A kind of slot width channel cooling plate feeding equipment

Abstract

The present application relates to the technical field of alumina production, and specifically discloses a type of wide channel cooling plate feeding equipment with a seed tank, which is characterized by comprising a seed tank, an incoming slag separator is arranged at the upper end of the seed tank, and a wide channel cooling plate heat exchanger is arranged at one end of the incoming slag separator, and the wide channel cooling plate heat exchanger is connected with the incoming slag separator and the seed tank; a feeding pump is arranged on one side of the seed tank, and the feeding pump is connected with the incoming slag separator through a connecting pipe; a discharge port is arranged in the middle of the seed tank, and the discharge port is connected with the feeding pump, and a discharge cock and a mother liquor flushing pipe are arranged between the feeding pump and the discharge port. The purpose of this patent is to solve the problem that the tank wall valve is not closed tightly after being damaged by abrasion, the aluminum hydroxide slurry generates siphoning, the incoming pipe cannot be disconnected, it is difficult to exit and repair, and there is a large safety risk.

Description

Technical Field

[0001] The invention relates to the technical field of alumina production, and in particular to a slot width channel cooling plate type feeding equipment. Background Art

[0002] In the alumina production process, seed decomposition is one of the important processes in alumina production, and seed decomposition is the key process for producing qualified aluminum hydroxide. In the industrial production of alumina, seed decomposition is generally carried out in a large seed tank, and natural cooling and forced cooling measures are taken to promote the decomposition of the mixed solution of sodium aluminate solution and aluminum hydroxide seeds (hereinafter referred to as aluminum hydroxide slurry), so as to obtain aluminum hydroxide products that meet the nucleation and particle size requirements. Forced cooling is generally carried out using a wide channel cooling plate heat exchanger, and the temperature of the aluminum hydroxide slurry is reduced in the heat exchange with the circulating coolant, thereby accelerating the seed decomposition process and improving the seed decomposition power. The seed tank is an important equipment in the alumina production process, and its function is to crystallize the aluminum oxide in the sodium aluminate solution in the form of aluminum hydroxide. In the seed tank, the performance of the feeding equipment directly affects the production efficiency and product quality.

[0003] Traditional seed tank feeding equipment usually uses tubular heat exchangers, but their heat exchange efficiency is low and it is difficult to meet the needs of large-scale production. In addition, tubular heat exchangers also have problems such as easy scaling and difficult cleaning, which seriously affect the service life and production efficiency of the equipment. In recent years, wide-channel plate heat exchangers have been used as heat exchange elements, which have the advantages of high heat exchange efficiency, low scaling, and easy cleaning. At the same time, the equipment also uses an advanced control system, which can achieve precise control of parameters such as feeding temperature and flow, thereby improving production efficiency and product quality.

