A device for washing and carbonation of household waste incineration fly ash

Abstract

The utility model discloses a kind of domestic waste incineration fly ash washing carbonation device, comprising: reaction tank, high-efficiency cyclone aerator and agitator, agitator is set to the upper end of reaction tank, the lower end of agitator is inserted into reaction tank, high-efficiency cyclone aerator is set on the inside bottom wall of the both sides of reaction tank, the side of reaction tank is provided with slurry inlet, the other side of reaction tank is provided with slurry outlet. Through the application of the utility model, a kind of domestic waste incineration fly ash washing carbonation device is presented, which is carbonated by using the slurry formed after dissolving fly ash with carbon dioxide, not only can effectively improve the removal rate of chlorides in fly ash, so that chlorides removal is more thorough, but also can avoid the case of using a large amount of hydrochloric acid to adjust PH value, which is beneficial to reduce the secondary pollution risk caused by the use of hydrochloric acid;In addition, a large amount of calcium minerals will also be dissolved in the process of carbonating slurry, which is beneficial to improve the utilization rate of calcium resources in fly ash.

Description

Technical Field

[0001] This utility model relates to the field of waste treatment equipment technology, and in particular to a device for washing and carbonating fly ash from municipal solid waste incineration. Background Technology

[0002] With the acceleration of urbanization and the improvement of people's living standards in my country, the volume of municipal solid waste collection continues to rise. Simultaneously, the proportion of incineration in waste treatment is also increasing, leading to explosive growth in the waste incineration industry. During waste incineration, various harmful substances are generated, such as dioxins, acidic gases (hydrogen chloride, sulfur dioxide, etc.), nitrogen oxides, heavy metals, and dust. During flue gas purification, most of these pollutants are trapped by dust removal systems, forming fly ash. Water washing, as a crucial step in fly ash treatment, aims to dissolve chloride salts in the fly ash and reduce its chlorine content. This is of great significance for the harmless and resource-based treatment of fly ash and is an indispensable step in the fly ash resource utilization process.

[0003] To address the issue of high levels of insoluble chloride salts in fly ash and the difficulty of achieving adequate standards through simple water washing, existing technologies often employ deep washing, which involves adding large amounts of hydrochloric acid to adjust the pH value, thereby dissolving and extracting Ca ions. However, this approach has several drawbacks: First, it consumes a large amount of hydrochloric acid, increasing processing costs and posing safety risks during storage and transportation. Second, adding hydrochloric acid increases the burden of chloride ion removal in subsequent processes, making subsequent treatment more difficult. Furthermore, the loss of significant amounts of Ca ions reduces the utilization rate of fly ash resources, hindering effective recovery and reuse. Utility Model Content

[0004] In view of this, in order to solve the above problems, the purpose of this utility model is to provide a water washing and carbonation device for fly ash from municipal solid waste incineration, comprising: a reaction tank, a high-efficiency cyclone aerator and a stirrer, wherein the stirrer is disposed at the upper end of the reaction tank and the lower end of the stirrer extends into the reaction tank, the high-efficiency cyclone aerator is disposed on the inner bottom wall of both sides of the reaction tank, a slurry inlet is provided on one side of the reaction tank and a slurry outlet is provided on the other side of the reaction tank.

[0005] In another preferred embodiment, the high-efficiency cyclone aerator is connected to an external CO2 gas source, and CO2 enters the high-efficiency cyclone aerator from the top of the reaction tank.

[0006] In another preferred embodiment, the system further includes a baffle plate disposed on the other side of the reaction vessel, the upper end of the baffle plate being connected to the upper inner wall of the reaction vessel, and the baffle plate being close to the slurry outlet.

[0007] In another preferred embodiment, the system further includes a pH meter, which is disposed on the other side of the reaction vessel, with its lower end extending into the reaction vessel.

[0008] In another preferred embodiment, the system further includes a control system, wherein the pH meter, the high-efficiency cyclone aerator, and the agitator are all connected to the control system.

