Pre-decarbonization device based on sodium bicarbonate solution evaporation system

Abstract

The present application relates to liquid degassing and chemical separation technical field, specifically, it relates to front decarburization device based on sodium bicarbonate solution evaporation system, it includes tower body, multilayer float valve tray arranged in the inside of tower body, and gas outlet and material inlet arranged at the top of tower body, also includes sieve plate and flow guide mechanism;The sieve plate is below the float valve tray plate, and the top of sieve plate is equipped with partition;The partition separates the space between float valve tray plate and sieve plate into at least two independent airflow chambers, and the bottom of each airflow chamber is communicated with the inside of tower body;The first airflow chamber and the second airflow chamber which are independent and communicated with the inside of tower body are arranged below the float valve plate body, when the first airflow chamber or the second airflow chamber is switched to the disconnected state, loses the rising gas in its inside, the traction arm arranged in the airflow chamber is pulled down by chain to the corresponding float valve, so as to drive the stuck float valve to reset forcibly.

Description

Technical Field

[0001] This invention relates to the field of liquid degassing and chemical separation technology, and more specifically, to a pre-decarbonization device for a sodium bicarbonate solution evaporation system. Background Technology

[0002] In processes such as clean production of sodium carbonate or carbon dioxide capture and resource utilization, process solutions rich in sodium bicarbonate are often generated. Before being sent to the evaporation system for concentration, this solution must undergo pre-decarbonization treatment. The core purpose is to utilize the poor thermal stability of sodium bicarbonate, by heating it to pre-decompose it into stable sodium carbonate, water, and carbon dioxide, and then efficiently separate and discharge the carbon dioxide gas from the liquid phase.

[0003] If this step is omitted, after the solution enters the evaporator, the large amount of carbon dioxide bubbles generated by the violent decomposition at high temperature will adhere to the heat exchange tube wall and form a gas film, which will seriously hinder heat transfer.

[0004] Currently, the common industrial equipment for realizing this pre-decarbonization process is a vertical thermal decomposition degassing tower with built-in floating valve trays. Its typical process is as follows: cold sodium bicarbonate solution enters the floating valve tray area evenly from the top of the tower through a liquid distributor, flows laterally on each tray, and comes into contact with the high-temperature gas rising through the floating valves, thus completing the decomposition of sodium bicarbonate. The generated carbon dioxide and water vapor are discharged upwards.

[0005] However, the unit faces a significant problem during operation. The floating valves on the valve tray need to continuously move up and down to adjust their opening according to changes in the gas phase load. However, under the harsh conditions of high temperature, high alkali, and easy precipitation of sodium carbonate crystals in the decarbonation tower, the floating valves occasionally become stuck. Once the floating valve is stuck in the open or semi-open position, the liquid on the tray loses its effective gas support and liquid seal, leaking directly from the tray opening to the lower layer, resulting in leakage. This abnormal leakage leads to a shortened residence time of all subsequent liquids on the tray, causing sodium bicarbonate to flow down short-circuit without sufficient thermal decomposition, thus affecting the decarbonation efficiency. Summary of the Invention

[0006] The purpose of this invention is to provide a pre-decarbonization device for a sodium bicarbonate solution evaporation system. This device solves the problem mentioned in the background art, namely, the problem of continuous abnormal liquid leakage when the existing float valve cannot be reset properly. This is achieved by setting independent airflow chambers separated by baffles below the float valve tray and using a flow guiding mechanism to control the alternating communication between each airflow chamber and the inside of the tower body. In conjunction with the traction component set in the airflow chamber, a downward forced pulling force is applied to the stuck float valve.

[0007] To achieve the above objectives, the pre-decarbonization device for the sodium bicarbonate solution evaporation system includes a tower body, a multi-layer floating valve tray disposed inside the tower body, and a gas outlet and a material inlet disposed at the top of the tower body, as well as a sieve plate and a flow guiding mechanism. The sieve plate is located below the floating valve tower plate, and a partition is provided on the top of the sieve plate; The baffle plate divides the space between the floating valve tray and the sieve plate into at least two independent airflow chambers, and the bottom of each airflow chamber is connected to the interior of the tower body. The flow guiding mechanism is movably installed at the connection between the airflow chamber and the tower body, and is used to control the alternating connection between multiple airflow chambers and the interior of the tower body through a movable manner; The airflow chamber is equipped with a traction component that is flexibly connected to the float valve. When the airflow chamber is disconnected from the inside of the tower, the traction component applies a downward pulling force to the float valve to reset the stuck float valve.

