A lithium sulfate solution concentration device

Abstract

This invention provides a lithium sulfate solution concentration device, comprising: a first evaporator; a first evaporator heater, the inlet end of which is connected to the first evaporator via a first pipeline, and the outlet end of which is connected back to the first evaporator; a first circulation pump located on the first pipeline; a feed pipe connected to the first pipeline; a second evaporator; a second evaporator heater, the inlet end of which is connected to the second evaporator via a second pipeline, and the outlet end of which is connected back to the second evaporator; a second circulation pump located on the second pipeline; a discharge pipe connected to the drain port of the second evaporator; the first evaporator connected to the second evaporator heater; and the drain ports of the first and second evaporators connected via a transfer pipe, wherein the connection end of the transfer pipe to the drain port of the first evaporator is higher than the other end. By setting the height difference between the two ends of the transfer pipe, the transfer pump is eliminated, avoiding problems such as easy clogging, easy wear, and difficult maintenance that exist during the use of the transfer pump, thus improving production efficiency and saving operating energy and equipment costs.

Description

Technical Field

[0001] This utility model belongs to the field of concentration equipment technology, specifically relating to a lithium sulfate solution concentration device. Background Technology

[0002] In the sulfuric acid process for lithium extraction from ore, a relatively pure dilute lithium sulfate solution is obtained. This solution is mainly used for subsequent production of lithium hydroxide or lithium carbonate. To reduce energy consumption in subsequent production processes, this dilute lithium sulfate solution needs to be concentrated first. Currently, the MVR (mechanical vapor recompression) evaporation process is mainly used for concentrating the dilute lithium sulfate solution, which has advantages such as low energy consumption and high production efficiency. However, in the existing MVR evaporation system, due to the increased concentration of lithium sulfate solution during concentration, crystallization easily occurs in the system. Especially during solution transfer, the high concentration and crystallized material easily cause wear on the transfer pump, resulting in a high failure rate, high maintenance costs, and troublesome repairs, thus affecting normal production. Utility Model Content

[0003] In view of the problems existing in the prior art, the present invention aims to provide a lithium sulfate solution concentration device. In this device, the solution is directly transferred by setting the height difference between the two ends of the transfer pipe, eliminating the need for a transfer pump. This avoids the problems of easy clogging, easy wear, difficult maintenance, and high maintenance frequency that exist during the use of the transfer pump, effectively improving production efficiency and saving operating energy consumption and equipment costs.

[0004] The technical solution adopted in this utility model is as follows:

[0005] A lithium sulfate solution concentration apparatus, comprising:

[0006] First evaporator;

[0007] The first evaporator heater has its material heating channel inlet end connected to the bottom drain port of the first evaporator via a first pipeline, and its material heating channel outlet end connected back to the first evaporator.

[0008] A first circulation pump is installed on the first pipeline to pump the solution in the first evaporator to the first evaporator heater;

[0009] A feed pipe, connected to the first pipeline, is used to provide a dilute lithium sulfate solution to be concentrated;

[0010] Second evaporator;

[0011] The second evaporator heater has its material heating channel inlet end connected to the bottom drain port of the second evaporator via a second pipeline, and its material heating channel outlet end connected back to the second evaporator.

[0012] The second circulation pump, installed on the second pipeline, is used to pump the solution in the second evaporator to the second evaporator heater;

[0013] The discharge pipe is connected to the drain port at the bottom of the second evaporator;

[0014] in,

[0015] The gas-liquid outlet at the top of the first evaporator is connected via a pipeline to the inlet end of the steam condensation channel of the second evaporator heater;

[0016] The bottom drain of the first evaporator is directly connected to the bottom drain of the second evaporator via a transfer pipe. The connection point between the transfer pipe and the bottom drain of the first evaporator is higher than the connection point between the transfer pipe and the bottom drain of the second evaporator.

[0017] In one embodiment of this application, a storage tank is further included, which is directly connected to the bottom drain port of the second evaporator via the discharge pipe, and the connection point between the discharge pipe and the bottom drain port of the second evaporator is higher than the connection point between the discharge pipe and the storage tank.

[0018] In one embodiment of this application, the gas-liquid outlet at the top of the second evaporator is also connected via a pipeline to the inlet end of the steam condensation channel of the second evaporator heater.

