Aluminum ash continuous pulping and alkaline dissolution production system

Abstract

The utility model provides an aluminum ash continuous pulping and alkaline dissolution production system, relates to the technical field of dangerous solid waste treatment, and solves the technical problem that the dissolution rate and the dissolution efficiency of aluminum ash are not effectively improved in the existing aluminum ash dissolution process. The device comprises a plurality of stages of alkali dissolution tanks used for reacting with aluminum ash to dissolve out gas, the alkali dissolution tanks comprise a first-stage alkali dissolution tank used for heating and dissolving the aluminum ash, and the first-stage alkali dissolution tank is communicated with a slurrying tank used for conveying aluminum ash slurry, an alkali liquor tank used for conveying alkali liquor and a steam pipe used for conveying heating steam. According to the utility model, continuous operation is realized, the production efficiency and the processing capacity are improved, and the shutdown time among batches is reduced; heat energy is effectively utilized, and the dissolution reaction temperature is increased, so that the reaction rate is increased, and the dissolution rate of aluminum oxide is increased; the byproducts of hydrogen, ammonia and methane are effectively utilized after being separated, and opportunities are provided for gas recovery and reutilization.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of dangerous solid waste treatment, and particularly relates to an aluminum ash continuous pulping and alkali method dissolution production system. BACKGROUND

[0002] Aluminum ash is the ash produced in the process of electrolytic aluminum or cast aluminum production, and belongs to dangerous solid waste. After decades of rapid development, China's aluminum industry has ranked first in the world for many years, providing strong support for the rapid development of the national economy. Currently, about 38 million tons of electrolytic aluminum are produced in China every year, and 10-13 kilograms of aluminum ash are produced per ton of electrolytic aluminum. Aluminum ash is easy to react in humid air to generate toxic, harmful, and explosive gases such as ammonia, methane, and hydrogen. Untreated aluminum ash can pollute the surrounding environment. Although many studies have been conducted on the comprehensive utilization of aluminum in aluminum ash over the years, many comprehensive utilization schemes have been proposed. However, due to the complex composition of aluminum ash, the utilization of any single target element cannot solve the economic and environmental problems. Therefore, how to efficiently recycle and dispose of aluminum ash is of great significance to China's aluminum industry and environmental protection.

[0003] Aluminum ash contains aluminum, aluminum oxide, aluminum carbide, silicon, fluoride, and chloride. Among them, aluminum oxide accounts for more than 70%, which has high recycling value. The currently widely used technology mainly includes wet disposal harmlessization or acid-alkali disposal harmlessization and resourceization. However, whether it is direct harmlessization using water or acid-alkali resourceization disposal of aluminum ash, aluminum ash will react with water, alkali, and acid to produce toxic and harmful gases and extremely explosive gases. There are great technical barriers and safety risk control difficulties in the disposal and utilization of aluminum ash.

[0004] Therefore, the patent with publication number CN114149017A proposes a method for continuous and stable operation of a one-stage dissolution process in the comprehensive utilization of aluminum ash, which realizes continuous operation of production and stable recovery and utilization of hydrogen energy. This method can avoid the entry of oxygen into the production system during the addition of aluminum ash, thereby avoiding the insecurity caused by the entry of oxygen. It also realizes the continuous feeding and discharging of aluminum ash, ensuring the continuous operation of the entire production process. However, the four-stage dissolution process of this device only prolongs the dissolution process and realizes continuous dissolution, but does not effectively improve the dissolution rate and dissolution efficiency of aluminum ash. UTILITY MODEL CONTENTS

[0005] The utility model aims to provide an aluminum ash continuous pulping and alkali method dissolution production system to solve the technical problem that the existing aluminum ash dissolution process does not effectively improve the dissolution rate and dissolution efficiency of aluminum ash.

[0006] The embodiments of the utility model realize the following technical solutions:

[0007] An aluminum ash continuous pulping and alkali leaching production system includes several stages of alkali leaching tanks for reacting and leaching gas with aluminum ash, the alkali leaching tank includes a primary alkali leaching tank for heating and dissolving aluminum ash, the primary alkali leaching tank is connected with a pulping tank for transporting aluminum ash slurry, an alkali tank for transporting alkali solution, and a steam pipe for transporting heating steam.

[0008] Preferably, the primary alkali leaching tank is also connected with an industrial water pipe for water replenishment.

[0009] Preferably, the pulping tank is also connected with the industrial water pipe for providing industrial water pulping, an aluminum ash bin for providing aluminum ash, and a sewage tank for replenishing pulping water.

[0010] Preferably, it also includes a gas-liquid separator for collecting the reaction and leaching gas of the alkali leaching tank and a buffer tank for collecting the leaching solution.

[0011] Preferably, the gas-liquid separator is also provided with a recycling pipe for recycling the separated leaching solution, and the recycling pipe is connected with the last stage of the alkali leaching tank.

[0012] Preferably, between several groups of the alkali leaching tank, several groups of connecting pipelines and control valves for controlling the liquid level are provided, and the liquid level of the alkali leaching tank is sequentially descending and consistent.

