Evaporation and concentration system suitable for lithium sulfate purification

Abstract

The utility model discloses an evaporation and concentration system suitable for lithium sulfate purification, which is characterized in that an outlet of a raw material tank is sequentially connected with a cold side of a condensate water preheater and a cold side of a non-condensable steam preheater through an outlet of a feeding pump, and then is connected with a tube pass inlet of a heater together with an outlet pipeline of a material circulating pump; a tube pass outlet of the heater is connected with a material inlet of the integrated separator, and a material outlet of the separator is connected with an inlet of the material circulating pump; a secondary steam outlet of the integrated separator is connected with an inlet of a steam compressor through a scrubber tower, and a compressed steam pipe is connected with a shell pass steam inlet of a heater; a shell pass condensed water outlet of the heater is connected with an inlet of a condensed water tank; an outlet of the condensed water tank is connected with a hot side of the condensed water preheater through a condensed water pump; a shell pass extraction opening of the heater is connected with the hot side of the non-condensable steam preheater through a non-condensable gas conveying pipe, and a hot side outlet of the condenser is connected with a vacuumizing system. The system is high in evaporation efficiency and low in operation cost and equipment investment.

Description

Technical Field

[0001] The utility model relates to an evaporation and concentration system, in particular to an evaporation and concentration system suitable for purifying lithium sulfate, and belongs to the technical field of lithium purification equipment. Background Art

[0002] Lithium sulfate, a common industrial product, plays a vital role in medicine, industry, and chemical analysis. It is used in the production of various pharmaceuticals, including mood stabilizers and depression treatments. In industrial production, lithium sulfate is used to manufacture electronic components, piezoelectric chips, and glass-ceramics, impacting every aspect of our lives.

[0003] Lithium sulfate concentration often utilizes an MVR evaporation and concentration design. The feed is preheated in a preheater via a feed pump before entering the evaporation and concentration system. As evaporation progresses, the lithium sulfate solution reaches the desired concentration and is discharged via a discharge pump. The secondary steam generated by evaporation and concentration is heated and pressurized by a steam compressor. The compressed steam is then recycled as a heat source for the evaporator. The condensed water is collected, heat exchanged with the feed, and discharged for reuse. Lithium sulfate is also a key raw material in the industrial production of lithium carbonate. The commonly used sulfuric acid process for producing lithium carbonate requires a relatively high concentration of lithium sulfate, necessitating the development of an efficient lithium sulfate concentration system.

[0004] Chinese utility model patent publication number CN 207445617U discloses an MVR evaporator, comprising a separator, compressor, evaporator, circulation pump, and heat exchanger. The MVR evaporator process involves compressing secondary steam from the evaporation chamber, increasing its pressure and temperature, thereby increasing its enthalpy. The secondary steam is then sent to a heating chamber for use as heating steam, maintaining the liquid in a boiling state while the heating steam condenses into water.

[0005] However, the above evaporator solution and the prior art have the following defects: 1. The secondary steam at the separator outlet directly enters the steam compressor for pressure boosting without passing through the scrubber for cleaning and drying, which reduces the system concentration efficiency and the service life of the steam compressor;

[0006] 2. Imported materials are not preheated, and the heat of steam condensate and non-condensable gas is not recycled, resulting in high operating costs;

[0007] 3. The device is designed with two sets of vertical evaporators, which makes the device taller and the steel structure cost higher;

[0008] 4. The evaporator cannot be opened or closed according to different feed concentrations, and the device has poor operating flexibility. Utility Model Content

[0009] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and utility model title of this application, and such simplifications or omissions shall not be used to limit the scope of the present invention.

[0010] In view of the above problems and / or the problems existing in the prior art, the present utility model is proposed.

[0011] The purpose of the utility model is to overcome the problems existing in the prior art and provide an evaporation concentration system suitable for the purification of lithium sulfate, so as to achieve an increase in the concentration of lithium sulfate and realize the heat recovery of condensed water, non-condensable gas and secondary steam in the production process. The concentrated lithium sulfate can meet the production requirements of lithium carbonate produced by the sulfuric acid process and improve the yield of lithium carbonate.