[0004] At present, there are three feeding technology processes for traditional wide channel cooling plate heat exchangers. The first is to use a submerged feeding pump to lift and feed materials at the top of the seed tank. The submerged feeding pump is set to be submerged in the slurry for easy maintenance. Since the mixed liquid of sodium aluminate solution and aluminum hydroxide crystal seeds in the seed tank generates foam due to stirring, a certain amount of gas may be dissolved in the liquid. When the temperature, pressure or other conditions change, these dissolved gases may be released to form bubbles. At the same time, the feed may contain gas or entrained air. These gases may form bubbles after entering the seed tank, and during the operation of the seed tank, due to the buoyancy of the bubbles, they may rise to the surface of the liquid, or the air drawn in during the stirring process may form bubbles around the agitator. The submerged feeding pump may inhale the foam when sucking in the material; this may be because the material itself contains surfactants or other foam-generating substances, or it may be foam generated during the storage, transportation or processing of the material; it may also be that during the feeding process, the flow and pressure changes of the material may cause the formation of foam. For example, high-speed flowing materials may draw in air to form bubbles; or the materials may be subjected to shear force in the pipeline, which may also produce bubbles in various ways such as foam. An air chamber will appear in the pump cavity of the submerged feed pump, causing the feed pump to frequently "empty the pump", which in turn causes the feed flow rate of the wide channel cooling plate heat exchanger to fluctuate, thereby affecting the flow rate stability and heat exchange efficiency of the wide channel cooling plate heat exchanger, and also aggravating the blockage problem, frequent cleaning and maintenance, and increased production costs; the second is to discharge the material through the bottom of the sub-trough for circulation cooling, the published patent application CN201711392071.0, patent The patent is called a kind of divided slot tube bundle cooling system, which circulates and cools down through the bottom discharge of the divided slot. However, the discharge speed through the bottom is slow, which may affect the production efficiency, easily cause crystal breakage, and affect the particle size distribution of the product. The bottom discharge may cause sediment to accumulate at the bottom of the slot, and long-term operation may cause blockage, affecting the discharge efficiency and the normal operation of the slot. For some products that need to maintain the integrity of the crystal, the bottom discharge may cause the crystal to be subjected to a large impact force, resulting in crystal breakage, thereby affecting the product quality. The bottom discharge requires precise control of the discharge speed and time to avoid excessive or insufficient discharge.This has high technical requirements for the operator, is difficult to operate, and is inconvenient for subsequent maintenance and inspection; the third method is to set a slot wall valve on the slot wall at a certain height from the top of the seed tank to avoid the foam layer, because the foam layer will hinder the flow of the liquid, causing the liquid to be unevenly distributed in the slot, thereby affecting the reaction and the quality of the product. The bubbles in the foam layer may entrain gas, resulting in a shortened residence time of the gas in the slot, affecting the efficiency of the reaction, and the slot wall valve is set below the foam layer to ensure that the liquid can pass through the valve smoothly without being hindered by the foam layer. Avoiding the foam layer can reduce the risk of gas being entrained and improve the utilization efficiency of the gas. In addition, the intermediate discharge can prevent the crystal from being subjected to a large impact force at the bottom, thereby reducing the breakage of the crystal. This is very important for products that need to maintain the integrity of the crystals, and can improve the quality and yield of the products. Through intermediate discharge, the crystallization process can be better controlled, and the discharge speed and flow rate can be adjusted as needed to control the growth rate and particle size distribution of the crystals. After the aluminum hydroxide slurry is discharged from the tank wall valve of the seed tank, it is transported to the wide channel cooling plate heat exchanger through the feed pump set under the seed tank to achieve the purpose of heat exchange. This method successfully solves the impact of foam generated by organic impurities on the heat exchange system, but as the tank wall valve is continuously flushed by aluminum hydroxide slurry particles, the tank wall valve is damaged by abrasion and cannot be closed tightly, and the aluminum hydroxide slurry produces siphoning, resulting in the inability to cut off the material in the feeding process. There is a great safety risk. The material needs to be completely interrupted. The material level of the seed tank needs to be lowered to below the tank wall valve before maintenance can be achieved. In addition, the construction is difficult, the risk factor of high-altitude operations is high, and the cost of spare parts is high. Summary of the invention

[0005] In view of the shortcomings of the prior art, the technical problem solved by the invention is to provide a kind of slot wide channel cooling plate feeding equipment, which has the purpose of improving the efficiency of the heat exchange cycle of crystal precipitation in the slot and reducing the cost.

[0006] In order to solve the above problems, the technical solution adopted by the invention is: a seed tank wide channel cooling plate feeding equipment, characterized in that: it includes a seed tank, an incoming material slag separator is arranged at the upper end of the seed tank, and a wide channel cooling plate heat exchanger is arranged at one end of the incoming material slag separator, and the wide channel cooling plate heat exchanger is connected with the incoming material slag separator and the seed tank; a feeding pump is arranged on one side of the seed tank, and the feeding pump is connected with the incoming material slag separator through a connecting pipe; a discharge port is arranged in the middle of the seed tank, and the discharge port is connected with the feeding pump, and a discharge cock and a mother liquor flushing pipe are arranged between the feeding pump and the discharge port.

[0007] The beneficial effects of this solution are as follows: in the traditional solution, a tank wall valve is set on the tank wall at a certain height from the top of the seed tank, and the installation is avoided in the foam layer position, and the influence of foam generated by impurities such as organic matter on the heat exchange system is successfully solved. However, as the tank wall valve is continuously flushed by the aluminum hydroxide slurry particles, the tank wall valve is damaged by abrasion and cannot be closed tightly, and the aluminum hydroxide slurry generates siphoning, resulting in the inability to interrupt the feeding process. In this solution, a discharge port is set in the middle of the seed tank, and the discharge port is connected to the feeding pump to avoid the tank wall valve being damaged by abrasion and cannot be closed tightly, and the aluminum hydroxide slurry generates siphoning, resulting in the inability to interrupt the feeding process, which poses a great safety risk, and completely interrupts the material to avoid the tank wall valve being flushed and cannot be closed tightly. In this solution, the tank wall valve set on the tank wall of the seed tank is no longer used, purchased, or maintained, thereby reducing the energy system and labor maintenance costs of the valve such as electricity and gas, the labor cost of valve inspection and repair, and the purchase cost of spare parts.