[0009] In another preferred embodiment, a solenoid valve is installed on the pipeline between the CO2 gas source and the high-efficiency cyclone aerator, and the solenoid valve is connected to the control system.

[0010] The present invention, by adopting the above-mentioned technical solution, has the following positive effects compared with the prior art: Through the application of the present invention, a water-washing and carbonation device for municipal solid waste incineration fly ash is proposed. This device utilizes carbon dioxide to carbonate the slurry formed after the fly ash is dissolved. This not only effectively improves the removal rate of chloride salts in the fly ash and further promotes the conversion and dissolution of insoluble chloride salts, resulting in more thorough chloride salt removal, but also avoids the need for large-scale use of hydrochloric acid to adjust the pH value, thus reducing the risk of secondary pollution caused by hydrochloric acid use. Furthermore, a large amount of calcium minerals dissolve during the carbonation process of the slurry. This not only helps to prevent calcium mineral deposition and blockage, ensuring normal equipment operation, but also improves the utilization rate of calcium resources in the fly ash, which is beneficial for the resource utilization of fly ash. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of a municipal solid waste incineration fly ash washing and carbonation device according to the present invention.

[0012] In the attached image:

[0013] 1. Reaction tank; 2. High-efficiency cyclone aerator; 3. Agitator; 4. pH meter; 5. Baffle; 11. Slurry inlet; 12. Slurry outlet. Detailed Implementation

[0014] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0015] In the description of this utility model, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "front", "back", "horizontal", and "vertical" are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0016] It should be noted that the terms "horizontal" and "vertical" in this utility model are used to describe approximate positional relationships, and not strictly "horizontal plane" or "vertical plane".

[0017] like Figure 1 The diagram illustrates a preferred embodiment of a municipal solid waste incineration fly ash washing and carbonation device, comprising: a reaction tank 1, a high-efficiency cyclone aerator 2, and a stirrer 3. The stirrer 3 is positioned at the upper end of the reaction tank 1, with its lower end extending into the tank. High-efficiency cyclone aerators 2 are installed on the inner bottom walls of both sides of the reaction tank 1. A slurry inlet 11 is located on one side of the reaction tank 1, and a slurry outlet 12 is located on the other side. Furthermore, when the slurry reacts fully with carbon dioxide, the stirrer 3 ensures a more complete reaction and prevents scaling problems such as calcium carbonate precipitation, thus facilitating the normal operation of the equipment.

[0018] Furthermore, as a preferred embodiment, the high-efficiency cyclone aerator 2 is connected to an external CO2 gas source, and CO2 enters the high-efficiency cyclone aerator 2 from the top of the reaction tank 1.

[0019] Furthermore, as a preferred embodiment, it also includes a baffle 5, which is disposed on the other side of the reaction tank 1. The upper end of the baffle 5 is connected to the upper inner wall of the reaction tank 1, and the baffle 5 is close to the slurry outlet 12. Furthermore, the baffle 5 can provide preliminary filtration and buffering for the flowing slurry, and can block larger particles of impurities and fly ash agglomerates, making the outflowing slurry more uniform and stable, which is beneficial for subsequent processing steps.

[0020] Furthermore, as a preferred embodiment, it also includes a pH meter 4, which is disposed on the other side of the reaction tank 1, with its lower end extending into the reaction tank 1. Further, the pH meter 4 is used to monitor the acidity or alkalinity of the slurry in real time and transmit this data to the control system in real time. Subsequently, the control system can precisely regulate the amount of CO2 gas entering the high-efficiency cyclone aerator 2 by controlling a solenoid valve based on the received pH information, thereby avoiding incomplete reaction due to insufficient carbon dioxide in the reaction tank 1 or scaling due to excessive carbon dioxide.

[0021] Furthermore, as a preferred embodiment, it also includes: a control system, wherein the pH meter 4, the high-efficiency cyclone aerator 2 and the agitator 3 are all connected to the control system.