[0012] To solve the above technical problems, the utility model provides an evaporation and concentration system suitable for lithium sulfate purification, comprising a raw material tank, the outlet of the raw material tank being connected to the inlet of a feed pump, the outlet of the feed pump being connected to the cold side inlet of a condensate preheater, the cold side outlet of the condensate preheater being connected to the cold side inlet of a non-condensing steam preheater, the cold side outlet of the non-condensing steam preheater and the outlet pipe of a material circulation pump being connected together to the tube-side inlet of a heater, the tube-side outlet of the heater being connected to the material inlet of an integrated separator, and the bottom discharge port of the integrated separator being connected to the inlet of the material circulation pump;

[0013] The secondary steam outlet of the integrated separator is connected to the air inlet of the scrubber, the air outlet of the scrubber is connected to the inlet of the steam compressor, and the outlet of the steam compressor is connected to the shell-side steam inlet of the heater through a compressed steam pipe;

[0014] The shell-side condensate outlet of the heater is connected to the inlet of the condensate tank, and the outlet of the condensate tank is connected to the hot side inlet of the condensate preheater through a condensate pump;

[0015] The shell side exhaust port of the heater is connected to the hot side inlet of the non-condensing steam preheater through a non-condensing gas conveying pipe, the hot side outlet of the non-condensing steam preheater is connected to the hot side inlet of the condenser, and the hot side outlet of the condenser is connected to the vacuum system.

[0016] As an improvement of the present invention, the circulating water delivery pipe is connected to the cold side inlet of the condenser, the cold side outlet of the condenser and the outlet circulating pipe of the washing liquid circulation pump are commonly connected to the spray port on the upper part of the washing tower, and the drain outlet at the bottom of the washing tower is connected to the inlet of the washing liquid circulation pump through the washing liquid circulation pipe.

[0017] As a further improvement of the present invention, the middle part of the integrated separator is a mother liquid evaporation section, the upper end of the mother liquid evaporation section is provided with a defoaming section that tapers upward, and the top center of the defoaming section is provided with a secondary steam outlet; the lower part of the barrel of the mother liquid evaporation section is provided with a tapered barrel that gradually narrows downward, and the middle and lower inner cavity of the mother liquid evaporation section is provided with a feed guide pipe, the lower end of the feed guide pipe extends from the tapered wall of the tapered barrel and is provided with a material inlet, the upper end of the feed guide pipe extends toward the axis of the mother liquid evaporation section, and the upper end is provided with a feed bell mouth;

[0018] The lower end of the conical cylinder is connected to a material accumulation section extending downward, and a concentrated material outlet is provided at the lower end of the material accumulation section; a bypass port is provided on the side wall of the middle section of the material accumulation section, and a separator heat exchange section extending laterally outward is connected to the bypass port flange;

[0019] The separator heat exchange section includes a heat exchange section shell, the inner port of the heat exchange section shell is connected to the bypass port flange through the inner tube sheet flange, the outer port of the heat exchange section shell is provided with an outer tube sheet flange, the inner tube sheet flange and the outer tube sheet flange are connected by multiple heat transfer tubes, and the outer side of the outer tube sheet flange is connected to a pipe box;

[0020] A removable tube-side partition is provided on the middle cross section of the material accumulation section. The root of the removable tube-side partition is connected to the middle diameter line of the inner end tube sheet flange to separate the heat transfer tubes into two groups, upper and lower.

[0021] As a further improvement of the present invention, a partition reinforcing ring is provided on the circumference of the middle section of the material accumulation section, and the end of the detachable pipe-side partition is embedded in the groove of the partition reinforcing ring.

[0022] As a further improvement of the present invention, a heating steam inlet is provided at the distal top of the heat exchange section shell, the heating steam inlet is connected to the compression steam pipe, and a condensate outlet is provided at the proximal bottom of the heat exchange section shell.

[0023] Compared with the existing technology, the utility model has achieved the following beneficial effects: 1. It can be used for the concentration of lithium sulfate raw material liquid with a concentration of 10%-20%, ensuring the high efficiency and environmental protection of the subsequent production of lithium carbonate from lithium sulfate; the system recovers the residual heat of condensed water through a condensed water preheater, recovers the extra heat of non-condensable gas through a non-condensable gas preheater, and recovers the residual heat of evaporated secondary steam through a steam compressor, effectively avoiding the waste of steam and electric energy in the production process, and also improving the operating efficiency of the lithium sulfate concentration system.