[0008] In the above technical solution, the flow guiding mechanism intermittently and alternately blocks the connecting ports at the bottom of each airflow chamber, causing each airflow chamber to periodically and alternately connect with the interior of the tower. When an airflow chamber is blocked by the flow guiding mechanism and disconnected from the interior of the tower, no more rising gas enters that airflow chamber, and the airflow driving force disappears. At this time, the traction component installed in that airflow chamber immediately applies a downward pulling force to the corresponding float valve, causing the float valve that cannot be reset normally to reset downward. At the same time, the remaining unblocked airflow chambers remain connected to the interior of the tower, and rising gas continues to enter the upper float valve tray through the airflow chamber on that side, driving the float valve in the corresponding area to work normally and maintaining the continuous gas-liquid contact and thermal decomposition reaction. Through the alternating switching of the airflow chambers, the float valves in each area can be periodically forced to reset.

[0009] The partition is a straight-line structure and is vertically fixed to the middle of the upper surface of the screen plate, dividing the space above the screen plate into a first airflow chamber and a second airflow chamber.

[0010] Based on this, the flow guiding mechanism includes a baffle whose top surface is attached to the bottom surface of the screen plate body, and a bushing is provided on one side of the baffle. The bushing is rotatably sleeved on the outer ring of the bottom fixed shaft of the screen plate body. It also includes a driving component disposed on the outer wall of the tower body, which is connected to a bushing for driving the baffle to rotate.

[0011] Its rotation mode is as follows: the baffle rotates intermittently at preset intervals, and when it stops rotating each time, the baffle is located below the first airflow chamber or the second airflow chamber.

[0012] Based on this, the traction component includes a traction arm and a flexible connector disposed at the end of the traction arm; The flexible connector is a chain made of metal material, with one end of the chain fixedly connected to the end of the traction arm and the other end fixedly connected to the float valve.

[0013] The structure of the traction arm includes the following two types: Structure 1: One end of the traction arm is located in the first airflow chamber, and the other end rotates through the partition and extends into the second airflow chamber. Both ends of the traction arm are connected to chains so that when the float valve corresponding to one airflow chamber is pushed by gas, it drives the float valve corresponding to the other airflow chamber to move down and reset.

[0014] Structure 2: The traction arm is rotatably mounted on both sides of the partition, and a wind-facing plate is fixedly mounted on the side wall. When there is no airflow passing through the airflow chamber, the traction arm drives the float valve to reset by its own weight.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: In this pre-decarbonization device for a sodium bicarbonate solution evaporation system, two independent airflow chambers, a first airflow chamber and a second airflow chamber, are installed below the float valve plate and communicate with the interior of the tower. The alternating communication between these chambers reduces the likelihood of the float valve getting stuck during high-frequency sliding. When either the first or second airflow chamber is switched to the off state and loses its upward gas flow, a traction arm located within that chamber applies a downward pulling force to the corresponding float valve via a chain. This forces the stuck float valve to reset, preventing subsequent material from continuously leaking to the lower layers through the stuck valve.

[0016] Furthermore, the first and second airflow chambers below the float valve plate are enclosed by a screen plate. This screen plate serves two purposes: firstly, it creates an independent airflow space below the float valve plate, providing a structural basis for the alternating air supply to the chambers; secondly, when the float valve becomes stuck, causing abnormal leakage of some liquid through the valve orifice, the screen plate can collect and temporarily store the leaking liquid. As the rising gas passes through the screen holes, it continues to heat this portion of liquid, promoting its thermal decomposition. This prevents the leakage from disturbing the liquid temperature within the lower float valve plate, thus improving the stability of the temperature field and decarbonization efficiency throughout the tower. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram showing the positions of the float valve plate and the screen plate of the present invention; Figure 3 This is a schematic diagram of the structure of the floating valve tray of the present invention; Figure 4 This is a schematic diagram of the sieve plate of the present invention; Figure 5 This is a schematic diagram of the structure of the traction arm of the present invention. Figure 1 ; Figure 6 This is a schematic diagram of the structure of the traction arm of the present invention. Figure 2 ; Figure 7 This is a schematic diagram of the flow guiding mechanism of the present invention; Figure 8 This is a schematic diagram of the windward plate of the present invention; Figure 9 This is a schematic diagram of the working state of the traction arm of the present invention.

[0018] The meanings of the labels in the diagram are as follows: 100. Tower body; 101. Gas outlet; 102. Material inlet; 103. Fan; 104. Heat exchanger; 105. Base; 110. Float valve plate; 111. Valve hole; 112. Float valve; 113. Baffle plate; 114. Overflow weir; 115. Guide plate; 120. Screen plate; 121. Screen hole; 122. Through port; 123. Side plate; 130. Baffle plate; 131. First airflow chamber; 132. Second airflow chamber; 140. Traction arm; 141. Chain; 142. Shaft; 143. Windward plate; 150. Flow guiding mechanism; 151. Baffle; 152. Bushing; 153. Transmission rod; 154. Motor. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not 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 invention.

[0021] Furthermore, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0022] Sodium bicarbonate solution has a low concentration, high water content, and poor thermal stability, making it unsuitable for direct concentration in an evaporation system. Therefore, it must first undergo a pre-decarbonation treatment before entering the evaporation system. This device converts the unstable sodium bicarbonate in the solution into stable sodium carbonate, while simultaneously separating and removing the carbon dioxide gas produced during decomposition from the liquid phase. The decarbonated sodium carbonate solution is then stable and fed into the subsequent evaporation system, where heating and evaporation remove excess water, ultimately yielding a high-concentration sodium carbonate solution or solid product.

[0023] Structurally, refer to Figure 1 The pre-decarbonization unit is mainly composed of a vertical tower body 100. The tower body 100 has multiple layers of floating valve trays inside, with a gas outlet 101 at the top and a material inlet 102 located below the gas outlet 101. The material inlet 102 must be higher than the floating valve trays inside the tower body 100. Additionally, a reboiler is installed at the bottom of the tower body 100. The material at the bottom of the tower is heated by the reboiler, and the resulting high-temperature gas rises through the valve orifice 111 below the floating valve trays. New material (sodium bicarbonate solution) enters through the material inlet 102, is evenly distributed by the liquid distributor, and flows layer by layer through the floating valve trays inside the tower. Thus, the high-temperature gas inside the tower passes through the valve gaps and bubbles into the liquid layer, undergoing vigorous bubbling contact with the solution to complete the heat transfer and decomposition reaction.

[0024] As the solution flows layer by layer, it is continuously heated, causing sodium bicarbonate to fully decompose into sodium carbonate, releasing carbon dioxide and water vapor in the process. The gas is discharged at the end of gas outlet 101 by the action of fan 103. To utilize the heat of the gas, a heat exchanger 104 is installed at the exhaust end cover of fan 103. During the gas discharge process, heat is released through heat exchanger 104. Cold material is fed into heat exchanger 104 to exchange heat with the gas, and the preheated material is then discharged into the tower through material inlet 102.

[0025] refer to Figure 3The floating valve tray includes a floating valve plate body 110 and floating valves 112. The floating valve plate body 110 is fixed to a base 105 located on the inner ring of the tower body 100 by bolts and other components. The floating valves 112 are installed in multiple valve holes 111 opened on the surface of the floating valve plate body 110. The floating valves 112 are generally circular plate structures with multiple support arms circumferentially arranged on their outer edge. Each support arm fits against the inner wall of the valve hole 111, allowing the floating valves 112 to slide freely up and down within the valve hole 111. When the rising gas in the tower reaches a certain flow rate, the gas pushes the floating valves 112 upward. At this time, the support arms slide and guide along the inner wall of the valve hole 111, and the gas then passes through the gap between the valve hole 111 and the floating valve 112, passes through the floating valve plate body 110, and enters the upper liquid layer for bubbling contact. The key to maintaining the liquid layer thickness on the surface of the floating valve plate body 110 lies in the overflow weir 114 set on its liquid outlet side. The overflow weir 114 is fixed at a notch on one side of the float valve plate 110. After the material enters the top of the float valve plate 110, it flows laterally along the plate surface and is blocked by the overflow weir 114, thus forming and maintaining a liquid layer of a certain depth on the plate surface. Only when the depth of the liquid layer exceeds the top height of the overflow weir 114 will the material overflow over the overflow weir 114 to the notch, and then flow into the lower float valve plate 110 through the guide plate 115.

[0026] In addition, when the material flows into the lower floating valve plate 110, a baffle plate 113 is set to buffer the impact of the newly flowing material on the liquid layer on the plate surface. There are gaps between the two sides of the baffle plate 113 and the inner wall of the tower body 100, so that the newly flowing material can only slowly and evenly spread to the surface of the floating valve plate 110 through these gaps.

