Secondary aluminum ash treatment process

Abstract

The invention discloses a secondary aluminum ash treatment and recycling production process and equipment, and relates to the technical field of solid waste treatment.The equipment comprises a first reactor and a second reactor which are connected with each other, and the first reactor and the second reactor are both connected with an agent tank and a spray tower; the first reactor is connected with a gas storage tank through a first spray tower, the second reactor is connected to a chimney through a second spray tower, the first spray tower is connected with a liquid storage tank through a delivery pump, and the second reactor is connected with a crusher through a closed conveyor belt or a tunnel dryer. The technical problems that in the prior art, a secondary aluminum ash treatment method is simple and extensive, water is consumed, efficiency is low, energy consumption is large, waste gas and waste residues are generated, resource utilization cannot be achieved and the like can be solved, and the method has the advantages that harmlessness of the aluminum ash can be achieved, the method adapts to different types of aluminum ash, and the process additional value is higher.

Description

Technical Field

[0001] The invention relates to the technical field of solid waste treatment, and in particular to secondary aluminum ash treatment and resource production technology and equipment. Background Art

[0002] Secondary aluminum ash includes secondary aluminum ash and aluminum ash slag collected by bag dust removal. Secondary aluminum ash is the residue produced after primary aluminum ash is extracted and recycled and aluminum smelted with salt. It is mainly composed of aluminum, aluminum oxide and nitride, molten salt and other substances. Secondary aluminum ash from different regions and sources is different. Their aluminum content, aluminum nitride content and other compound content are different. The aluminum content of secondary aluminum ash is usually 10%~20%.

[0003] Aluminum ash has the dual characteristics of wasting resources and causing environmental harm. The harmful components in aluminum ash are mainly fluoride salts, chloride salts and nitrides. A large amount of aluminum nitride in aluminum ash has typical high permeability and high activity. It can react with water at room temperature to generate toxic, harmful and highly irritating gases, which will not only affect human health, but also cause air pollution. Substances such as chloride salts, fluoride salts and heavy metals in aluminum ash have certain leaching toxicity. These harmful elements can easily cause soil salinization and groundwater pollution when entering the soil. The particle size of aluminum ash is extremely fine, and it is easy to raise dust during storage, transportation and treatment, causing dust pollution.

[0004] Landfill is the traditional treatment method for aluminum ash. According to statistics, more than 90% of secondary aluminum ash is directly piled or landfilled without treatment. Some of them are treated by water washing and melting. Landfill is a low-cost method that does not require technical requirements. It is a traditional extensive treatment method that cannot fundamentally solve the problem. The water washing method is inefficient, and a set of treatment processes takes a lot of time. The treatment capacity of secondary aluminum ash is limited. In addition, the water consumption of the water washing method is relatively large, and the treatment of tail water after water washing usually consumes a lot of energy. The melting method requires the consumption of coking coal, which is extremely scarce in some countries and regions, and the coking process will produce a lot of pollution. If clean energy is used, its production cost is relatively high. The existing technology does not achieve the effective treatment and reuse of secondary aluminum ash, and cannot form a complete process chain and ecological chain. A large amount of waste gas and waste slag are still generated during the treatment process. The resource utilization degree of these waste gas and waste slag is very low, and it cannot bring added value. Summary of the invention

[0005] In view of the technical problems in the prior art that the secondary aluminum ash treatment methods are simple and extensive, water-consuming and inefficient, energy-intensive, generate waste gas and waste slag, and cannot be recycled, the present invention provides a secondary aluminum ash treatment and resource production process and equipment, which can achieve the harmlessness of aluminum ash, collect gas and ammonia water for reuse, and have higher process added value.

[0006] In order to solve the above technical problems, the technical solution provided by the present invention is: secondary aluminum ash processing equipment, comprising a first reactor and a second reactor connected to each other, the first reactor and the second reactor are both connected to a reagent tank and a spray tower, the first reactor is connected to a gas storage tank through a first spray tower, the second reactor is connected to a chimney through a second spray tower, the first spray tower is connected to a liquid storage tank through a delivery pump, and the second reactor is connected to a crusher through a closed conveyor belt or a tunnel dryer.

[0007] Optionally, the first reactor and the second reactor are connected via a closed conveyor belt, and there is at least one gas storage tank.