[0024] 2. An integrated separator is designed to effectively combine the horizontal shell and tube evaporator with the concentration separator, effectively reducing the equipment height of the concentration device, reducing the steel structure and equipment manufacturing costs of the device, and also meeting the restrictions on the overall height of the production device in local areas, making this concentration device suitable for more occasions at home and abroad.

[0025] 3. An annular flushing pipe and a wire mesh demister are installed on the conical top of the integrated separator. The wire mesh demister absorbs droplets and dust in the secondary steam. The separator and the wire mesh demister are regularly flushed with hot water in the annular flushing pipe to ensure long-term and stable operation of the concentration device.

[0026] 4. The mother liquor evaporation section of the integrated separator effectively increases the surface area of ​​the concentrated mother liquor during evaporation by increasing the cross-sectional area of ​​the mother liquor evaporation section and the feed bell mouth device, greatly improving the efficiency of lithium sulfate during pressure reduction evaporation.

[0027] 5. A heat exchange section is extended horizontally from the material accumulation section at the bottom of the integrated separator. The material is passed into the heat exchange section through a detachable tube baffle to exchange heat with the shell steam. This reduces the length of the material circulation pipe and the heat loss of the material circulation, reduces the investment cost of the circulation pipeline, and also increases the evaporation temperature of the separator, meeting the overall goal of reducing costs and increasing efficiency of the concentration device.

[0028] 6. A detachable device for the separator heat exchange section is designed. Taking into account the changes in the concentration of imported lithium sulfate, the integrated separator heat exchange section can be quickly disassembled through detachable tube baffles, tube sheet flanges, detachable tube box heads and other equipment parts through the rollers at the bottom of the heat exchange section, changing the entire system from a dual heater to a single heater, which can be adjusted according to different feed and discharge concentration requirements, greatly increasing the production flexibility of the device and reducing operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. The drawings are only provided for reference and explanation, and are not intended to limit the present invention. Among them:

[0030] Figure 1 This is a flow chart of an evaporation and concentration system suitable for purification of lithium sulfate according to the present invention;

[0031] Figure 2 It is a three-dimensional diagram of the integrated separator in the utility model;

[0032] Figure 3 This is a cross-sectional view of the integrated separator in the present utility model;

[0033] Figure 4 This is a three-dimensional diagram of the integrated separator after separation in the utility model.

[0034] In the figure: 1. Raw material tank; 2. Condensate preheater; 3. Non-condensing steam preheater; 4. Condensate tank; 5. Heater; 6. Integrated separator; 7. Scrubber; 8. Steam compressor; 9. Condenser;

[0035] Integrated separator: 6a1. Secondary steam outlet; 6a2. Manhole; 6a3. Defoaming section; 6a4. Mother liquor evaporation section; 6a5. Flushing water pipe outlet; 6a6. Ear seat; 6a7. Removable tube baffle; 6a8. Baffle reinforcement ring; 6a9. Concentrated material outlet; 6a10. Wire mesh demister; 6a11. Annular flushing pipe; 6a12. Material inlet; 6a13. Feed bell mouth; 6a14. Material accumulation section;

[0036] 6b1. Inner tube sheet flange; 6b2. Heat exchange section shell; 6b3. Heat transfer tube; 6b4. Upper baffle; 6b5. Lower baffle; 6b6. Heat exchanger bellows; 6b7. Heating steam inlet; 6b8. Outer tube sheet flange; 6b9. Removable tube box head; 6b10. Mounting base; 6b11. Tube box; 6b12. Roller; 6b13. Heat exchange section bracket; 6b14. Condensate outlet.