[0027] Due to pressure fluctuations within the tower body 100, the driving force on the float valve 112 is unstable, causing it to slide up and down frequently, posing a risk of jamming. To improve this situation, the present invention includes a sieve plate and a flow guiding mechanism 150. (Reference) Figure 5 The sieve plate is located below the float valve plate 110, and its top is provided with a partition 130. The partition 130 divides the space between the float valve plate 110 and the sieve plate into at least two independent airflow chambers, and the bottom of each airflow chamber is connected to the interior of the tower body 100. The flow guiding mechanism 150 is movably positioned at the connection between the airflow chamber and the tower body 100, and is used to control the alternating connection between multiple airflow chambers and the interior of the tower body 100 in a movable manner. In addition, a traction component is provided in the airflow chamber, which is flexibly connected to the float valve 112. When the airflow chamber is disconnected from the inside of the tower body 100, the traction component applies a downward pulling force to the float valve 112 to reset the stuck float valve 112.

[0028] Regarding the layout, refer to Figure 2The float valve plate 110 and the sieve plate are combined to form a tray unit. Multiple tray units are arranged sequentially from top to bottom within the tower body 100. Adjacent tray units are arranged in a staggered manner by rotating 180° horizontally, so that the liquid overflowing from the surface of the upper float valve plate 110 falls through the notch into the baffle plate 113 of the lower float valve plate 110, achieving orderly layer-by-layer flow of liquid.

[0029] refer to Figure 4 The diagram illustrates the specific structure of the sieve plate. The sieve plate includes a circular sieve mesh body 120, which, like the float valve plate 110, is fixed to a base 105 located on the inner wall of the tower body 100. A through-hole 122 is provided on one side of the sieve mesh body 120 corresponding to the notch in the float valve plate 110. This allows liquid overflowing from the top of the float valve plate 110 to flow downwards through the notch and directly fall into the lower float valve plate 110 via the through-hole 122, preventing liquid accumulation. During this process, a guide plate 115 located at the notch in the float valve plate 110 penetrates the through-hole 122, separating the through-hole 122 from the surface of the sieve mesh body 120, thus blocking and guiding the downward-flowing liquid and preventing it from entering the surface of the sieve mesh body 120.

[0030] Structurally, the screen plate 120 has multiple screen holes 121 on its surface. These screen holes 121 serve two purposes: firstly, they allow gas to pass through, maintaining a uniform distribution of airflow within the tower; secondly, when a small amount of material falls onto the surface of the screen plate 120 due to reasons such as jamming of the float valve 112, the material will be intercepted by the side plates 123 on the outer ring of the screen plate 120, while the area of ​​the screen holes 121 can still provide a place for heat transfer and decomposition reaction, ensuring that the remaining material is further processed.

[0031] In this invention, the arrangement of the partition 130 can be flexibly selected as needed. For example, the partition 130 can be designed as a straight line structure, dividing the space above the screen plate 120 into two independent airflow chambers; it can also be designed as a cross-shaped or star-shaped structure, correspondingly dividing the space into four or eight airflow chambers.

[0032] As a specific example, the present invention is described in detail with a straight partition 130. This straight partition 130 is vertically fixed to the middle of the upper surface of the screen plate 120, dividing the upper space into two airflow chambers, labeled as the first airflow chamber 131 and the second airflow chamber 132, respectively. The first airflow chamber 131 and the second airflow chamber 132 can alternately communicate with the interior of the tower body 100 under the action of the flow guiding mechanism 150.

[0033] Figure 7The specific structure of the flow guiding mechanism 150 is shown. This mechanism includes a baffle 151, the top surface of which is attached to the bottom surface of the screen plate 120, blocking the screen holes 121. The blocking area can be changed by rotating around an axis. In terms of blocking range, after a single rotation, the baffle 151 can completely cover all the screen holes 121 corresponding to the first airflow chamber 131 or the second airflow chamber 132. For example, when the baffle 151 rotates to a certain position, it can block all the screen holes 121 below the first airflow chamber 131, at which point the bottom of the first airflow chamber 131 is blocked from the interior of the tower body 100. Only when the baffle 151 continues to rotate and moves out of the area below the first airflow chamber 131 will the bottom of the first airflow chamber 131 reconnect with the interior of the tower body 100. Simultaneously, the baffle 151 then rotates into the area below the second airflow chamber 132, blocking its bottom screen holes 121, thus disconnecting the bottom of the second airflow chamber 132 from the interior of the tower body 100.