[0013] Preferably, the alkali leaching tank also includes a secondary alkali leaching tank, a tertiary alkali leaching tank, and a quaternary alkali leaching tank connected in sequence for gradually dissolving aluminum ash.

[0014] With this technical solution, the system is designed for continuous operation, improving production efficiency and processing capacity, and reducing batch downtime. By sending heating steam to the primary alkali leaching tank through the steam pipe, heat energy can be effectively utilized, the temperature of the leaching reaction can be increased, and the reaction rate can be accelerated and the leaching rate of aluminum oxide can be improved. The system includes an industrial water pipe for water replenishment and pulping, and a sewage tank for collecting and recycling pulping water, which helps to save water resources and reduce wastewater discharge. The gas-liquid separator is used to collect and separate the gas generated during the leaching process, which helps to improve the purity of the leaching solution and may provide opportunities for gas recycling and reuse. By providing connecting pipelines and control valves between the alkali leaching tanks, the liquid level can be accurately controlled to ensure a continuous and uniform leaching process. The system includes multiple stages of alkali leaching tanks, allowing the concentration or temperature of the alkali solution to be gradually increased to meet the needs of different stages of leaching, improving the efficiency of aluminum oxide extraction. The design of the pulping tank connected with the aluminum ash bin, alkali tank and steam pipe makes the material transportation more efficient, reducing the loss and pollution during material transfer. The system design takes into account the treatment of waste gas and wastewater, which helps to reduce environmental pollution and meets environmental protection requirements. By improving production efficiency and resource recovery rate, the system helps to reduce production costs and improve economic benefits.

[0015] The technical scheme of the embodiment of the utility model has at least the following advantages and beneficial effects:

[0016] 1. The utility model discloses continuous operation, improves production efficiency and processing capacity, reduces the batch between downtime;

[0017] 2. The utility model discloses effectively utilize heat energy, improve the temperature of dissolution reaction, thereby accelerate the reaction rate and improve the dissolution rate of alumina;

[0018] 3. The utility model discloses that hydrogen gas ammonia gas methane is effectively utilized after separating, provides the opportunity for the recovery and reuse of gas. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to make the technical scheme of the embodiment of the utility model clearer, the following will briefly introduce the drawing needed to be used in the embodiment, and it should be understood that the following drawings only show some embodiments of the utility model, and therefore should not be regarded as the limitation to the scope, and for the ordinary skilled person in the art, other related drawings can also be obtained according to these drawings without the creative labor.

[0020] Figure 1 The structure schematic diagram of the continuous pulping and alkali dissolution production system of aluminum ash for the embodiment 1 of the utility model is provided;

[0021] Figure 2 The structure schematic diagram of the continuous pulping and alkali dissolution production system of aluminum ash for the embodiment 2 of the utility model is provided;

[0022] Figure 3 The structure schematic diagram of the continuous pulping and alkali dissolution production system of aluminum ash for the embodiment 3 of the utility model is provided;

[0023] Figure: 1, aluminum ash bin;2, pulping tank;3, sewage tank;41, first-stage alkali dissolution tank;42, second-stage alkali dissolution tank;43, third-stage alkali dissolution tank;44, fourth-stage alkali dissolution tank;5, lye tank;6, buffer tank;7, gas-liquid separator;8, industrial water pipe;9, steam pipe. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the following will combine the drawing in the embodiment of the utility model, and the technical scheme in the embodiment of the utility model is described clearly and completely, obviously, the described embodiment is a part of the embodiment of the utility model, rather than all the embodiments. The components of the embodiment of the utility model described and shown in the drawing here can be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the application. Based upon the embodiments of the application, all other embodiments that would be obtained by one of ordinary skill in the art without having to make inventive efforts fall within the scope of the application.

[0026] It should be noted that like reference numerals and letters refer to like items in the several views of the drawings, and that, once an item is defined in one view, it need not be further defined and explained in the subsequent views.

[0027] In the description of the present application, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship of the product of the application when it is usually placed, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0028] In the description of the present application, it should also be noted that, unless otherwise explicitly specified and limited, if the terms "provision", "installation", "connection", "connection" appear, they should be understood in a broad sense, for example, they can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be connected inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0029] Embodiment 1

[0030] An aluminum ash continuous pulping and alkali dissolution production system, comprising a plurality of stages of alkali dissolution tanks for reacting and dissolving gas with aluminum ash, the alkali dissolution tank comprising a first-stage alkali dissolution tank 41 for heating and dissolving aluminum ash, the first-stage alkali dissolution tank 41 being communicated with a pulping tank 2 for conveying aluminum ash slurry, an alkali tank 5 for conveying alkali solution, and a steam pipe 9 for conveying heating steam.

[0031] In the present embodiment, the first-stage alkali dissolution tank 41 is also communicated with an industrial water pipe 8 for water replenishment.

[0032] In the present embodiment, the pulping tank 2 is also communicated with the industrial water pipe 8 for providing industrial water pulping, an aluminum ash bin 1 for providing aluminum ash, and a sewage tank 3 for replenishing pulping water.

[0033] In this embodiment, a gas-liquid separator 7 is also included to collect the reaction leaching gas from the alkali leaching tank, and a buffer tank 6 is used to collect the leaching solution.