[0037] B1. Feed pump; B2. Condensate pump; B3. Material circulation pump; B4. Concentrate discharge pump; B5. Washing liquid circulation pump;

[0038] G1. Material feed pipe; G2. Material circulation pipe; G3. Concentrated liquid discharge pipe; G4. Condensate collection pipe; G5. Condensate discharge pipe; G6. Non-condensable gas delivery pipe; G7. Separator secondary steam pipe; G8. Compressed steam pipe; G9. Steam replenishment pipe; G10. Washing liquid circulation pipe; G11. Circulating water delivery pipe. DETAILED DESCRIPTION

[0039] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, the present invention is further described below with reference to specific figures. Obviously, the embodiments described are only a part of the present invention, not all of the embodiments.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0041] like Figure 1As shown, the utility model is suitable for the evaporation concentration system of lithium sulfate purification, which includes a raw material tank 1, a condensate preheater 2, a non-condensing steam preheater 3, a condensate tank 4, a heater 5, an integrated separator 6, a scrubber 7, a steam compressor 8 and a condenser 9. The raw material tank 1 is used to store low-concentration lithium sulfate material. The outlet of the raw material tank 1 is connected to the inlet of the feed pump B1, and the outlet of the feed pump B1 is connected to the cold side inlet of the condensate preheater 2 through the material feed pipe G1. The cold side outlet of the condensate preheater 2 is connected to the cold side inlet of the non-condensing steam preheater 3. The cold side outlet of the non-condensing steam preheater 3 and the outlet pipe of the material circulation pump B3 are connected to the pipe side inlet of the heater 5. The pipe side outlet of the heater 5 is connected to the material inlet 6a12 of the integrated separator 6. The bottom discharge port of the integrated separator 6 is connected to the inlet of the material circulation pump B3 through the material circulation pipe G2.

[0042] The secondary steam outlet 6a1 of the integrated separator 6 is connected to the air inlet of the scrubbing tower 7 through the separator secondary steam pipe G7. The air outlet of the scrubbing tower 7 is connected to the inlet of the steam compressor 8. The outlet of the steam compressor 8 is connected to the shell-side steam inlet of the heater 5 and the steam inlet of the heat exchange section shell 6b2 of the integrated separator 6 through the compressed steam pipe G8. The replenishing port of the compressed steam pipe G8 is connected to the steam replenishing pipe G9.

[0043] The shell-side condensate outlet of the heater 5 is connected to the inlet of the condensate tank 4 through the condensate collection pipe G4, the outlet of the condensate tank 4 is connected to the inlet of the condensate pump B2, the outlet of the condensate pump B2 is connected to the hot side inlet of the condensate preheater 2, and the hot side outlet of the condensate preheater 2 is connected to the condensate reuse system through the condensate external discharge pipe G5.

[0044] The shell-side exhaust port of heater 5 is connected to the hot-side inlet of non-condensing steam preheater 3 via non-condensing gas delivery pipe G6. The hot-side outlet of non-condensing steam preheater 3 is connected to the hot-side inlet of condenser 9, and the hot-side outlet of condenser 9 is connected to the vacuum system. The circulating water delivery pipe G11 is connected to the cold-side inlet of condenser 9. The cold-side outlet of condenser 9 and the outlet circulation pipe of washing liquid circulation pump B5 are connected to the spray port at the top of scrubber tower 7. The drain outlet at the bottom of scrubber tower 7 is connected to the inlet of washing liquid circulation pump B5 via washing liquid circulation pipe G10.

[0045] The lithium sulfate material with a lower concentration is stored in the raw material tank 1, sent out by the feed pump B1, enters the cold side of the condensate preheater 2 through the material feed pipe G1 for primary preheating, and then enters the cold side of the non-condensable gas preheater 3 for secondary preheating, so that the lithium sulfate reaches a near saturation temperature, enters the material circulation pipe G2 of the concentration system and mixes with the circulating liquid, enters the pipe side of the heater 5 for heating, and then enters the integrated separator 6 for evaporation and concentration. The concentrated lithium sulfate is discharged from the bottom of the integrated separator 6 and enters the material circulation pipe G2. The lithium sulfate material circulates in the material circulation pipe G2 through the material circulation pump B3.

[0046] After the concentrated lithium sulfate material reaches the expected concentration, it is discharged from the concentrated liquid discharge pipe G3 and transported to the outside through the concentrated liquid discharge pump B4 to meet various production needs.

[0047] The condensed water generated at the bottom of the shell of the heat exchanger 5 enters the condensed water tank 4 for storage through the condensed water collection pipe G4, and is then sent to the hot side of the condensed water preheater 2 by the condensed water pump B2 as a heat source for the first-level preheating of the feed liquid. The waste heat of the condensed water is recovered and enters the condensed water reuse system through the condensed water discharge pipe G5.