[0008] Optionally, the first reactor and the second reactor are both provided with cooling water channels, the closed conveyor belt is provided with a heat dissipation pipeline connected to the cooling water channels, and there is at least one liquid storage tank.

[0009] Optionally, a cooling heat exchanger is provided on the pipeline connecting the first reactor and the first spray tower, and the cooling heat exchanger is connected to the heat dissipation pipeline of the closed conveyor belt.

[0010] Optionally, the first reactor and the second reactor are both double-helix reactors, a horizontally mounted screw or paddle shaft is provided in the double-helix reactor, the screw or the paddle shaft is driven by a motor, an air outlet is provided at the top of the double-helix reactor, the air outlet is connected to the first spray tower, and the first reactor is connected to a feeder.

[0011] Optionally, both the first reactor and the second reactor are vertical stirred reactors with frame-type stirring paddles installed therein, the cooling water channel is a jacket, and the first reactor is connected to a feeder.

[0012] Optionally, the gas storage tank is connected to a gas generator set or a gas processing device, the first spray tower includes a spray tower 1 and a spray tower 2 connected in series, and the second spray tower includes a spray tower 3 and a spray tower 4 connected in series.

[0013] The present invention also provides a secondary aluminum ash treatment process, using the secondary aluminum ash treatment equipment, including opening the cooling water delivery of the cooling water channel of the first reactor, simultaneously delivering secondary aluminum ash and liquid alkali agent into the first reactor, opening the first spray tower and the second spray tower, the gas generated from the first reactor enters the first spray tower, the gas enters the gas storage tank after purification treatment in the first spray tower, the material discharged from the first reactor after a certain period of reaction is sent to the second reactor by a closed conveyor belt, and a catalyst is added to the second reactor at the same time, the gas generated by the second reactor enters the second spray tower, and the material discharged from the second reactor is conveyed to a crusher by a closed conveyor belt for crushing.

[0014] Optionally, the method further includes sending the liquid in the first spray tower to a liquid storage tank.

[0015] Optionally, the method further includes heating and drying the material discharged from the second reactor in a closed conveyor belt or a tunnel dryer, and the cooling water passing through the first reactor and the second reactor is sent to the heat dissipation pipe of the closed conveyor belt.

[0016] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0017] (1) Liquid alkali reagent can effectively consume aluminum nitride in secondary aluminum ash. The aluminum nitride in the treated secondary aluminum ash is greatly reduced. The secondary aluminum ash is no longer highly active and is in a stable state as a whole. It no longer reacts when it comes into contact with water and can meet the national environmental protection standards for building materials.

[0018] (2) Effectively reduce the content of chloride and chloride ions in secondary aluminum ash. The treated secondary aluminum ash contains a certain amount of sodium aluminate. Therefore, the treated secondary aluminum ash itself has high strength and is a good aggregate that can be used to make wall panels, unburned bricks and other building materials;

[0019] (3) A large amount of combustible gases are generated during the treatment of secondary aluminum ash: ammonia, hydrogen, and methane. Ammonia is absorbed by the spray tower to form ammonia water. The ammonia water produced can be used for desulfurization and denitrification, and can also be used for alkali production. Hydrogen and methane are then collected and utilized as resources and can be exported as industrial gas.

[0020] (4) The reactor suitable for slurry material reaction is used, which has higher processing efficiency and is suitable for different types of aluminum ash or secondary aluminum ash. The treated secondary aluminum ash is transported by a closed conveyor belt without gas leakage. The process is safe, environmentally friendly and pollution-free.

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more easily understood, some preferred embodiments are provided and described in detail as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of the secondary aluminum ash processing equipment proposed in an embodiment of the present invention.

[0023] Figure numerals: 1. No. 1 reagent tank; 2. First reactor; 3. No. 2 reagent tank; 4. Second reactor; 5. Crusher; 6. Aluminum ash storage tank; 7. No. 1 liquid storage tank; 8. No. 2 liquid storage tank; 9. Spray tower one; 10. Spray tower two; 11. Gas storage tank; 12. Spray tower three; 13. Spray tower four; 14. Chimney; 15. Gas generator set; 16. Gas processing equipment. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, an integral connection, or a detachable connection; it can be a mechanical connection or an electrical connection, or it can be the internal connection of two elements; it can be a direct connection, or it can be indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meaning of the terms can be understood according to the specific circumstances.

