A waste heat boiler blowdown water recovery device and method

Abstract

The present application belongs to sewage treatment technical field, disclose a kind of waste heat boiler blowdown water recovery device and method, the device includes by pipeline intercommunication boiler, slurry pump, agitator tank and gas storage tank;Agitator tank includes being located in the agitator tank stirring assembly and for driving stirring assembly motor;Stirring assembly includes first drive rod, first drive rod is hollow structure, first drive rod is connected with the output end of motor, first drive rod is communicated with gas storage tank by swivel joint;Second drive rod, second drive rod is hollow structure, second drive rod is communicated with first drive rod;First stirring rod, stirring rod is hollow structure, the number of first stirring rod is two groups, and respectively with first drive rod and second drive rod communication;Second stirring rod, second stirring rod is hollow structure, second stirring rod is located in first stirring rod, and with first stirring rod communication, second stirring rod is equipped with several spray holes;The present application solves the problem that carbon dioxide and ash water reaction is not sufficient.

Description

TECHNICAL FIELD

[0001] The present scheme belongs to the technical field of sewage treatment, and particularly relates to a waste heat boiler blowdown water recycling device and method. BACKGROUND

[0002] Boiler ash water, which is a mixture of unburned ash and cooling water in the operation of coal-fired or oil-fired boilers, contains high concentrations of suspended solid waste and harmful substances, and belongs to the category of industrial wastewater. Recycling and processing ash water can purify these harmful substances and meet environmental emission standards.

[0003] The ash water treatment process includes adjusting the pH to optimize the addition of flocculants, promoting the precipitation of suspended solids, accelerating the removal of calcium carbonate, magnesium and other hardness by introducing carbon dioxide, and strengthening the precipitation of flocculants, integrating large particles, accelerating sedimentation, and improving filtration and clarification to ensure that the water quality after treatment meets the emission standards.

[0004] Referring to the existing document (announcement) No. CN117401797A, a boiler ash water treatment and recycling device is disclosed, which comprises a combined power shaft, a spiral blade, an aeration assembly and a buffer assembly. The device realizes the downward swirling of the ash water in the sedimentation tank body and the upward surging of the reaction gas, and the reaction between the ash water and the gas is enhanced by the collision of the two.

[0005] The swirling ash water and the upward surging gas react, which aims to enhance the mixing of the two by swirling and gas surging. However, the high-speed rotating flow caused by swirling leads to uneven distribution of carbon dioxide in the ash water, often forming large bubbles instead of small bubble groups, thereby reducing the contact area between carbon dioxide and ash water, and not making the reaction between the two more sufficient. Moreover, since the reaction between carbon dioxide and ash water mainly depends on the size of the bubbles and the residence time of the gas in the ash water, large bubbles quickly rise and escape the water surface, reducing the reaction time with the ash water. In addition, swirling can disturb the sediments in the sedimentation tank, causing resuspension of the sediments. Therefore, the swirling method is not ideal for mixing carbon dioxide and gas. SUMMARY

[0006] The purpose of the present scheme is to provide a waste heat boiler blowdown water recycling device to solve the problem of insufficient reaction between carbon dioxide and ash water.

[0007] In order to achieve the above purpose, the present scheme provides a waste heat boiler blowdown water recycling device, which comprises a boiler, a slurry pump, a stirring tank and a gas storage tank connected by pipelines from left to right, and carbon dioxide is arranged in the gas storage tank; the stirring tank comprises a stirring assembly arranged in the stirring tank and a motor for driving the stirring assembly; the stirring assembly comprises:

[0008] A first driving rod, which is hollow, is connected with the output end of the motor and communicates with the gas storage tank through a rotary joint;

[0009] A second driving rod, which is hollow, communicates with the first driving rod;

[0010] A first stirring rod, which is hollow, is in two groups and communicates with the first driving rod and the second driving rod respectively;

[0011] A second stirring rod, which is hollow, is slidably arranged in the first stirring rod and communicates with the first stirring rod, and is provided with a plurality of spray holes.