[0034] In the embodiment with two airflow chambers, the baffle 151 rotates 180 degrees each time, reciprocating around the center of the screen plate 120. Structurally, a bushing 152 is provided on one side of the baffle 151, which is rotatably fitted onto the outer ring of the bottom fixed shaft of the screen plate 120.

[0035] For the drive system, an external mounting method is adopted, with the motor 154 installed on the outer wall of the tower body 100. A transmission rod 153 is coaxially fixedly connected to the output end of the motor 154. This transmission rod 153 rotatably passes through the inner wall of the tower body 100 and is connected to the bushing 152 via a gear set. When the motor 154 rotates, it drives the bushing 152 to rotate via the transmission rod 153 and the gear set, thereby driving the baffle 151 to rotate.

[0036] In terms of drive control, the baffle 151 is driven to rotate intermittently, with the interval between two adjacent rotations being a preset switching cycle. This cycle can be reasonably set by those skilled in the art based on the actual operating conditions inside the tower (including but not limited to the frequency of float valve jamming, gas flow fluctuation amplitude, liquid leakage rate, etc.), for example, it can be set to several seconds to several minutes. Through this intermittent drive, the bottom of the first airflow chamber 131 and the second airflow chamber 132 alternately connect with the inside of the tower body 100 according to the preset cycle, realizing the periodic switching of airflow, thereby periodically forcibly resetting the float valves in each area.

[0037] like Figure 5 As shown, the traction component includes a traction arm 140 and a flexible connector disposed at the end of the traction arm 140. In this invention, the flexible connector is preferably a chain 141, which is made of metal material, with one end fixedly connected to the end of the traction arm 140 and the other end fixedly connected to the float valve 112. The structure of the traction arm 140 is described in detail below through specific embodiments.

[0038] exist Figure 5 and Figure 6 In the embodiment shown, one end of the traction arm 140 is located in the first airflow chamber 131, and the other end rotates through the partition 130 and extends into the second airflow chamber 132. Both ends of the traction arm 140 are connected to chains 141.

[0039] In practice, firstly, a corresponding number of traction arms 140 are set according to the number of float valves 112, and then each traction arm 140 is arranged at a different position on the partition 130 (the distribution can be referred to). Figure 6 To avoid mutual interference, insertion holes are made in the partition plate 130 corresponding to each traction arm 140. The shaft 142 is inserted into the insertion hole and rotates through the traction arm 140, thereby realizing the rotation of the traction arm 140.

[0040] The working principle of this embodiment can be found by referring to... Figure 5 When the flow guiding mechanism 150 blocks the bottom of the first airflow chamber 131, the rising gas inside the tower enters the second airflow chamber 132 through the sieve holes 121 (see the black dashed arrow) and continues to rise. During the ascent, it pushes the float valve 112 at the second airflow chamber 132 upward. When the float valve 112 moves upward, it drives the right end of the traction arm 140 to rotate upward via the chain 141. Correspondingly, the left end of the traction arm 140 rotates downward and pulls the float valve 112 at the first airflow chamber 131 downward via the chain 141, thereby causing the stuck float valve 112 to reset.

[0041] It should be noted that chain 141 can only transmit tension, not thrust. The normal opening of float valve 112 depends entirely on the pressure of the rising gas. Chain 141 is only used to apply a downward forced reset tension when the corresponding airflow chamber is cut off. When the float valve is stuck in the open position due to crystallization or high-temperature deformation, this tension is sufficient to make it fall back to the closed position; after the airflow chamber is reconnected, the rising gas can still push it up normally, thus ensuring the long-term reliable operation of the float valve.

[0042] exist Figure 8 and Figure 9 In the illustrated embodiment, the traction arms 140 are rotatably mounted on both sides of the partition 130. Unlike the previous embodiment, the traction arms 140 on both sides of the partition 130 are independently mounted and there is no connection between them, so that the float valve 112 can be reset by its own weight. In addition, a windward plate 143 is fixedly mounted on the side wall of the traction arm 140.