[0026] The embodiment of the present invention discloses a secondary aluminum ash processing device, such as Figure 1 As shown, it includes a first reactor and a second reactor connected to each other, and the first reactor and the second reactor are both connected to a medicine tank and a spray tower. The medicine tanks are respectively No. 1 medicine tank and No. 2 medicine tank, which are respectively filled with different medicines; the first reactor is connected to a gas storage tank through a first spray tower, and the gas storage tank is a dome vertical storage tank, and there is at least one gas storage tank; the second reactor is connected to a chimney through a second spray tower, and the first spray tower is connected to a liquid storage tank through a delivery pump, and there are two liquid storage tanks, namely No. 1 liquid storage tank and No. 2 liquid storage tank; the second reactor is connected to a crusher through a closed conveyor belt or a tunnel dryer. The crusher is connected to an aluminum ash storage depot through a conveyor belt, and the aluminum ash slag is packaged for standby use. The first reactor and the second reactor are connected by a closed conveyor belt, and the gas pipeline connected between the first reactor and the first spray tower passes through the closed conveyor belt, and the gas pipeline is provided with heat dissipation fins. Since the secondary aluminum ash releases heat during the reaction with the liquid alkali agent, the gas temperature in the gas pipeline is relatively high. This heat can be used to heat the materials transported in the closed conveyor belt, thereby achieving the effect of energy saving and drying the materials.

[0027] The first reactor and the second reactor are both provided with cooling water channels, and the closed conveyor belt is provided with a heat dissipation pipeline connected with the cooling water channels. A cooling heat exchanger is provided on the pipeline connecting the first reactor and the first spray tower, and the cooling heat exchanger is connected with the heat dissipation pipeline of the closed conveyor belt.

[0028] In one embodiment, the first reactor and the second reactor are both vertical stirred reactors, each of which is provided with a frame-type stirring paddle driven by a motor, the cooling water channels on the first reactor and the second reactor are jacketed, the first reactor is connected to a feeder, and a pressure relief valve is provided on the first reactor and the second reactor.

[0029] In another embodiment, the first reactor and the second reactor are both double-helix reactors, a horizontally mounted screw or paddle shaft is provided in the double-helix reactor, the screw or paddle shaft is driven by an explosion-proof motor, an air outlet is provided at the top of the double-helix reactor, a pressure relief valve is also provided on the air outlet, the air outlet is connected to the first spray tower, and the first reactor is connected to a feeder.

[0030] The gas storage tank is connected to the gas generator set or gas processing equipment. The first spray tower includes spray tower 1 and spray tower 2 connected in series. Spray tower 1 and spray tower 2 are both equipped with pressure relief valves. The lower parts of spray tower 1 and spray tower 2 are both equipped with ammonia concentration detectors. When the ammonia concentration reaches the threshold, the branch is opened to send ammonia to the liquid storage tank. The delivery pump of the spray tower is connected to the liquid inlet at the top of the spray tower. The delivery pump is also connected to the liquid storage tank. When the liquid level in the spray tower drops to the preset level, industrial water is added to the spray tower. The second spray tower includes spray tower 3 and spray tower 4 connected in series. The exhaust port of spray tower 4 is equipped with a gas concentration detector to monitor the components of the exhaust gas in real time to achieve standard emissions. If the standard is exceeded, an alarm will be sent to the equipment operation console.

[0031] The present invention also provides a secondary aluminum ash treatment process, using the secondary aluminum ash treatment equipment, including opening the cooling water delivery of the cooling water channel of the first reactor, and simultaneously delivering the secondary aluminum ash and the liquid alkali agent into the first reactor, the main component of the liquid alkali agent is a sodium hydroxide solution or a caustic soda solution, and the liquid agent can be sent into the reactor by a pipeline, opening the first spray tower and the second spray tower, the gas generated from the first reactor enters the first spray tower, the gas enters the gas storage tank after being purified by the first spray tower, the material discharged after a certain period of reaction in the first reactor is sent to the second reactor by a closed conveyor belt, and a catalyst is added to the second reactor at the same time, the catalyst is one or more of sulfuric acid, calcium carbonate or sodium carbonate, the gas generated by the second reactor enters the second spray tower, and the material discharged from the second reactor is conveyed to the crusher by a closed conveyor belt for crushing. When the liquid concentration in the first spray tower reaches the threshold value, the liquid in the first spray tower is automatically sent to the liquid storage tank. When the gas concentration at the exhaust port of the spray tower four in the second spray tower exceeds the standard, the gas generated by the second reactor is sent to the emergency water pool, and the feeding operation of the first reactor is suspended.