[0012] The principle of the present scheme is that the ash water is introduced into the stirring tank by the slurry pump, the high-pressure carbon dioxide is introduced into the first driving rod through the rotary joint of the gas storage tank, and then introduced into the second driving rod, the first stirring rod and the second stirring rod in turn, and finally sprayed into the ash water from the spray holes. At the same time, the motor drives the driving rod and the stirring rod to rotate, thereby disturbing the ash water.

[0013] The effect of the present scheme is that: (1) when the motor drives the stirring assembly to rotate, the centrifugal force generated promotes the diffusion of carbon dioxide bubbles sprayed from the spray holes to the periphery of the stirring tank, thereby increasing the surface area of carbon dioxide in contact with the ash water, accelerating the gas dissolution process and reaction rate. At the same time, the stirring assembly disturbs the turbulent flow of the ash water, accelerating the mixing of the ash water and the carbon dioxide. Furthermore, the centrifugal force generated by high-speed rotation can make larger bubbles break into smaller bubbles. Small bubbles have a larger surface area and can more effectively contact the solute in the ash water than large bubbles, thereby promoting the reaction between carbon dioxide and the ash water. (2) In the present scheme, in order to better achieve the dispersion effect of carbon dioxide in the ash water, the motor speed can be controlled. When the motor speed is slow, the carbon dioxide bubbles will gather in the middle area of the stirring tank due to the smaller centrifugal force; when the motor speed is fast, the bubbles will be dispersed to the periphery of the stirring tank due to the larger centrifugal force. Therefore, the motor speed can be periodically changed to adjust the distribution pattern of the bubbles in the stirring tank, so that they rise in a "layered" manner, which not only promotes the uniform distribution of bubbles in the ash water, but also increases the contact time of the gas and the ash water due to the layering of the bubbles during the rising process. At the same time, it can further promote the mixing of the ash water and the carbon dioxide and accelerate the dissolution of the gas.

[0014] Further, the top of the stirring tank is provided with a sealing cover.

[0015] The principle and effect of the scheme are that: the solubility of carbon dioxide in grey water is relatively low, but the solubility will increase under high pressure environment. The high pressure carbon dioxide is introduced into the stirring tank through the gas storage tank, and the sealing cover is arranged to ensure the sealing of the stirring tank and increase the solubility of carbon dioxide in grey water.

[0016] Further, the second driving rod is slidingly arranged in the first driving rod, and the second driving rod is connected with a spring for resetting.

[0017] The principle and effect of the scheme are that: (1) when the first driving rod is introduced into carbon dioxide, the second driving rod is pushed out of the first driving rod, so that the second stirring rod connected with the second driving rod is away from the first stirring rod; after stopping the introduction of carbon dioxide, the second driving rod is retracted into the first stirring rod under the driving of the spring. (2) In the process of reaction of carbon dioxide and grey water, the grey water needs to be stirred. The second stirring rod is separated from the first stirring rod, the distance between them is increased, the stirring range is expanded, and the stirring area is increased. After stopping the introduction of carbon dioxide, the flocculating agent needs to be added in the stirring tank to gather into larger flocs, so that the grey water is precipitated. At this time, if the second stirring rod continuously stirs at the bottom of the stirring tank, the structure of the flocs will be damaged by the flocculating agent, so that the flocs are difficult to settle. However, the stirring cannot be stopped at this time. In the initial stage of adding the flocculating agent, if the stirring is stopped, it is not conducive to the uniform mixing of the flocculating agent and the suspended particles in the grey water, resulting in uneven flocculation effect. Therefore, by retracting the second driving rod and the second stirring rod, the grey water can be stirred, and the flocs can also be prevented from being damaged.

[0018] Further, the stirring tank is provided with a supporting seat matched with the second driving rod.