[0019] In one embodiment of this application, a first gas-liquid separator and a second gas-liquid separator are further included; the inlet end of the first gas-liquid separator is connected to the gas-liquid outlet at the top of the first evaporator, the liquid outlet of the first gas-liquid separator is connected back to the first evaporator via a pipeline, and the gas outlet of the first gas-liquid separator is connected to the inlet end of the steam condensation channel of the second evaporator via a pipeline; the inlet end of the second gas-liquid separator is connected to the gas-liquid outlet at the top of the second evaporator, the liquid outlet of the second gas-liquid separator is connected back to the second evaporator via a pipeline, and the gas outlet of the second gas-liquid separator is connected to the inlet end of the steam condensation channel of the second evaporator via a pipeline.

[0020] In one embodiment of this application, a compressor is further included, wherein the inlet end of the compressor is connected to the outlet of the first gas-liquid separator and the second gas-liquid separator via a third pipeline; and the outlet end of the compressor is connected to the inlet end of the steam condensation channel of the second evaporator heater.

[0021] In one embodiment of this application, a liquid collection tank is further included, the inlet of which is connected via a pipeline to the third pipeline and the compressor outlet.

[0022] In one embodiment of this application, the first evaporator is installed at a higher position than the second evaporator, the storage tank is installed at a lower position than the second evaporator, and both the transfer pipe and the discharge pipe are straight pipes arranged at an incline.

[0023] In one embodiment of this application, the diameter of the transfer tube is at least three times the diameter of the feed tube.

[0024] In one embodiment of this application, a non-condensable gas heat exchanger and a condensate heat exchanger are sequentially disposed on the feed pipe. The inlet of the heat medium channel of the non-condensable gas heat exchanger is connected to the non-condensable gas outlet of the first evaporator and the second evaporator via a pipeline. The inlet of the heat medium channel of the condensate heat exchanger is connected to the condensate outlet of the first evaporator and the second evaporator via a pipeline.

[0025] In one embodiment of this application, a condensate tank and a condensate pump are further included. The inlet end of the condensate tank is connected via a pipeline to the condensate outlet of the first evaporator and the second evaporator. The inlet end of the condensate pump is connected to the lower outlet of the condensate tank, and the outlet end of the condensate pump is connected to the inlet of the heat medium channel of the condensate heat exchanger.

[0026] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0027] 1. The lithium sulfate solution concentration device of this application directly transfers the solution by setting the height difference between the two ends of the transfer pipe, eliminating the need for a transfer pump. This avoids the problems of easy clogging, easy wear, difficult maintenance, and high maintenance frequency that exist during the use of the transfer pump, effectively improving production efficiency and saving operating energy consumption and equipment costs.

[0028] 2. The second evaporator is positioned higher than the storage tank, and the material is discharged directly through the discharge pipe, eliminating the need for a discharge pump. This avoids problems such as easy clogging, easy wear, difficult maintenance, and high maintenance frequency that occur with discharge pumps during use, effectively improving production efficiency and saving operating energy consumption and equipment costs.

[0029] 3. A non-condensable gas heat exchanger and a condensate heat exchanger are installed on the feed pipe. The non-condensable gas and condensate are used to preheat the dilute lithium sulfate solution to be concentrated twice, which fully recovers the heat energy of the non-condensable gas and condensate and ensures that the dilute lithium sulfate solution to be concentrated is fully preheated. This can avoid large temperature fluctuations in the concentration system after entering the concentration system and quickly reach the evaporation temperature, thereby improving the system's operational stability and concentration efficiency. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the lithium sulfate solution concentration device of this utility model.

[0032] Figure label:

[0033] 1. First evaporator; 11. First pipeline; 12. Feed pipe; 13. Transfer pipe; 14. First gas-liquid separator;

[0034] 2. First evaporator heater;

[0035] 3. First circulating pump;

[0036] 4. Second evaporator; 41. Second pipeline; 42. Discharge pipe; 43. Second gas-liquid separator

[0037] 5. Second evaporator heater; 51. Compressor; 511. Third pipeline; 512. Liquid collection tank;

[0038] 6. Second circulation pump;

[0039] 7. Storage tank;

[0040] 8. Non-condensable gas heat exchanger;

[0041] 9. Condensate heat exchanger; 91. Condensate tank; 92. Condensate pump. Detailed Implementation

[0042] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0043] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this utility model and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0044] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0045] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0046] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0047] The following disclosure provides many different embodiments or examples for implementing various structures of this invention. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this invention.

[0048] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0049] This utility model provides a lithium sulfate solution concentration device, such as... Figure 1 As shown, the lithium sulfate solution concentration device includes a first evaporator 1, a first evaporation heater 2 and a first circulation pump 3 forming a first heating and evaporation cycle, a second evaporator 4, a second evaporation heater 5 and a second circulation pump 6 forming a second heating and evaporation cycle, as well as a feed pipe 12, a transfer pipe 13 and a discharge pipe 42, etc.