[0048] The condensed water generated at the bottom of the shell side of the separator heating section of the integrated separator 6 is transported outwards through the condensed water collecting pipe G4 and also enters the condensed water tank 4 .

[0049] The non-condensable gas in the shell of heater 5 is discharged through the non-condensable gas conveying pipe G6, first enters the hot side of the non-condensable gas preheater 3 as a heat source for secondary preheating of the liquid, and then enters the hot side of the condenser 9 for heat exchange and cooling, meeting the requirements of micro-negative pressure conveying of non-condensable gas.

[0050] The secondary steam discharged from the top of the integrated separator 6 passes through the separator secondary steam pipe G7 and enters the scrubber 7 for scrubbing and settling, ensuring that the secondary steam entering the steam compressor is dry and clean. The scrubbed secondary steam enters the steam compressor 8 for compression. After compression and heating, the secondary steam passes through the compressed steam pipe G8, one way into the shell side of the heater 5 as a heat source, and the other way into the steam inlet of the integrated separator 6, providing heat for the shell-and-tube heat exchanger. Any heat lost during operation is replenished by the steam replenishment pipe G9, ensuring a heat balance for the evaporation and concentration of the lithium sulfate.

[0051] The scrubbing liquid at the bottom of scrubber 7 enters scrubbing liquid circulation pump B5 through scrubbing liquid circulation pipe G10. This pump returns the scrubbing liquid to the top of scrubber 7 for spraying and circulation, completing the scrubbing liquid circulation process within scrubber 7. The scrubbing liquid consumed during operation is replenished with external circulating water through circulating water delivery pipe G11. During this delivery process, the circulating water flows through the cold side of condenser 9, providing a cooling source for the non-condensable gas.

[0052] like Figures 2 to 4As shown, the middle part of the integrated separator 6 is the mother liquor evaporation section 6a4, and the upper end of the mother liquor evaporation section 6a4 is provided with a defoaming section 6a3 that tapers upward, and a secondary steam outlet 6a1 is provided at the top center of the defoaming section 6a3. A manhole 6a2 is provided on the side wall of the defoaming section 6a3, and a wire mesh demister 6a10 is provided on the inner cross section of the defoaming section 6a3. An annular flushing pipe 6a11 is provided above the wire mesh demister 6a10, and a flushing water pipe port 6a5 is provided on the side wall of the defoaming section 6a3, which communicates with the annular flushing pipe 6a11.

[0053] The lower portion of the mother liquid evaporation section 6a4 is formed into a tapered, tapered barrel that tapers downward. A feed guide tube is located within the lower, middle portion of the barrel. The lower end of the feed guide tube extends from the tapered barrel wall and features a material inlet 6a12. The upper end of the feed guide tube extends toward the axis of the mother liquid evaporation section 6a4 and is equipped with a feed bell mouth 6a13. Lugs 6a6 are located on either side of the barrel in the middle of the mother liquid evaporation section 6a4 to facilitate lifting and transportation.

[0054] The lower end of the conical cylinder is connected to a downwardly extending material accumulation section 6a14, the lower end of which is provided with a concentrated material outlet 6a9. A bypass port is provided on the sidewall of the middle section of the material accumulation section 6a14, and the bypass port flange is connected to a separator heat exchange section extending laterally outward.

[0055] The separator heat exchange section includes a heat exchange section housing 6b2. The inner port of the heat exchange section housing 6b2 is connected to the bypass port flange via an inner tube sheet flange 6b1. The outer port of the heat exchange section housing 6b2 is equipped with an outer tube sheet flange 6b8. Multiple heat transfer tubes 6b3 connect the inner and outer tube sheet flanges 6b1 and 6b8. Multiple baffles are positioned along the length of the heat transfer tubes 6b3. The top of the upper baffle 6b4 is connected to the upper inner wall of the heat exchange section housing 6b2, while the bottom of the lower baffle 6b5 is connected to the lower inner wall of the heat exchange section housing 6b2.