[0019] The principle and effect of the scheme are that: when the second driving rod is extended to the maximum stroke, the end of the second driving rod will be in contact with the supporting seat and rotationally connected with the supporting seat, and the supporting seat provides auxiliary support for the second driving rod.

[0020] Further, the number of the first stirring rods is multiple, and the multiple first stirring rods are arranged along the axis of the first driving rod in a circumferential direction.

[0021] The principle and effect of the scheme are that: the coverage during stirring is increased, and the stirring is more uniform.

[0022] Further, the second stirring rod is connected with a hollow guide rod, the outer wall of the guide rod is provided with a threaded guide groove, the second stirring rod is provided with a bolt matched with the guide groove, the guide rod is connected with an elastic rope, and the free end of the elastic rope is connected with the first stirring rod.

[0023] The principle and effect of the scheme are that: (1) when the first stirring rod is connected with carbon dioxide and the centrifugal force generated by the rotation of the motor, the guide rod is pushed, and under the cooperation of the bolt, the guide rod drives the second stirring rod to move along the threaded track of the guide groove, so that the second stirring rod rotates and extends out of the first stirring rod, and the spray hole faces upward. After stopping the carbon dioxide from being connected, the guide rod is rotated by 90 degrees under the driving of the elastic rope, so that the spray hole faces downward; after the motor stops, the guide rod drives the second stirring rod to retract into the first stirring rod under the driving of the elastic rope. (2) When the carbon dioxide is connected, the second stirring rod is extended and the spray hole faces upward, not only to increase the stirring area, but also because the second driving rod and the first driving rod are telescopic structures. When the spray hole sprays gas, there is a downward pressure on the second stirring rod and the second driving rod, so that the second driving rod is more stable in contact with the supporting seat. (3) After stopping the carbon dioxide from being connected, the flocculating agent needs to be added to the water. In order to avoid the flocculation from settling in the spray hole and causing the spray hole to be blocked, the spray hole is rotated downward. At this time, the gray water still needs to be stirred, so the second stirring rod cannot be retracted into the first stirring rod to avoid reducing the stirring area. (4) When the addition of the flocculating agent is stopped and the gray water is static, the motor stops rotating, and the second stirring rod needs to be retracted into the first stirring rod to avoid the flocculation from blocking the spray hole when the flocculation is cleaned.

[0024] A waste heat boiler blowdown water recycling method, comprising the application of a waste heat boiler blowdown water recycling device as described, comprising the following steps:

[0025] Step S10: gray water introduction, starting the slurry pump to introduce the gray water into the stirring tank, preparing for the next step of stirring and reaction;

[0026] Step S20: carbon dioxide connection, opening the connection valve between the gas storage tank and the stirring tank, and connecting the high-pressure carbon dioxide in the gas storage tank to the first driving rod of the stirring tank through the rotary joint, then through the second driving rod, the first stirring rod and the second stirring rod in turn, and finally sprayed from the spray hole on the second stirring rod into the gray water;

[0027] Step S30: stirring and reaction, starting the motor to drive the stirring assembly to rotate and generate centrifugal force, promoting the diffusion of carbon dioxide bubbles to the four corners of the stirring tank, increasing the contact area with the gray water, and accelerating the gas dissolution process and reaction rate;

[0028] Step S40: adjusting the bubbles, by periodically changing the speed of the motor, adjusting the distribution form of the bubbles in the gray water, realizing layered rising, prolonging the contact time of the gas with the gray water, and accelerating the dissolution and reaction;

[0029] Step S50: adding reagent, after 1h of reaction of carbon dioxide and gray water, adding a flocculating agent;

[0030] Step S60: Adjust the stirring range, accelerate the stirring speed at the initial stage of flocculant addition to promote the mixing of flocculant and ash water, and when the flocculation is observed at the bottom of the reaction tank, reduce the stirring intensity and retract the second driving rod and the stirring rod to avoid destroying the flocculation and promote the settlement of the flocculation;