[0022] Furthermore, as a preferred embodiment, the control system is preferably configured as a PLC controller commonly used in the prior art, therefore the control system will not be described in detail here.

[0023] Furthermore, as a preferred embodiment, a solenoid valve is installed on the pipeline between the CO2 gas source and the high-efficiency cyclone aerator 2, and the solenoid valve is connected to the control system.

[0024] The working principle of this utility model is as follows: When treating fly ash, the fly ash is first transported from the original ash silo to the fly ash buffer silo, and after metering, it is then transported to the front-end dissolving tank. In the front-end dissolving tank, water is used to wash and dissolve the fly ash, so that the fly ash and water are mixed in the front-end dissolving tank at a ratio of approximately 1:4 (mass ratio) to form a slurry. This one-time water washing and dewatering method can avoid the generation of insoluble chloride salts from multiple water washings. After washing and dissolving, the slurry is transported to the reaction tank 1 through the slurry inlet 11 by a transfer pump. After the slurry enters the reaction tank 1, the CO2 gas source can supply CO2 gas into the reaction tank 1. The CO2 enters the high-efficiency cyclone aerator 2 from the top of the reaction tank 1. Subsequently, the high-efficiency cyclone aerator 2 causes the carbon dioxide gas to react with the slurry in the reaction tank 1 in a cyclone manner. The liquid comes into intense contact and collides with the slurry. At the same time, the agitator 3 can stir the slurry so that the carbon dioxide gas can fully react with the slurry, thereby reducing the pH value of the slurry and controlling the pH value of the slurry within the range of 8.5-9. After sufficient reaction, the slurry can flow out from the slurry outlet 12 and enter the subsequent dewatering and filtration stage. The slurry flowing out from the slurry outlet 12 is pressed into the filter chamber of the filter press by a pressure pump, and the slurry is filtered and pressed through the filter screen of the filter press. The filtered filtrate is discharged to the front-end dissolving tank to wash and dissolve the fly ash, thereby realizing the recycling of the filtrate. The pressed ash cake remains in the filter chamber and is rinsed with clean water to achieve further dechlorination. After washing, it is pressed and dried a second time, at which point the dechlorinated ash cake can be obtained.

[0025] The above description is only a preferred embodiment of the present utility model and does not limit the implementation method and protection scope of the present utility model. Those skilled in the art should realize that all solutions obtained by equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A device for washing and carbonating fly ash from municipal solid waste incineration, characterized in that, include: The reaction vessel includes a high-efficiency cyclone aerator and a stirrer. The stirrer is located at the upper end of the reaction vessel, and its lower end extends into the reaction vessel. The high-efficiency cyclone aerator is installed on the inner bottom wall of both sides of the reaction vessel. A slurry inlet is opened on one side of the reaction vessel, and a slurry outlet is opened on the other side of the reaction vessel.

2. The municipal solid waste incineration fly ash washing and carbonation device according to claim 1, characterized in that, The high-efficiency cyclone aerator is connected to an external CO2 gas source, and CO2 enters the high-efficiency cyclone aerator from the top of the reaction tank.

3. The municipal solid waste incineration fly ash washing and carbonation device according to claim 1, characterized in that, Also includes: A baffle is provided on the other side of the reaction vessel, with its upper end connected to the upper inner wall of the reaction vessel and the baffle being close to the slurry outlet.

4. The municipal solid waste incineration fly ash washing and carbonation device according to claim 2, characterized in that, Also includes: A pH meter is provided, located on the other side of the reaction vessel, with its lower end extending into the reaction vessel.

5. The municipal solid waste incineration fly ash washing and carbonation device according to claim 4, characterized in that, Also includes: The control system is connected to the pH meter, the high-efficiency cyclone aerator, and the agitator.

6. The municipal solid waste incineration fly ash washing and carbonation device according to claim 5, characterized in that, A solenoid valve is installed on the pipeline between the CO2 gas source and the high-efficiency cyclone aerator, and the solenoid valve is connected to the control system.

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