[0050] The first evaporator 1 is the part in the first heating and evaporation cycle where the solution is heated and evaporated.

[0051] The first evaporator heater 5 is a heat exchange heater, which has a material heating channel and a steam condensation channel. The inlet end of its material heating channel is connected to the drain port at the bottom of the first evaporator 1 via the first pipeline 11, and the outlet end of its material heating channel is connected back to the middle of the first evaporator 1 via a pipeline.

[0052] The first circulation pump 3 is installed on the first pipeline 11. Its inlet end is connected to the drain port at the bottom of the first evaporator 1, and its outlet end is connected to the inlet end of the material heating channel of the first evaporator heater 2. The first circulation pump 3 is used to pump the solution in the first evaporator 1 into the first evaporator heater 2 for heating. The first evaporator 1, the first circulation pump 3, and the first evaporator heater 2 constitute the first heating evaporation cycle.

[0053] The feed pipe 12 is connected to the first pipeline 11 to provide the dilute lithium sulfate solution to be concentrated and to send the dilute lithium sulfate solution to be concentrated into the first heating evaporation cycle.

[0054] The second evaporator 4 is the part in the second heating and evaporation cycle where the solution is heated and evaporated.

[0055] The second evaporator heater 5 is a heat exchange heater, which has a material heating channel and a steam condensation channel. The inlet end of its material heating channel is connected to the drain port at the bottom of the second evaporator 4 via the second pipeline 41, and the outlet end of its material heating channel is connected back to the middle of the second evaporator 4 via a pipeline.

[0056] The second circulation pump 6 is installed on the second pipeline 41. Its inlet end is connected to the drain port at the bottom of the second evaporator 4, and its outlet end is connected to the inlet end of the material heating channel of the second evaporator heater 5. The second circulation pump 6 is used to pump the solution in the second evaporator 4 into the second evaporator heater 5 for heating. The second evaporator 4, the second circulation pump 6, and the second evaporator heater 5 constitute the second heating evaporation cycle.

[0057] The discharge pipe 42 is connected to the bottom drain port of the second evaporator 4 or the second pipeline 41 to discharge the concentrated lithium sulfate solution.

[0058] The gas-liquid outlet at the top of the first evaporator 1 is connected to the inlet of the steam condensation channel of the second evaporator heater 5 via a pipeline. The steam generated by the first heating evaporation cycle is heated by the solution in the second heating evaporation cycle, making full use of thermal energy, effectively reducing the waste of thermal energy emissions, and saving energy consumption.

[0059] A transfer pipe 13 is installed at the bottom drain port of the first evaporator 1 or on the first pipe 11 at the bottom drain port, directly connecting to the bottom drain port of the second evaporator 4 or on the second pipe 41 at the bottom drain port. The connection point of the transfer pipe 13 to the bottom drain port / first pipe 11 of the first evaporator 1 is higher than the connection point of the transfer pipe 13 to the bottom drain port / second pipe 41 of the second evaporator 4. The solution in the first evaporator 1 / first heating evaporation cycle can be directly discharged to the second evaporator 4 / second heating evaporation cycle under gravity. This achieves continuous concentration and transfer of the solution.

[0060] Preferably, the installation position of the first evaporator 1 is higher than that of the second evaporator 4, that is, the bottom drain port of the first evaporator 1 is higher than the bottom drain port of the second evaporator 4. The transfer pipe 13 is set as an inclined straight pipe to ensure that the solution evaporated in the first evaporator 1 flows smoothly to the second evaporator 4 under gravity. More preferably, when the transfer pipe 13 is a straight pipe, the height difference between the two ends should be controlled at more than 30 cm, and / or the inclination angle should be 5°~15°, which can effectively ensure the smooth and safe discharge of the solution and avoid excessive flow rate or poor discharge.

[0061] The diameter (inner diameter) of the preferred transfer pipe 13 is at least three times that of the feed pipe 12. Using a larger transfer pipe 13 can effectively ensure smooth automatic material transfer and ensure stable and reliable system operation.

[0062] Furthermore, it also includes a storage tank 7, which is directly connected to the drain port at the bottom of the second evaporator 4 or the second pipeline 41 via a discharge pipe 42. The horizontal height of the connection between the discharge pipe 42 and the drain port at the bottom of the second evaporator 4 or the connection between the discharge pipe 42 and the second pipeline 41 is higher than the horizontal height of the connection between the discharge pipe 42 and the storage tank 7, that is, the solution discharged from the bottom drain port of the second evaporator 4 can be directly discharged into the storage tank 7 under the action of gravity.