[0031] Step S70: After the flocculation is settled, the sediment is discharged through the discharge port at the bottom of the stirring tank, and the treated ash water is treated by filtration or further purification steps, and then recycled or discharged after reaching the discharge standard. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 Structure diagram of the waste heat boiler blowdown water recovery device of the present application Figure 1 ;

[0033] Figure 2 Structure diagram of the waste heat boiler blowdown water recovery device of the present application Figure 2 ;

[0034] Figure 3 Structure diagram of the stirring tank of the present application

[0035] Figure 4 Structure diagram of the stirring assembly of the present application Figure 1 ;

[0036] Figure 2 Structure diagram of the stirring assembly of the present application Figure 6 ;

[0037] Figure 7 Structure diagram of the first driving rod and the second driving rod of the present application

[0038] Figure 8 Structure diagram of the guide rod and the second stirring rod of the present application

[0039] Figure 1 Cross-sectional view of the guide rod and the second stirring rod of the present application

[0040] The reference signs in the drawings of the specification include: boiler 1, slurry pump 2, stirring tank 3, stirring assembly 31, motor 32, first driving rod 311, second driving rod 312, spring 313, first stirring rod 314, second stirring rod 315, injection hole 3151, guide rod 316, guide groove 3161, bolt 317, elastic rope 318, sealing cover 33, support seat 34, gas storage tank 4. DETAILED DESCRIPTION

[0041] The concept and the generated technical effects of the present application will be described clearly and completely in combination with the embodiments below, so as to fully understand the purposes, features and effects of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, but not all the embodiments, and other embodiments obtained by those skilled in the art without creative labor based on the embodiments of the present application all belong to the protection scope of the present application:

[0042] Please refer to Figure 2 and Figures 3-5 A waste heat boiler blowdown water recycling device, comprising a boiler 1, a slurry pump 2, a stirring tank 3 and a gas storage tank 4 connected by pipelines from left to right in sequence, and the gas storage tank 4 is provided with carbon dioxide.

[0043] Please refer to Figure 6 The top of the stirring tank 3 is provided with a sealing cover 33 to ensure the sealing of the stirring tank and increase the solubility of carbon dioxide in the ash water. The stirring tank 3 comprises a stirring assembly 31 arranged in the stirring tank 3 and a motor 32 for driving the stirring assembly 31, the motor 32 is a PID servo motor and is electrically connected with a PID controller, the stirring assembly 31 comprises a first driving rod 311 and a second driving rod 312, both of which are hollow structures, the first driving rod 311 is connected with the output end of the motor 32 and communicates with the gas storage tank 4 through a rotary joint; the second driving rod 312 communicates with the first driving rod 311, and the bottom of the stirring tank 3 is provided with a supporting seat 34 matched with the second driving rod 312, when the second driving rod 312 extends to the maximum stroke, the end of the second driving rod 312 will contact with the supporting seat 34 and is rotatably connected therewith, and the supporting seat 34 provides auxiliary support for the second driving rod 312. The first driving rod 311 and the second driving rod 312 are both provided with a first stirring rod 314, the first stirring rod 314 is a hollow structure and two groups of first stirring rods 314 respectively communicate with the first driving rod 311 and the second driving rod 312, the number of the first stirring rods 314 is four first stirring rods 314 arranged circumferentially along the axis of the first driving rod 311 to increase the coverage during stirring and make the stirring more uniform; a second stirring rod 315 is slidably arranged in the first stirring rod 314, the second stirring rod 315 is a hollow structure, and a plurality of spray holes 3151 are formed in the free end of the second stirring rod 315.