[0008] Furthermore, the discharge port is set as an inclined structure with an inclination angle of 45° and is oriented toward the long axis of the stirring device. The 45° angle design can make the material in the U-shaped tube produce a certain swirl during the flow process, thereby increasing the degree of mixing between the materials. At the same time, the direction of the long axis of the stirring device can make the material better contact with the action area of ​​the stirring device, further improving the mixing effect. By setting the angle of the U-shaped tube to 45°, the deposition of the material in the tube can be reduced. The material is affected by gravity and inertia during the flow process. The 45° angle can make the material flow more easily and reduce the possibility of deposition.

[0009] Furthermore, a U-shaped tube is provided between the discharge port and the feed pump. The U-shaped tube is provided on the seed tank. One end of the U-shaped tube is connected to the discharge port and the other end is connected to the feed pump. The U-shaped tube can form a liquid seal to prevent the material from flowing back to the seed tank when the pump stops working. The U-shaped tube can play a buffering role and reduce the pressure fluctuation of the material during the transportation process. This helps to protect the feed pump and other equipment from the influence of excessively high or low pressure and prolong the service life of the equipment. The setting of the U-shaped tube can increase the flexibility of the system and make the connection between the discharge port and the feed pump more convenient.

[0010] The U-shaped tube is provided with an exhaust valve, which is connected to the U-shaped tube. The exhaust valve can remove the gas in the U-shaped tube to prevent the accumulation of bubbles. This is very important to ensure the smooth and stable flow of liquid, avoiding the influence of bubbles on the flow and pressure. Gas may be trapped in the U-shaped tube, forming an air lock, which hinders the flow of liquid. The existence of the exhaust valve can remove these gases in time, prevent the occurrence of air lock, and ensure the normal operation of the system; at the same time, the exhaust valve can be set to cut off the siphon of the U-shaped tube more quickly.

[0011] The drain valve is arranged at the groove surface of the U-shaped tube. The drain valve is arranged at the groove surface of the U-shaped tube, so that the operator can conveniently perform the draining operation. When the liquid in the U-shaped tube needs to be drained, the drain valve only needs to be opened, and the liquid can flow out smoothly without disassembling or moving other parts. By arranging the drain valve at the groove surface of the U-shaped tube, the residual liquid in the U-shaped tube can be minimized. When the drain valve is opened, the liquid can be completely discharged, avoiding the accumulation and residue of the liquid in the U-shaped tube, thereby reducing the impact on subsequent operations.

[0012] Furthermore, a Y-type slurry valve is provided on the incoming pipe at one end of the incoming slag separator, and the Y-type slurry valve is arranged at the outlet of the feed pump. The Y-type slurry valve can adjust the flow rate of the slurry. By controlling the opening and closing of the valve, the supply amount of the slurry can be accurately controlled, thereby ensuring the stability and consistency of the production process; the design of the Y-type slurry valve can effectively prevent the slurry from flowing back. When the feed pump stops working or fails, the valve can be automatically closed to prevent the slurry from flowing back to the pump body or other equipment, thereby protecting the safety of the equipment and process; setting the Y-type slurry valve at the outlet of the feed pump can reduce the impact and wear on the pump when it is closed, and the slow closing function of the valve can reduce the water hammer effect and extend the service life of the pump.

[0013] Furthermore, the feed pump is arranged at the zero plane under the tank of the seed tank. The feed pump located at the zero plane under the tank can better utilize the gravity effect, so that the material flows into the pump more easily, reducing the resistance of the feed and improving the feed efficiency. The feed pump is arranged at the zero plane under the tank to reduce the suction height of the pump, reduce the risk of cavitation, and extend the service life of the pump.

[0014] Furthermore, the mother liquor flushing pipe is provided with a slurry control valve, which is arranged in a Y-shaped structure. The design of the Y-type control valve can reduce the accumulation of solid particles in the valve and reduce the risk of blockage, which is particularly important for the slurry flushing system containing solid particles, and can ensure the normal operation and flushing effect of the valve.

[0015] Furthermore, the discharge cock and the mother liquor flushing pipe are arranged in sequence from near to far near the feed pump. The mother liquor flushing pipe is arranged close to the discharge cock, so that the pipeline can be flushed in time after discharging, avoiding material residue and blockage, and ensuring smooth discharging next time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the present invention. DETAILED DESCRIPTION

[0017] The following is further described in detail through specific implementation methods:

[0018] The figure marks in the drawings of the specification include: seed tank 1, stirring device 2, wide channel cooling plate heat exchanger 3, incoming slag separator 4, incoming pipe 5, Y-type slurry valve 6, feed pump 7, discharge cock 8, slurry control valve 10, mother liquor flushing pipe 11, U-shaped pipe 12, drain valve 13, discharge port 14, feed pipe 15.

