dry and wet separation;

[0064] Step S5, under the suction of the steam compressor, the secondary steam passes through the primary electrostatic precipitator component and the secondary electrostatic precipitator component from bottom to top in the secondary cleaning chamber to remove bubbles and small particles again, and then enters the steam compressor after being heated and dried by the first heat exchange component, thereby completing the recycling of the secondary steam;

[0065] Furthermore, it also includes:

[0066] Step S6, during the cooking period of the MVR evaporator, the cathode and anode nets of the primary and secondary electrostatic precipitator components are flushed. To prevent excessive materials from entering the collection bin to block the conical partition plate and the sinking net and accumulating in the sinking bin, the normally open gate valve in the secondary cleaning bin is closed during cleaning, and the cleaning water is directly discharged from the sewage pipe to the cleaner. After the flow of the sewage pipe becomes smaller, the sewage flushing pipe is opened to flush the materials on the upper side of the gate valve. The flushing effect can be checked through the lens on the sewage pipe. After flushing, the gate valve is opened to flush the secondary cleaning bin, the first cathode discharge net and the conical partition plate for about 20 minutes. After the secondary cleaning bin is cleaned, the gate valve is closed, the valve on the breathing pipe 32 is opened, and then the air pipe of the sinking bin is opened to perform gas explosion loosening cleaning on the second heat exchange component and the sinking net for 30 minutes, and then the discharge pipe valve is opened for discharge;

[0067] It should be noted that the cleaning method provided in this embodiment uses multiple compartments to achieve dry-wet separation and avoid secondary pollution, uses existing steam condensate as a cleaning medium, and uses live steam as a heat source to maintain the calorific value of the recycled condensate and ensure the temperature inside the cleaner, which has a good energy-saving and consumption-reducing effect. The secondary steam cleaned and heated by the first and second cleaning compartments is more conducive to the operation of the steam compressor.

[0068] In one embodiment, Figure 7As shown, the secondary steam inlet 6 of the secondary steam cleaner 100 provided by the present invention is connected to the gas-liquid separator 41, and the secondary steam containing materials in the gas-liquid separator 41 enters the primary cleaning chamber 101 through the secondary steam inlet 6 on one side of the cleaning component 1 of the secondary steam cleaner, and the secondary steam inlet 6 is inserted along the tangential direction of the cleaning component 1, so that the large particles in the secondary steam pass through the defoaming screen 10 at a higher speed under the action of centrifugal force, and the secondary steam outlet 5 at the top of the secondary cleaning chamber 102 in the cleaning component 1 is connected to the steam compressor 45, and the steam compressor 45 sends the secondary steam to the forced evaporator 42 and recovers it to the gas-liquid separator 41, and a forced circulation pump 46 is arranged between the gas-liquid separator 41 and the forced evaporator 42 to recycle the secondary steam and reduce the cost, and the bottom of the secondary steam cleaner is sequentially connected to the transfer tank 43 and the circulation pump 44, and the outlet of the circulation pump 44 is connected to the secondary steam cleaner 100;

[0069] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "bottom", "top", "front", "back", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0070] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. A secondary steam cleaner for MVR evaporator in lithium salt plant, characterized in that: It comprises a cleaning component and a collecting bin and a sinking bin sequentially arranged at the bottom of the cleaning component, a vertical partition plate is arranged inside the cleaning component to form an outer primary cleaning bin and an inner secondary cleaning bin, the primary cleaning bin is provided with a secondary steam inlet to allow secondary steam to enter the primary cleaning bin, a secondary steam outlet is arranged on the top of the secondary cleaning bin and is connected to a steam compressor, a horizontal bracket connected to the inner wall of the cleaning component is arranged between the cleaning component and the collecting bin, a conical partition plate and a plurality of vertical brackets are installed on the horizontal bracket, a plurality of the vertical brackets are connected to the vertical partition plate at circumferential intervals, the area of ​​the conical partition plate located in the secondary cleaning bin is a closed structure, and the area located in the primary cleaning bin is provided with multi-level holes; Among them, a foam removal screen is arranged in the primary cleaning chamber, and a spray assembly is also arranged between the foam removal screen and the secondary steam inlet. A primary electrostatic precipitator assembly and a secondary electrostatic precipitator assembly are arranged in sequence from bottom to top in the secondary cleaning chamber, and a cleaning assembly is arranged above the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly.

2. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 1, characterized in that: The distance between the secondary electrostatic precipitator assembly and the primary electrostatic precipitator assembly is not less than 1 m.

3. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 2, characterized in that: The primary electrostatic precipitator assembly includes a first cathode discharge network and a first anode dust suction network, the spacing between the first cathode discharge network and the first anode dust suction network is not greater than 200 mm, and the pores of the first cathode discharge network are smaller than the gaps of the first anode dust suction network. The secondary electrostatic precipitator assembly includes a second cathode discharge network and a second anode dust suction network, the spacing between the second cathode discharge network and the second anode dust suction network is not greater than 50 mm, and the pores of the second cathode discharge network are smaller than the gaps of the second anode dust suction network.

4. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 3, characterized in that: The first anode dust suction screen and the second anode dust suction screen both include an upper dust suction screen, a lower dust suction screen, and a material accumulation interlayer arranged between the upper dust suction screen and the lower dust suction screen.

5. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 1, characterized in that: The primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly are both connected to the vertical compartment plate through a fixing kit, and an insulating strip in contact with the primary electrostatic precipitator assembly and the secondary electrostatic precipitator assembly is also provided in the fixing kit.

6. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 3, characterized in that: A gate valve is also arranged between the first cathode discharge network and the first anode dust suction network. A drain pipe connected to the secondary cleaning chamber is arranged on the vertical compartment plate. The drain pipe extends toward the outer wall of the primary cleaning chamber and passes through the drain port on the outer wall of the primary cleaning chamber. The drain pipe is located above the gate valve and is arranged close to the gate valve.

7. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 1, characterized in that: A first heat exchange component is also arranged in the secondary cleaning chamber near the secondary steam outlet, and a second heat exchange component is arranged in the collecting chamber. Both the first heat exchange component and the second heat exchange component are S-shaped structures formed by a plurality of heat exchange tubes connected in series, and a drain port is also opened in the middle section on one side of the collecting chamber.

8. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 1, characterized in that: The diameters of the multi-stage holes of the conical compartment plate located in the primary cleaning compartment gradually decrease toward the secondary cleaning compartment.

9. The secondary steam cleaner for MVR evaporator of lithium salt plant according to claim 1, characterized in that: A discharge pipe is connected to the bottom of the sinking bin, and a sinking net is arranged at the connection between the sinking bin and the collecting bin. The sinking net comprises an upper sinking screen, a lower sinking screen and a material control interlayer located between the upper sinking screen and the lower sinking screen. The aperture of the lower sinking screen is not less than the diameter of the material particles that can be carried by the foam in the secondary steam, the aperture of the upper sinking screen is larger than the aperture of the lower sinking screen, and an air pipe connected to the air source is also arranged below the sinking net, and a plurality of sealing nozzles are opened on the air pipe.

10. A secondary steam cleaning method for an MVR evaporator in a lithium salt plant, based on the secondary steam cleaning method for an MVR evaporator in a lithium salt plant according to any one of claims 1 to 9, characterized in that: The steps include: Step S1, introducing secondary steam from one side of the cleaning component into the primary cleaning chamber of the outer layer of the cleaning component; Step S2: In the primary cleaning chamber, condensed water is used to preliminarily break the foam in the secondary steam and increase the liquid holding capacity of the material particles; Step S3, passing the secondary steam through the fan-shaped defoaming screen to break the foam therein again; Step S4, the material particles pass through the conical compartment plate under the action of the spray water and enter the collection bin at the bottom of the cleaning component. At the same time, the secondary steam is sent into the secondary cleaning bin located in the inner layer of the cleaning component by the suction force of the steam compressor to achieve deep cleaning; Step S5, under the suction of the steam compressor, the secondary steam passes through the primary electrostatic precipitator component and the secondary electrostatic precipitator component from bottom to top in the secondary cleaning chamber to remove bubbles and small particles again, and then enters the steam compressor after being heated and dried by the first heat exchange component, thereby realizing the recycling of the secondary steam of the MVR system of the lithium salt plant and avoiding the steam compressor impeller from stopping due to material accumulation.

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