[0044] The specific working principle is as follows: water is introduced into the stirring tank 3 by the slurry pump 2, the gas storage tank 4 introduces high-pressure carbon dioxide into the first driving rod 311 through the rotary joint, and then the second driving rod 312, the first stirring rod 314 and the second stirring rod 315 are sequentially introduced, and finally sprayed from the spray hole 3151 into the ash water. At the same time, the motor 32 drives the first driving rod 311 and the second driving rod 312 and the first stirring rod 314 and the second stirring rod 315 to rotate, thereby disturbing the ash water. When the motor 32 drives the stirring assembly 31 to rotate, the centrifugal force generated promotes the diffusion of carbon dioxide bubbles sprayed from the spray hole 3151 to the periphery of the stirring tank 3, thereby increasing the surface area of the carbon dioxide in contact with the ash water, accelerating the gas dissolution process and reaction rate. At the same time, the stirring assembly 31 disturbs the turbulent flow of the ash water, accelerating the mixing of the ash water and the carbon dioxide. Furthermore, the centrifugal force generated by high-speed rotation can break larger bubbles into smaller bubbles. Small bubbles have a larger surface area and can more effectively contact the solute in the ash water than large bubbles, promoting the reaction between carbon dioxide and ash water.

[0045] To better achieve the dispersion effect of carbon dioxide in the ash water, the speed of the motor 32 can be controlled. When the motor 32 rotates at a slow speed, the carbon dioxide bubbles are subjected to a small centrifugal force and will gather in the middle area of the stirring tank 3; when the motor 32 rotates at a high speed, the bubbles are subjected to a large centrifugal force and will be dispersed to the periphery of the stirring tank. Therefore, the speed of the motor 32 can be periodically changed to adjust the distribution pattern of the bubbles in the stirring tank, so that they rise in a "layered" manner. This not only promotes the uniform distribution of bubbles in the ash water, but also increases the contact time between the gas and the ash water due to the layering of the bubbles during the rising process. At the same time, it can further promote the mixing of the ash water and the carbon dioxide and accelerate the dissolution of the gas.

[0046] Please refer to Figure 7 , the second driving rod 312 is slidingly arranged in the first driving rod 311, and the second driving rod 312 is connected with a spring 313 for resetting the second driving rod 312, and the two ends of the spring 313 are fixedly connected with the first driving rod 311 and the second driving rod 312, respectively.

[0047] The specific working principle is as follows: in the process of reaction of carbon dioxide and grey water, the grey water needs to be stirred. When the first driving rod 311 is connected with carbon dioxide, the second driving rod 312 is pushed out of the first driving rod 311, so that the second stirring rod 315 connected with the second driving rod 312 is away from the first stirring rod 314, the second stirring rod 315 is separated from the first stirring rod 314, the distance between them is increased, the stirring range is expanded, and the stirring area is increased. After stopping the introduction of carbon dioxide, the flocculating agent needs to be added in the stirring tank 3 to gather into larger flocs, so as to precipitate the grey water. At this time, if the second stirring rod 315 continuously stirs at the bottom of the stirring tank 3, the structure of the flocs will be damaged by the flocculating agent, so that the flocs are difficult to settle. However, stirring cannot be stopped at this time. In the initial stage of adding the flocculating agent, if the stirring is stopped, it is not conducive to the uniform mixing of the flocculating agent and the suspended particles in the grey water, resulting in uneven flocculation effect. Therefore, after stopping the introduction of carbon dioxide, the second driving rod 312 is retracted into the first stirring rod 314 under the driving of the spring 313, and by retracting the second driving rod 312 and the second stirring rod 315, the grey water can be stirred and the flocs can be prevented from being damaged.

[0048] Please refer to Figure 8 and ​ , the second stirring rod 315 is connected with a hollow guide rod 316, the outer wall of the guide rod 316 is provided with a threaded guide groove 3161, the second stirring rod 315 is provided with a bolt 317 matched with the guide groove 3161, the guide rod 316 is connected with an elastic rope 318, and the free end of the elastic rope 318 is fixedly connected with the first stirring rod 314. It should be noted that the thread needs to be set as a thread with large thread spacing, and the thread is set as half a circle, and a horizontal guide groove (not shown in the figure) is formed on the guide rod 316. The guide groove is communicated with the thread groove, so that the guide groove is first in contact with the bolt 317, and then the thread is in contact with the bolt 317, so that the guide rod can cooperate with the bolt 317, and the guide rod 316 is rotated by 90 degrees.