[0019] Embodiment 1 is basically as attached Figure 1 As shown: a seed separation tank wide channel cooling plate feeding equipment, including a seed separation tank 1, a stirring device 2 is arranged at the upper end of the seed separation tank 1, and the stirring device 2 is inserted into the bottom position of the seed separation tank 1. The stirring device 2 can promote the uniform mixing of materials in the seed separation tank 1. Through stirring, materials of different components can be fully contacted and fused to ensure that the properties of materials in various parts of the tank are uniform; an incoming material slag separator 4 is arranged at the upper end of the seed separation tank 1. The accumulation of impurities may interfere with the stability of the seed separation process, resulting in changes in the reaction rate, crystal form, etc. The incoming material slag separator 4 can keep the material clean, ensure the stable operation of the process, and improve In order to improve production efficiency and product consistency, a wide channel cooling plate heat exchanger 3 is arranged on one side of the incoming slag separator 4. One end of the wide channel cooling plate heat exchanger 3 is connected with the incoming slag separator 4, and the other end is connected with the seed separation tank 1. A feed pump 7 is arranged on one side of the seed separation tank 1. One end of the feed pump 7 is connected with the incoming slag separator 4 through an incoming pipe 5. A Y-type slurry valve 6 is arranged on the incoming pipe 5 at one end of the incoming slag separator 4. The Y-type slurry valve 6 is arranged at the outlet of the feed pump 7. The Y-type slurry valve 6 can adjust the flow rate of the slurry. By controlling the opening and closing of the valve, the supply amount of the slurry can be accurately controlled, thereby ensuring the stability and consistency of the production process.

[0020] The feed pump 7 is arranged at the zero plane under the seed tank 1. The zero plane under the tank refers to a plane below a certain tank body or container that is at the same horizontal height as the ground or reference plane. The feed pump 7 located at the zero plane under the tank can better utilize the effect of gravity, so that the material can flow into the pump more easily, reducing the resistance of feeding and improving the feeding efficiency. A feed pipe 15 is arranged at the end of the feed pump 7 away from the incoming pipe 5. The feed pipe 15 is connected to the U-shaped pipe 12 arranged on the seed tank 1, and a discharge cock 8 and a mother liquor flushing pipe 11 are arranged on the feed pipe 15. A slurry control valve 10 is arranged on the mother liquor flushing pipe 11. The slurry control valve 10 is arranged in a Y-shaped structure, and the flow channel shape of the slurry control valve 10 is Y-shaped. This design enables the slurry to produce diversion and swirl effects when passing through the valve. Diversion can reduce the concentration of particles in the valve, while swirl helps to disperse the particles and prevent them from depositing. Due to the special flow channel shape and large flow area of ​​the Y-type control valve, the slurry can produce a certain flushing effect when passing through the valve. This flushing effect helps to clear the particles that may accumulate in the valve, has a certain self-cleaning effect, reduces the risk of blockage, and can ensure the normal operation and flushing effect of the valve. The discharge cock 8 and the mother liquor flushing pipe 11 are arranged in sequence from near to far close to the feed pump. The mother liquor flushing pipe 11 is arranged close to the discharge cock 8, which can flush the feed pipe in time after discharging, avoid material residue and blockage, and ensure smooth discharging next time.