[0043] The working principle of this embodiment can be found by referring to... Figure 9When the baffle 151 blocks the bottom of the first airflow chamber 131, the rising gas inside the tower enters the second airflow chamber 132 through the sieve holes 121 (see the black dashed arrow) and continues to rise. During the ascent, the gas acts on the wind-facing plate 143, pushing the traction arm 140 located in the second airflow chamber 132 to rotate upward. At this time, the chain 141 on this side immediately becomes slack, and the float valve 112 in the second airflow chamber 132 can be normally pushed by the rising airflow. Since there is no airflow in the first airflow chamber 131, the traction arm 140 inside rotates downward under its own weight, thereby using its own weight to pull the float valve 112 in the first airflow chamber 131 downward via the chain 141, causing the stuck float valve 112 to reset.

[0044] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A pre-decarbonization device for a sodium bicarbonate solution evaporation system, comprising a tower body (100), a multi-layer floating valve tray disposed inside the tower body (100), and a gas outlet (101) and a material inlet (102) disposed at the top of the tower body (100), characterized in that, It also includes a sieve plate and a flow guiding mechanism (150); The sieve plate is located below the floating valve tower plate, and a partition plate (130) is provided on the top of the sieve plate. The partition (130) divides the space between the floating valve tray and the sieve plate into at least two independent airflow chambers, and the bottom of each airflow chamber is connected to the interior of the tower body (100); The flow guiding mechanism (150) is movably disposed at the connection between the airflow chamber and the tower body (100), and is used to control the alternating connection between multiple airflow chambers and the interior of the tower body (100) in a movable manner; The airflow chamber is equipped with a traction component that is flexibly connected to the float valve (112). When the airflow chamber is disconnected from the tower body (100), the traction component applies a downward pulling force to the float valve (112) to reset the stuck float valve (112).

2. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 1, characterized in that, The floating valve tower plate includes a floating valve plate body (110) and a floating valve (112) fixedly installed in the tower body (100). The float valve (112) is slidably installed in the valve hole (111) opened on the surface of the float valve plate (110); An overflow weir (114) for maintaining the liquid level is provided at the notch of the float valve plate (110).

3. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 2, characterized in that, The sieve plate includes a sieve plate (120) fixedly installed in the tower body (100). The sieve plate (120) has an opening (122) on one side corresponding to the notch of the float valve plate (110) so that the liquid overflowing from the top of the float valve plate (110) flows down into the lower float valve plate (110) through the notch. The surface of the screen plate (120) is provided with a plurality of screen holes (121).

4. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 3, characterized in that, When some liquid leaks abnormally through the valve hole (111), the surface of the screen plate (120) is used to temporarily receive the liquid that leaks abnormally from the valve hole (111), and thermally decompose the temporarily received liquid by means of airflow rising through the screen hole (121).

5. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 3, characterized in that, The partition (130) is a straight structure and is vertically fixed in the middle of the upper surface of the screen plate (120), dividing the space above the screen plate (120) into a first airflow chamber (131) and a second airflow chamber (132).

6. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 5, characterized in that, The flow guiding mechanism (150) includes a baffle (151) whose top surface is attached to the bottom surface of the screen plate body (120). A bushing (152) is provided on one side of the baffle (151). The bushing (152) is rotatably sleeved on the outer ring of the bottom fixed shaft of the screen plate body (120). It also includes a drive unit disposed on the outer wall of the tower body (100), the drive unit being connected to the bushing (152) for driving the baffle (151) to rotate.

7. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 6, characterized in that, The driving component drives the baffle (151) to rotate intermittently at a preset interval. Each time the rotation stops, the baffle (151) is located below the first airflow chamber (131) or the second airflow chamber (132).

8. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 5, characterized in that, The traction component includes a traction arm (140) and a flexible connector disposed at the end of the traction arm (140); The flexible connector is a chain (141) made of metal material. One end of the chain (141) is fixedly connected to the end of the traction arm (140), and the other end is fixedly connected to the float valve (112).

9. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 8, characterized in that, One end of the traction arm (140) is located in the first airflow chamber (131), and the other end rotates through the partition (130) and extends into the second airflow chamber (132). Both ends of the traction arm (140) are connected to chains (141) so that when the float valve (112) corresponding to one airflow chamber is pushed by gas, it drives the float valve (112) corresponding to the other airflow chamber to move down and reset.

10. The pre-decarbonization device for a sodium bicarbonate solution evaporation system according to claim 8, characterized in that, The traction arm (140) is rotatably mounted on both sides of the partition (130), and the side wall is fixedly provided with a wind-facing plate (143). When there is no airflow passing through the airflow chamber, the traction arm (140) drives the float valve (112) to reset by its own weight.

Images