[0049] The specific working principle is as follows: when the first stirring rod 314 is connected with carbon dioxide and the motor 32 rotates to generate a centrifugal force, the guide rod 316 is pushed, and under the cooperation of the bolt 317, the guide rod 316 drives the second stirring rod 315 to move along the threaded track of the guide groove, so that the second stirring rod 315 rotates and extends out of the first stirring rod 314, and the spray hole 3151 faces upward. When the carbon dioxide is introduced, the second stirring rod 315 is extended and the spray hole 3151 faces upward, not only to increase the stirring area, but also because the second driving rod 312 and the first driving rod 311 are telescopic structures. When the gas is sprayed, the downward pressure on the second stirring rod 315 and the second driving rod 312 will make the second driving rod 312 more stably contact with the support seat 34.

[0050] After the carbon dioxide is stopped, the guide rod 316 is rotated 90 degrees under the action of the elastic rope 318, so that the nozzle 3151 is turned downward. After the carbon dioxide is stopped, the flocculating agent needs to be added to the water, in order to avoid the flocculation settling into the nozzle 3151 and causing the nozzle 3151 to be blocked. Therefore, the nozzle 3151 is turned downward. At this time, the second stirring rod 315 cannot be retracted into the first stirring rod 314, so as to avoid the stirring area being reduced, because the ash water still needs to be stirred. When the carbon dioxide and the ash water react for 1 hour, the reagent is added.

[0051] In order to better realize the above-mentioned waste heat boiler blowdown water recycling device, the application further provides a waste heat boiler blowdown water recycling method, which comprises the following steps:

[0052] Step S10: ash water introduction, starting the slurry pump 2 to introduce the ash water into the stirring tank 3, and preparing for the next step of stirring and reaction;

[0053] Step S20: carbon dioxide introduction, opening the connecting valve between the gas storage tank 4 and the stirring tank 3, introducing high-pressure carbon dioxide into the first driving rod 311 of the stirring tank 3 through the rotary joint of the gas storage tank 4, then sequentially passing through the second driving rod 312, the first stirring rod 314 and the second stirring rod 315, and finally being sprayed from the nozzle 3151 on the second stirring rod 315 into the ash water;

[0054] Step S30: stirring and reaction, starting the motor 32 to drive the stirring assembly 31 to rotate, generating centrifugal force, promoting the carbon dioxide bubbles to diffuse to the periphery of the stirring tank 3, increasing the contact area of the carbon dioxide bubbles with the ash water, and accelerating the gas dissolution process and the reaction rate;

[0055] Step S40: adjusting the bubbles, adjusting the distribution form of the bubbles in the ash water by periodically changing the rotating speed of the motor 32, realizing layered rising, prolonging the contact time of the gas with the ash water, and accelerating the dissolution and the reaction;

[0056] Step S50: adding reagent, adding the flocculating agent after the carbon dioxide and the ash water react for 1 hour;

[0057] Step S60: adjusting the stirring range, accelerating the stirring speed at the initial stage of adding the flocculating agent, promoting the mixing of the flocculating agent with the ash water, reducing the stirring intensity and retracting the second driving rod 312 and the stirring rod when the flocculation is observed at the bottom of the reaction tank, avoiding the destruction of the flocculation, and promoting the settlement of the flocculation;

[0058] Step S70: After the floe is settled, the sediment is discharged through the discharge port at the bottom of the stirring tank 3, the treated grey water is filtered or further purified, and after reaching the discharge standard, it is recovered or discharged.

[0059] The above is only an embodiment of the present application, and the common knowledge of specific structures and characteristics in the scheme is not described in detail. It should be pointed out that for those skilled in the art, without departing from the structure of the present application, a number of modifications and improvements can be made, which should also be considered as the protection scope of the present application, and these will not affect the effect and practicality of the patent. The protection scope claimed in the present application should be subject to the content of its claims, and the specific implementation mode and the like recorded in the specification can be used to explain the content of the claims.