[0034] In this embodiment, the gas-liquid separator 7 is also provided with a recycling pipe for recycling the separated leaching solution, which is connected to the last stage of the alkali leaching tank.

[0035] In this embodiment, a number of groups of connecting pipelines and control valves are provided between several groups of alkali leaching tanks to control the liquid level, and the liquid levels of the alkali leaching tanks are sequentially decreased.

[0036] In this embodiment, the alkali leaching tank also includes a second-stage alkali leaching tank 42, a third-stage alkali leaching tank 43, and a fourth-stage alkali leaching tank 44, which are sequentially connected to gradually dissolve the aluminum ash.

[0037] In this embodiment, the fourth-stage alkali leaching tank 44 is connected to the buffer tank 6.

[0038] Working principle and use method:

[0039] The system is designed for continuous operation, which improves production efficiency and processing capacity, and reduces downtime between batches. By delivering heated steam to the first-stage alkali leaching tank 41 through the steam pipe 9, the system can effectively utilize heat energy, increase the temperature of the leaching reaction, and thus accelerate the reaction rate and improve the leaching rate of alumina. The system includes an industrial water pipe 8 for water replenishment and pulp preparation, as well as a sewage tank 3 for collecting and reusing the pulp water, which helps to save water resources and reduce wastewater discharge. The gas-liquid separator 7 is used to collect and separate the gas generated during the leaching process, which helps to improve the purity of the leaching solution and may provide opportunities for gas recovery and reuse. By setting connecting pipelines and control valves between the alkali leaching tanks, the liquid level can be accurately controlled to ensure a continuous and uniform leaching process. The system includes multiple-stage alkali leaching tanks, which allow the concentration or temperature of the alkali solution to be gradually increased to adapt to the leaching requirements at different stages, improving the extraction efficiency of alumina. The design of the pulp tank 2 in communication with the aluminum ash bin 1, the alkali solution tank 5, and the steam pipe 9 makes the material transportation more efficient, reducing losses and pollution during the material transfer process. The system's design takes into account the treatment of waste gas and wastewater, which helps to reduce environmental pollution and meets environmental protection requirements. By improving production efficiency and resource recovery rate, the system helps to reduce production costs and improve economic benefits.

[0040] Example 2

[0041] The difference between this embodiment and Example 1 is that in this embodiment, the liquid levels of the alkali leaching tanks are consistent.

[0042] Example 3

[0043] The difference between the present embodiment and Embodiment 1 is that, in the present embodiment, the primary alkali elution solution tank 41, the secondary alkali elution solution tank 42, the tertiary alkali elution solution tank 43, and the quaternary alkali elution solution tank 44 are all connected to the buffer tank 6.

[0044] The above only is preferred embodiment of the present application, and is not used to limit the present application, for the person skilled in the art, the present application can have various changes and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A continuous production system for the production of alumina from spent potliner by digestion and caustic leaching, comprising a plurality of caustic leaching tanks for reaction with a leaching gas, characterised in that: The alkali leaching tank comprises a primary alkali leaching tank (41) for heating and dissolving aluminum ash, which is connected with a pulp tank (2) for delivering aluminum ash slurry, an alkali tank (5) for delivering alkali solution, and a steam pipe (9) for delivering heating steam.

2. The continuous production system of aluminum dross pulping and alkali dissolution according to claim 1, characterized in that: The primary alkali leaching tank (41) is also connected with an industrial water pipe (8) for water replenishment.

3. The continuous production system of aluminum dross pulping and alkali dissolution according to claim 2, characterized in that: The pulp tank (2) is also connected with the industrial water pipe (8) for providing industrial water pulp, an aluminum ash bin (1) for providing aluminum ash, and a sewage tank (3) for replenishing pulp water.

4. The continuous production system for pulping and alkali leaching of aluminum dross according to any one of claims 1-3, characterized in that: It also comprises a gas-liquid separator (7) for collecting the reaction leaching gas of the alkali leaching tank and a buffer tank (6) for collecting the leaching solution.

5. The continuous production system for producing alumina gray slurry and alkali dissolution according to claim 4, characterized in that: The gas-liquid separator (7) is also provided with a recycling pipe for recycling the separated leaching solution, which is connected with the last-stage alkali leaching tank.

6. The continuous production system for pulping and alkali leaching of aluminum dross according to any one of claims 1-3, characterized in that: A plurality of sets of the alkali leaching tanks are provided with a plurality of sets of connecting pipes and control valves for controlling the liquid level, and the liquid level of the alkali leaching tank is sequentially descending and consistent.

7. The continuous production system of alumina dregs slurry and alkali dissolution according to any one of claims 1-3, characterized in that: The alkali leaching tank also comprises a secondary alkali leaching tank (42), a tertiary alkali leaching tank (43), and a quaternary alkali leaching tank (44) connected in sequence for gradually dissolving aluminum ash. The alkali leaching tank also comprises a secondary alkali leaching tank (42), a tertiary alkali leaching tank (43), and a quaternary alkali leaching tank (44) connected in sequence for gradually dissolving aluminum ash.

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