[0032] The material discharged from the second reactor is heated and dried in a closed conveyor belt or tunnel dryer, and the cooling water passing through the first and second reactors is sent to the heat dissipation pipe of the closed conveyor belt. This reduces the moisture content of the treated secondary aluminum ash before entering the crusher, and also utilizes the reaction heat generated by the secondary aluminum ash treatment. The gas generated by the first reactor is cooled before entering the spray tower 1, which improves the absorption effect of the gas in the spray tower.

[0033] The present invention and its implementation methods are described schematically above, and the description is not restrictive. Therefore, if a person skilled in the art is inspired by the description and creatively designs a structure and implementation method similar to the technical solution without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. Secondary aluminum ash treatment process, characterized in that: The secondary aluminum ash treatment equipment is used, including opening the cooling water channel of the first reactor to deliver cooling water, The secondary aluminum ash processing equipment comprises a first reactor and a second reactor which are connected to each other, the first reactor and the second reactor are both connected to a reagent tank and a spray tower, the first reactor is connected to a gas storage tank through the first spray tower, the second reactor is connected to a chimney through the second spray tower, the first spray tower is connected to a liquid storage tank through a delivery pump, and the second reactor is connected to a crusher through a closed conveyor belt or a tunnel dryer; The first reactor and the second reactor are connected by a closed conveyor belt, and there is at least one gas storage tank; The first reactor and the second reactor are both provided with cooling water channels, the closed conveyor belt is provided with a heat dissipation pipeline connected with the cooling water channels, and there is at least one liquid storage tank; A cooling heat exchanger is provided on the pipeline connecting the first reactor and the first spray tower, and the cooling heat exchanger is communicated with the heat dissipation pipeline of the closed conveyor belt; The first reactor and the second reactor are both double-helix reactors, a horizontally mounted screw or blade shaft is provided in the double-helix reactor, the screw or the blade shaft is driven by a motor, an air outlet is provided at the top of the double-helix reactor, the air outlet of the first reactor is connected to the first spray tower, the air outlet of the second reactor is connected to the second spray tower, and the first reactor is connected to a feeder; The gas storage tank is connected to a gas generator set or a gas processing device. The first spray tower includes spray tower one and spray tower two connected in series. The lower parts of spray tower one and spray tower two are both provided with ammonia concentration detection. When the ammonia concentration reaches a threshold, a branch line is opened to send the ammonia to the liquid storage tank. The delivery pump of the spray tower is connected to the liquid inlet at the top of the spray tower.

2. The secondary aluminum ash treatment process according to claim 1, characterized in that: Secondary aluminum ash and liquid alkali agent are conveyed into the first reactor at the same time, the first spray tower and the second spray tower are opened, the gas generated from the first reactor enters the first spray tower, the gas enters the gas storage tank after purification treatment in the first spray tower, the material discharged from the first reactor after a certain period of reaction is conveyed into the second reactor by a closed conveyor belt, and the catalyst is added to the second reactor at the same time, the gas generated in the second reactor enters the second spray tower, and the material discharged from the second reactor is conveyed to the crusher by a closed conveyor belt for crushing.

3. The secondary aluminum ash treatment process according to claim 1, characterized in that: The delivery pump is connected to the liquid storage tank.

4. The secondary aluminum ash treatment process according to claim 1, characterized in that: The second spray tower includes a spray tower three and a spray tower four which are connected in series.

5. The secondary aluminum ash treatment process according to claim 1, characterized in that: A gas concentration detector is installed at the exhaust port of spray tower 4 to monitor the composition of the exhaust gas.

6. The secondary aluminum ash treatment process according to claim 1, characterized in that: The motor is an explosion-proof motor.

7. The secondary aluminum ash treatment process according to claim 1, characterized in that: The method also includes heating and drying the material discharged from the second reactor in a closed conveyor belt or a tunnel dryer, and the cooling water passing through the first reactor and the second reactor is sent to the heat dissipation pipeline of the closed conveyor belt.

8. The secondary aluminum ash treatment process according to claim 1, characterized in that: The first reactor and the second reactor are both provided with pressure relief valves.

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