[0056] The distal top of the heat exchange section shell 6b2 is equipped with a heating steam inlet 6b7, the proximal bottom of the heat exchange section shell 6b2 is equipped with a condensate outlet 6b14, and the middle section of the heat exchange section shell 6b2 is equipped with an outwardly protruding heat exchanger corrugated section 6b6. The outer side of the outer tube sheet flange 6b8 is connected to a pipe box 6b11, and the outer port of the pipe box 6b11 is covered with a removable pipe box head 6b9.

[0057] A removable tube-side partition 6a7 is connected to the middle of the end face of the inner tube sheet flange 6b1 facing the material accumulation section 6a14. The base of the removable tube-side partition 6a7 separates the heat transfer tubes 6b3 into two upper and lower groups along the horizontal diameter line of the inner tube sheet flange 6b1. A partition reinforcement ring 6a8 is provided around the middle of the material accumulation section 6a14. The ends of the removable tube-side partition 6a7 fit into the grooves of the partition reinforcement ring 6a8.

[0058] The bottoms of both ends of the heat exchange section shell 6b2 are respectively connected to heat exchange section brackets 6b13, and rollers 6b12 are respectively provided below the heat exchange section brackets 6b13. The bottoms of the rollers 6b12 are supported on the mounting base 6b10.

[0059] The lithium sulfate mother liquor enters through the material inlet 6a12, rises along the feed guide pipe and flows to the center of the separator, flows out from the feed bell mouth 6a13, and completes pressure reduction evaporation in the mother liquor evaporation section 6a4 in the middle of the separator to separate the secondary vapor and concentrated liquid.

[0060] The secondary steam separated from the lithium sulfate solution flows upward into the defoaming section 6a3 at the top of the separator. The wire mesh demister 6a10 removes any entrained liquid droplets and dust, ultimately discharging the steam through the secondary steam outlet 6a1. During production, the evaporation process in the separator can be observed through a manhole 6a2, which allows access to the interior for maintenance. If the wire mesh demister 6a10 becomes contaminated with a significant amount of lithium sulfate, hot water is introduced through the flushing water outlet 6a5 into the annular flushing pipe 6a11 above the wire mesh demister 6a10 to flush the separator's inner walls and the wire mesh demister 6a10.

[0061] After evaporation and concentration, the lithium sulfate enters the material accumulation section 6a14 at the bottom of the separator. Blocked by removable tube baffles 6a7, it enters the heat transfer tubes 6b3 in the upper heat exchange section for heating. After heating in the heat transfer tubes, the lithium sulfate enters the pipe box 6b11 and flows to the heat transfer tubes 6b3 in the lower heat exchange section for secondary heating. After exiting the inner tube sheet flange 6b1, it enters the bottom of the material accumulation section 6a14 and is ultimately discharged through the concentrated material outlet 6a9.

[0062] Heating steam enters the separator's heating section's shell side through heating steam inlet 6b7. It then passes through multiple upper and lower baffles 6b4 and 6b5, where it is deflected. After sufficient heat exchange with the heat transfer tubes, it becomes condensed water and is discharged through condensate outlet 6b14 into condensate tank 4. To prevent deformation of the separator's heat exchange section due to thermal stress, a heat exchanger corrugated section 6b6 is designed within the heat exchange section shell 6b2 to eliminate thermal stress during the heat exchange process.

[0063] The separator heating section and the external heater 5 are heated together, which can improve the evaporation efficiency, eliminate the need to set a second heater on the downward-flowing circulation pipe, and reduce the overall height of the equipment.

[0064] Taking into account the continuous operation of the device, if the upstream lithium sulfate concentration changes and the evaporation amount decreases, the removable tube partition 6a7, the inner tube sheet flange 6b1, the outer tube sheet flange 6b8 and the removable tube box head 6b9 are disassembled, and the integrated separator heat exchange section is quickly disassembled by the roller 6b12 at the bottom of the separator heat exchange section, and the entire system is changed from a dual heater to a single heater, which can be adjusted according to different feed concentration and discharge concentration requirements.

[0065] The above description is only a preferred embodiment of the present invention, which shows and describes the basic principles, main features and advantages of the present invention, but does not limit the scope of patent protection of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. In addition to the above embodiments, the present invention may have other implementation methods without departing from the spirit and scope of the present invention. The present invention may also have various changes and improvements, and all technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention. The scope of protection required by the present invention is defined by the attached claims and their equivalents. Technical features not described in the present invention can be achieved by or using existing technologies, and will not be described here.