[0063] Preferably, the installation position of the storage tank 7 is lower than that of the second evaporator 4, so that the bottom drain port of the second evaporator 4 is at a higher level than the top of the storage tank 7. The discharge pipe 42 is set as an inclined straight pipe to ensure that the solution evaporated in the second evaporator 4 flows smoothly into the storage tank 7 under gravity. More preferably, when the discharge pipe 42 is a straight pipe, the height difference between the two ends should be controlled at more than 30 cm, and / or the inclination angle should be 5°~15°, which can effectively ensure the smooth and safe discharge of the solution and avoid excessive flow rate or poor discharge.

[0064] In one embodiment, the gas-liquid outlet at the top of the second evaporator 4 is also connected via a pipeline to the inlet of the steam condensation channel of the second evaporator heater 5, so as to reuse the excess steam heat generated by the second heating evaporation cycle, make full use of thermal energy, reduce heat energy emission waste, and save energy consumption.

[0065] It also includes a first gas-liquid separator 14 and a second gas-liquid separator 43. The inlet end of the first gas-liquid separator 14 is connected to the gas-liquid outlet at the top of the first evaporator 1, and the liquid outlet at the bottom of the first gas-liquid separator 14 is connected back to the top of the first evaporator 1 via a pipeline. The gas outlet at the top of the first gas-liquid separator 14 is connected to the inlet end of the steam condensation channel of the second evaporator heater 5 via a pipeline. The inlet end of the second gas-liquid separator 43 is connected to the gas-liquid outlet at the top of the second evaporator 4, and the liquid outlet at the bottom of the second gas-liquid separator 43 is connected back to the top of the second evaporator 4 via a pipeline. The gas outlet at the top of the second gas-liquid separator 43 is connected to the inlet end of the steam condensation channel of the second evaporator heater 5 via a pipeline. That is, the steam from both the first evaporator 1 and the second evaporator 4 undergoes gas-liquid separation treatment by the gas-liquid separators. The steam is discharged to the second evaporator heater 5 for heat energy recovery, and the liquid is separated and returned to the heating evaporation cycle for concentration, reducing the loss of lithium sulfate solution.

[0066] Furthermore, it also includes a compressor 51, the inlet of which is connected via a third pipe 511 to the outlet of the first gas-liquid separator 14 and the second gas-liquid separator 43; the outlet of the compressor 51 is connected to the inlet of the steam condensation channel of the second evaporator heater 5. That is, the steam separated by the first gas-liquid separator 14 and the second gas-liquid separator 43 is compressed by the compressor 51 and then enters the steam condensation channel of the second evaporator heater 5 for heating. The compressor 51 ensures that the second evaporator heater 5 achieves the required heat exchange effect.

[0067] Preferably, a liquid collection tank 512 is also provided. The inlet of the liquid collection tank 512 is connected via a pipeline to a third pipeline 511 before the inlet of the compressor 51, and via a pipeline to the outlet end of the compressor 51. The liquid in the third pipeline 511 and the liquid generated during the compression process of the compressor 51 can be collected and stored.

[0068] In one embodiment, a non-condensable gas heat exchanger 8 and a condensate heat exchanger 9 are sequentially arranged on the feed pipe 12. The inlet of the heat medium channel of the non-condensable gas heat exchanger 8 is connected via a pipeline to the non-condensable gas outlet of the first evaporator heater 2 and the second evaporator heater 5; the inlet of the heat medium channel of the condensate heat exchanger 9 is connected via a pipeline to the condensate outlet of the first evaporator heater 2 and the second evaporator heater 5. By using the waste heat from the heat exchange between the first evaporator heater 2 and the second evaporator heater 5, the raw material liquid (the dilute lithium sulfate solution to be concentrated) is preheated twice. This allows the raw material liquid to quickly reach the evaporation temperature after entering the first heating evaporation cycle, avoiding large temperature fluctuations in the first heating evaporation cycle system, while simultaneously fully recovering waste heat and reducing energy consumption.