Claims

1. A waste heat boiler blowdown water recovery device, comprising a boiler (1), a slurry pump (2), a mixing tank (3) and a gas storage tank (4) sequentially connected by pipelines from left to right, wherein the gas storage tank (4) is provided with carbon dioxide; the mixing tank (3) comprises a stirring assembly (31) arranged in the mixing tank (3) and a motor (32) for driving the stirring assembly (31); characterized in that, The stirring assembly (31) comprises: a first driving rod (311) in a hollow structure, connected with an output end of a motor (32), and communicated with the gas storage tank (4) through a rotary joint; a second driving rod (312) in a hollow structure, communicated with the first driving rod (311); a first stirring rod (314) in a hollow structure, in a number of two groups, and communicated with the first driving rod (311) and the second driving rod (312) respectively; a second stirring rod (315) in a hollow structure, slidingly arranged in the first stirring rod (314) and communicated with the first stirring rod (314), and provided with a plurality of spray holes (3151); the second driving rod (312) is slidingly arranged in the first driving rod (311) and connected with a spring (313) for resetting; the second stirring rod (315) is connected with a hollow guide rod (316), an outer wall of the guide rod (316) is provided with a threaded guide groove (3161), the second stirring rod (315) is provided with a bolt (317) matched with the guide groove (3161), the guide rod (316) is connected with an elastic rope (318), and a free end of the elastic rope (318) is connected with the first stirring rod (314).

2. A device for recovering blowdown water from a waste heat boiler according to claim 1, characterized in that: A sealing cover (33) is arranged on the top of the stirring tank (3).

3. A device for recovering blowdown water from a waste heat boiler according to claim 1, characterized in that: A supporting seat (34) matched with the second driving rod (312) is arranged in the stirring tank (3).

4. A device for recovering blowdown water from a waste heat boiler according to claim 1, characterized in that: The number of the first stirring rod (314) is a plurality, and the plurality of first stirring rods (314) are arranged along the axis of the first driving rod (311) in a circumferential direction.

5. A method for recovering blowdown water from a waste heat boiler, comprising the use of a device for recovering blowdown water from a waste heat boiler according to any one of claims 1 to 4, characterized in that The method comprises the following steps: Step S10: grey water introduction, starting a slurry pump to introduce the grey water into the stirring tank, and preparing for the next step of stirring and reaction; Step S20: carbon dioxide introduction, opening a connecting valve between the gas storage tank and the stirring tank, introducing high-pressure carbon dioxide into the first driving rod of the stirring tank through the rotary joint, then sequentially passing through the second driving rod, the first stirring rod and the second stirring rod, and finally spraying from the spray holes on the second stirring rod into the grey water; Step S30: stirring and reaction, starting the motor to drive the stirring assembly to rotate, generating a centrifugal force to promote the diffusion of carbon dioxide bubbles to the periphery of the stirring tank, increase the contact area of the carbon dioxide bubbles with the grey water, accelerate the gas dissolution process and the reaction rate; Step S40: adjusting the bubbles, adjusting the distribution form of the bubbles in the grey water by periodically changing the rotating speed of the motor, realizing layered rising, prolonging the contact time of the gas with the grey water, and accelerating the dissolution and reaction; Step S50: adding reagents, adding a flocculating agent after the carbon dioxide reacts with the grey water for 1 hour. Step S60: Adjust the stirring range, accelerate the stirring speed at the initial stage of flocculant addition to promote the mixing of flocculant and ash water, and reduce the stirring intensity and retract the second driving rod and stirring rod after observing the formation of floccus at the bottom of the reaction tank to avoid destroying the floccus and promote the settlement of the floccus; Step S70: After the settlement of the floccus, the sediment is discharged through the discharge port at the bottom of the stirring tank, and the treated ash water is discharged or recycled after reaching the discharge standard through filtration or further purification steps.

Images