Claims

1. An evaporation and concentration system suitable for purification of lithium sulfate, comprising a raw material tank, characterized in that: The outlet of the raw material tank is connected to the inlet of the feed pump, the outlet of the feed pump is connected to the cold side inlet of the condensate preheater, the cold side outlet of the condensate preheater is connected to the cold side inlet of the non-condensing steam preheater, the cold side outlet of the non-condensing steam preheater and the outlet pipe of the material circulation pump are connected to the tube side inlet of the heater, the tube side outlet of the heater is connected to the material inlet of the integrated separator, and the bottom discharge port of the integrated separator is connected to the inlet of the material circulation pump; The secondary steam outlet of the integrated separator is connected to the air inlet of the scrubber, the air outlet of the scrubber is connected to the inlet of the steam compressor, and the outlet of the steam compressor is connected to the shell-side steam inlet of the heater through a compressed steam pipe; The shell-side condensate outlet of the heater is connected to the inlet of the condensate tank, and the outlet of the condensate tank is connected to the hot side inlet of the condensate preheater through a condensate pump; The shell side exhaust port of the heater is connected to the hot side inlet of the non-condensing steam preheater through a non-condensing gas conveying pipe, the hot side outlet of the non-condensing steam preheater is connected to the hot side inlet of the condenser, and the hot side outlet of the condenser is connected to the vacuum system.

2. The evaporation concentration system suitable for purification of lithium sulfate according to claim 1, characterized in that: The circulating water delivery pipe is connected to the cold side inlet of the condenser, the cold side outlet of the condenser and the outlet circulation pipe of the washing liquid circulation pump are connected to the spray port on the upper part of the washing tower, and the drain outlet at the bottom of the washing tower is connected to the inlet of the washing liquid circulation pump through the washing liquid circulation pipe.

3. The evaporation concentration system suitable for purification of lithium sulfate according to claim 1 or 2, characterized in that: The middle part of the integrated separator is a mother liquid evaporation section, the upper end of the mother liquid evaporation section is provided with a defoaming section that tapers upward, and the top center of the defoaming section is provided with a secondary steam outlet; the lower part of the barrel of the mother liquid evaporation section is provided with a tapered cylinder that gradually narrows downward, and the middle and lower inner cavity of the mother liquid evaporation section is provided with a feed guide pipe, the lower end of the feed guide pipe extends from the tapered wall of the tapered cylinder and is provided with a material inlet, and the upper end of the feed guide pipe extends toward the axis of the mother liquid evaporation section and is provided with a feed bell mouth; The lower end of the conical cylinder is connected to a material accumulation section extending downward, and a concentrated material outlet is provided at the lower end of the material accumulation section; a bypass port is provided on the side wall of the middle section of the material accumulation section, and a separator heat exchange section extending laterally outward is connected to the bypass port flange; The separator heat exchange section includes a heat exchange section shell, the inner port of the heat exchange section shell is connected to the bypass port flange through the inner tube sheet flange, the outer port of the heat exchange section shell is provided with an outer tube sheet flange, the inner tube sheet flange and the outer tube sheet flange are connected by multiple heat transfer tubes, and the outer side of the outer tube sheet flange is connected to a pipe box; A removable tube-side partition is provided on the middle cross section of the material accumulation section. The root of the removable tube-side partition is connected to the middle diameter line of the inner end tube sheet flange to separate the heat transfer tubes into two groups, upper and lower.

4. The evaporation concentration system suitable for purification of lithium sulfate according to claim 3, characterized in that: A partition reinforcing ring is provided on the circumference of the middle section of the material accumulation section, and the end of the detachable pipe-side partition is embedded in the groove of the partition reinforcing ring.

5. The evaporation concentration system suitable for purification of lithium sulfate according to claim 3, characterized in that: A heating steam inlet is provided at the distal top of the heat exchange section shell, and the heating steam inlet is connected to the compression steam pipe. A condensed water outlet is provided at the proximal bottom of the heat exchange section shell.

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