[0069] Furthermore, a condensate tank 91 and a condensate pump 92 are also provided. The inlet end of the condensate tank 91 is connected via a pipeline to the condensate outlet of the first evaporator heater 2 and the second evaporator heater 5. The inlet end of the condensate pump 92 is connected to the lower outlet of the condensate tank 91, and the outlet end of the condensate pump 92 is connected to the inlet of the heat medium channel of the condensate heat exchanger 9. The condensate tank 91 is provided to collect and store the condensate discharged from the first evaporator heater 2 and the second evaporator heater 5, and to provide a stable condensate flow for the condensate pump 92 and the condensate heat exchanger 9. The condensate pump 92 is provided to provide a stable condensate flow required for heat exchange in the condensate heat exchanger 9 and to control the flow rate, ensuring that the required heat exchange effect is achieved.

Claims

1. A lithium sulfate solution concentration device, characterized by, include: First evaporator; The first evaporator heater has its material heating channel inlet end connected to the bottom drain port of the first evaporator via a first pipeline, and its material heating channel outlet end connected back to the first evaporator. A first circulation pump is installed on the first pipeline to pump the solution in the first evaporator to the first evaporator heater; A feed pipe, connected to the first pipeline, is used to provide a dilute lithium sulfate solution to be concentrated; Second evaporator; The second evaporator heater has its material heating channel inlet end connected to the bottom drain port of the second evaporator via a second pipeline, and its material heating channel outlet end connected back to the second evaporator. The second circulation pump, installed on the second pipeline, is used to pump the solution in the second evaporator to the second evaporator heater; The discharge pipe is connected to the drain port at the bottom of the second evaporator; in, The gas-liquid outlet at the top of the first evaporator is connected via a pipeline to the inlet end of the steam condensation channel of the second evaporator heater; The bottom drain of the first evaporator is directly connected to the bottom drain of the second evaporator via a transfer pipe. The connection point between the transfer pipe and the bottom drain of the first evaporator is higher than the connection point between the transfer pipe and the bottom drain of the second evaporator.

2. The lithium sulfate solution concentration device according to claim 1, characterized by It also includes a storage tank, which is directly connected to the bottom drain port of the second evaporator via the discharge pipe. The connection point between the discharge pipe and the bottom drain port of the second evaporator is higher than the connection point between the discharge pipe and the storage tank.

3. The lithium sulfate solution concentration device according to claim 1 or 2, characterized by The gas-liquid outlet at the top of the second evaporator is also connected via a pipeline to the inlet end of the steam condensation channel of the second evaporator heater.

4. The lithium sulfate solution concentration device according to claim 3, characterized by It also includes a first gas-liquid separator and a second gas-liquid separator; the inlet end of the first gas-liquid separator is connected to the gas-liquid outlet at the top of the first evaporator, the liquid outlet of the first gas-liquid separator is connected back to the first evaporator via a pipeline, and the gas outlet of the first gas-liquid separator is connected to the inlet end of the steam condensation channel of the second evaporator via a pipeline; the inlet end of the second gas-liquid separator is connected to the gas-liquid outlet at the top of the second evaporator, the liquid outlet of the second gas-liquid separator is connected back to the second evaporator via a pipeline, and the gas outlet of the second gas-liquid separator is connected to the inlet end of the steam condensation channel of the second evaporator via a pipeline.

5. The lithium sulfate solution concentration device of claim 4, wherein, It also includes a compressor, the inlet of which is connected to the outlet of the first gas-liquid separator and the second gas-liquid separator via a third pipeline; the outlet of the compressor is connected to the inlet of the steam condensation channel of the second evaporator heater.

6. The lithium sulfate solution concentration apparatus according to claim 5, characterized in that, It also includes a liquid collection tank, the inlet of which is connected via a pipeline to the third pipeline and the compressor outlet.

7. The lithium sulfate solution concentration device of claim 2, wherein The first evaporator is installed at a higher position than the second evaporator, the storage tank is installed at a lower position than the second evaporator, and both the transfer pipe and the discharge pipe are straight pipes installed at an incline.

8. The lithium sulfate solution concentration device of claim 7, wherein, The diameter of the transfer pipe is at least three times the diameter of the feed pipe.

9. The lithium sulfate solution concentration device according to claim 1 or 8, characterized by The non-condensable gas heat exchanger is connected with the non-condensable gas outlet of the first evaporation heater and the second evaporation heater through a pipeline at the heat medium passage inlet.

10. The lithium sulfate solution concentration device of claim 9, wherein, The condensate tank is connected with the condensate water outlet of the first evaporation heater and the second evaporation heater through a pipeline at the inlet end; the inlet end of the condensate pump is connected with the lower outlet of the condensate tank, and the outlet end of the condensate pump is connected with the heat medium passage inlet of the condensate water heat exchanger.

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