[0021] One end of the U-shaped tube 12 is connected to the feed pipe 15, and the other end is inserted into the seed tank 1, and an emptying valve 13 is arranged at the groove surface position of the U-shaped tube 12. The groove surface position of the U-shaped tube usually refers to the surface position of the curved part of the U-shaped tube. In the U-shaped tube, the groove surface refers to the inner curved surface of the U-shaped tube, that is, the part forming the U shape, so that the operator can conveniently perform the emptying operation. The U-shaped tube 12 is located on the U-shaped tube 12. A discharge port 14 is arranged at one end of the U-shaped tube 12 close to the seed tank 1. The discharge port 14 is arranged in the middle of the seed tank 1, and is arranged at a specific angle to the U-shaped tube 12. The inclination angle of the discharge port 14 is 45°. Inclining the discharge port 14 by 45° can reduce the pressure drop, reduce energy consumption, and improve the energy efficiency of the system. In the process of crystallization, the inclined discharge port 14 can change the flow direction and velocity distribution of the fluid in the U-shaped tube 12. This change helps reduce the turbulence and eddy currents of the fluid, allowing the fluid to flow more smoothly. Smooth fluid flow can provide a more uniform distribution of solutes, thereby promoting uniform growth of crystals. When the fluid passes through a vertical discharge port, the crystals may be subjected to a greater impact force, resulting in collisions and agglomeration between crystals. The inclined discharge port can reduce this impact force and reduce collisions and agglomerations of crystals. This helps maintain the independence and integrity of the crystals and reduce the formation of defects; the inclined discharge port can reduce the deposition and blockage of crystals in the U-tube. Crystals slide more easily on the inclined surface, avoiding the accumulation of crystals at the discharge port. This helps to keep the U-shaped tube 12 unobstructed; at the same time, the 45° inclination angle allows the fluid to flow more smoothly at the discharge port 14, reducing the generation of turbulence and eddies, which helps to improve the stability and uniformity of the fluid and reduce the impact on pipelines and equipment. The inclined discharge port 14 causes the fluid to undergo a change of direction during the flow. When the fluid passes through the discharge port, the bubbles are affected by the centrifugal force and are pushed to the outside of the discharge port 14. This centrifugal force helps to separate the bubbles from the fluid and prompts them to move toward the outlet of the discharge port. The inclined discharge port 14 provides a rising channel for the bubbles. Since the density of the bubbles is relatively low, they tend to float upward. The inclination of the discharge port allows the bubbles to rise along the slope of the discharge port and eventually be discharged from the fluid. A vertical discharge port may cause bubbles to be retained in the discharge port, forming an area where bubbles accumulate. The inclined discharge port reduces this retention phenomenon, making it easier for bubbles to be carried away and discharged by the fluid, avoiding the accumulation of bubbles in the pipeline to form air blockage, thereby ensuring continuous extraction of the fluid. Reducing pressure drop and fluid fluctuation can reduce the stress and fatigue of the pipeline system, extend the service life of the pipeline and equipment, and improve the reliability of the system.

[0022] The specific working process of the seed tank 1 is as follows: when in use, the seed tank 1 is used to contain alumina slurry, and when in use, the stirring device 2 works to stir the aluminum hydroxide slurry. When in use, the drain valve 13 is closed, and after the aluminum hydroxide slurry fills the U-shaped tube 12, the feed pump 7 is started, and the outlet Y-shaped slurry valve 6 of the feed pump 7 is opened, and the aluminum hydroxide slurry is siphoned to the feed pump 7, and then transported to the wide channel cooling plate heat exchanger 3 to achieve continuous operation, thereby improving the stable transportation effect of the feed flow of the wide channel cooling plate heat exchanger 3 and ensuring the forced cooling and heat exchange efficiency of the wide channel cooling plate heat exchanger 3;

[0023] When it is necessary to stop, the drain valve 13 is opened, the feed pipe 15 on the feed pump 7 sucks in the atmosphere, the siphon is broken, the self-pressure state of the aluminum hydroxide slurry is automatically interrupted, and the feed pump 7 exits safely after discharging the material through the discharge cock 8. The safety factor is greatly improved, ensuring the safety of the inspection and maintenance process.

[0024] The above is only an embodiment of the invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the invention, which should also be regarded as the scope of protection of the invention, and these will not affect the effect of the implementation of the invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A slot width channel cooling plate feeding equipment, characterized in that: It comprises a seed tank, at the upper end of which is provided an incoming material separator, one end of which is provided with a wide channel cooling plate heat exchanger, which is connected with the incoming material separator and the seed tank; one side of the seed tank is provided with a feed pump, which is connected with the incoming material separator through a connecting pipe; a discharge port is provided in the middle of the seed tank, which is connected with the feed pump, and a discharge cock and a mother liquor flushing pipe are provided between the feed pump and the discharge port; the discharge port is an inclined structure with an inclination angle of 45° and faces the middle of the stirring device. Long axis direction; a U-shaped tube is arranged between the discharge port and the feed pump, and the U-shaped tube is arranged on the seed tank, one end of the U-shaped tube is connected with the discharge port, and the other end is connected with the feed pump; a drain valve is arranged on the U-shaped tube, and the drain valve is connected with the U-shaped tube; the drain valve is arranged at the groove surface of the U-shaped tube; a Y-shaped slurry valve is arranged on the incoming pipe at one end of the incoming slag separator, and the Y-shaped slurry valve is arranged at the outlet of the feed pump; the feed pump is arranged at the zero plane under the tank of the seed tank; the mother liquor flushing pipe is provided with a slurry control valve, and the slurry control valve is arranged in a Y-shaped structure.

2. The slot width channel cooling plate type feeding equipment according to claim 1 is characterized in that: The discharge cock and the mother liquid flushing pipe are arranged in sequence from near to far near the feed pump.

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