A method for safe and harmless treatment of aluminum ash

A technology of harmless treatment and aluminum ash, which is applied in the field of recycling and utilization of aluminum ash, which is a waste resource in the aluminum industry, can solve the problems of high evaporation cost, product sales and use, and excessive reaction of ammonia gas, so as to improve the production safety factor and release The effect of smooth mitigation and control of explosion risk

Active Publication Date: 2020-12-01
湖南绿脉环保科技股份有限公司
View PDF4 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] For example, the patent document with the application number 201710634163.9 discloses a high-efficiency AlN hydrolysis recovery process and its device in aluminum ash, and the patent document with the application number 201810373362.3 discloses an aluminum ash ammonia resource recycling device, application number The patent document of 201710893673.8 discloses a method of pressure regulation-hydrothermal swirling process to strengthen the denitrification of aluminum ash. The above-mentioned schemes all use wet process to process aluminum nitride, although ammonia gas can be absorbed and However, due to the slow hydrolysis rate of aluminum nitride at room temperature, the treatment process has a long-lasting impact on the environment and is very harmful, and the concentration of ammonia water produced is low, so it cannot be directly used as a product for sale
[0005] Patent No. 201510808471.X discloses a comprehensive utilization treatment method for aluminum ash, which discloses the catalytic hydrolysis technology of aluminum nitride, that is, by adding a catalyst for catalytic deamination, it can be quickly decomposed to produce ammonia gas, which can effectively Solve the problem of continuous environmental impact of aluminum ash deamination process
However, in the actual production process, it is found that the rapid decomposition of ammonia gas may cause risks such as explosion, so it is necessary to control the risk of explosion
At the same time, because the ammonia gas will bring out a large amount of water when the aluminum ash slurry reacts, the ammonia gas concentration is too low
If the ammonia gas is concentrated by evaporation, the cost of evaporation will be too high
[0006] Based on the above reasons, it is necessary to provide a safe and harmless method for the treatment of aluminum ash, which can solve the problem of excessive ammonia gas reaction in the process of aluminum ash deamination, prevent the risk of explosion, and effectively solve the problem of excessive ammonia gas concentration. low problem

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] The raw material of aluminum ash to be processed: the mass percentage of moisture is 3%, and the mass percentage of aluminum nitride is 18%.

[0032]Put 130kg of aluminum ash raw material into the silo, put it into the rotary cylinder of the primary deamination device through the screw feeder, turn on the rotary motor, and the rotation speed is 1.5r / min. The mixed gas of ammonia and water vapor (ammonia volume concentration is 6%) is contacted for heat exchange, and the aluminum nitride initially reacts with water vapor and decomposes into ammonia gas. After a deammonization treatment, the concentration of ammonia gas collected increases. To 22% (volume percent concentration), the aluminum nitride content in the raw aluminum ash is reduced from 18% to 14%, and the moisture content of the aluminum ash increases to 7%.

[0033] Add 1.3 tons of tap water at 85°C to the slurry tank, and add aluminum ash after a deammonization treatment. Under the action of stirring, the alu...

Embodiment 2

[0037] The raw material of aluminum ash to be processed: the mass percentage of moisture is 1%, and the mass percentage of aluminum nitride is 48%.

[0038] Put 200kg aluminum ash raw material to be processed into the silo, and add it into the circulating fluidized bed through the screw feeder. During the falling process, the raw material is mixed with ammonia and water vapor from the pulping process and the catalytic deamination process (ammonia Gas volume concentration is 3%) for contact, heat exchange, aluminum nitride initially reacts with water vapor and decomposes into ammonia gas, after a deammonization treatment, the ammonia gas concentration in the gas is increased to 50% (volume percentage concentration), the raw material The aluminum nitride content in aluminum ash was reduced from 48% to 36%, and the moisture content in aluminum ash was increased to 8%.

[0039] Add tap water at 65°C in the slurry tank at a liquid-solid ratio of 5:1, and under stirring, the aluminu...

Embodiment 3

[0043] The raw material of aluminum ash to be processed: the mass percentage of moisture is 1%, and the mass percentage of aluminum nitride is 8%.

[0044] 400kg of aluminum ash is loaded into the silo and added to the vibrating fluidized bed through a screw feeder. During the falling process, the raw material is mixed with ammonia and water vapor from the pulping process and catalytic deamination process (ammonia volume concentration 5%) for contact, heat exchange, aluminum nitride initially reacts with water vapor and decomposes into ammonia, after a deammonization treatment, the ammonia concentration in the gas is increased to 22% (volume percentage concentration), and the The aluminum nitride content is reduced from 8% to 6%, and the aluminum ash moisture content is increased to 5%.

[0045] Add 40kg of 65°C tap water into the slurry tank at a liquid-to-solid ratio of 1:10. Under stirring, the aluminum nitride in the aluminum ash will continue to contact with hot water for...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to the technical field of recycling of aluminum industry waste resource aluminum ash, and discloses a safe harmless aluminum ash treatment method. According to the safe harmlessaluminum ash treatment method, aluminum ash is subjected to staged treatment, namely, primary deamination treatment, pulping and secondary deamination, and catalytic deamination, aluminum nitride in aluminum ash is decomposed by stages, ammonia gas is generated, release of ammonia gas is smooth, concentration of ammonia gas is controlled out of the explosion limit range, and the production safetycoefficient of an aluminum ash treatment system is improved; and the water content of ammonia gas generated during the pulping and secondary deamination, and catalytic deamination processes is high, concentration of ammonia gas is low, vapor containing ammonia gas is generated, vapor containing ammonia gas is collected and sent to the primary deamination treatment process and is adopted as a reaction raw material of aluminum ash primary deamination, high-concentration ammonia gas is obtained through treatment, the problem that concentration of ammonia gas generated through aluminum ash deamination is too low is effectively solved, and evaporation concentration cost of ammonia gas is eliminated.

Description

technical field [0001] The invention relates to the technical field of recycling aluminum ash as a waste resource in the aluminum industry, in particular to a method for safe and harmless treatment of aluminum ash. Background technique [0002] Aluminum ash is a product produced in the production of electrolytic aluminum, aluminum processing or casting aluminum. It is mainly derived from infusible inclusions, oxides, additives, and reaction products produced by physical and chemical reactions with additives floating on the surface of aluminum melt during the production process of smelting aluminum and aluminum alloys. It is produced in all production processes where aluminum is melted. process. Aluminum ash contains aluminum and various valuable elements, mainly composed of metal aluminum (5-70%), aluminum nitride (10-50%), aluminum oxide (20-40%), other metal oxides (2-10%) %) and salt flux (2-30%). According to the different aluminum content, aluminum ash can be divided...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): B09B3/00C01C1/02
CPCB09B3/00C01C1/026
Inventor 梁文强谢雪梅唐剑李湘花陈湘清陈小松陈黎军周贤明
Owner 湖南绿脉环保科技股份有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap