The main components of aluminum ash are metallic aluminum and alumina, in which the content of metallic aluminum can reach 10-70%. The National Catalogue of Hazardous Wastes (202 1 Edition) classifies the aluminum ash produced by electrolytic aluminum, recycled aluminum, aluminum processing and dust collection in detail, and distinguishes the dangerous characteristics of aluminum from different processes. Among them, aluminum ash produced by electrolytic aluminum and salt slag and aluminum ash produced in aluminum recovery process have dangerous characteristics of reactivity and leaching toxicity, while aluminum ash produced by recycled aluminum and aluminum processing and salt slag and aluminum ash produced in aluminum recovery process have dangerous characteristics of reactivity.
China produces more than 2 million tons of aluminum ash every year. After aluminum ash is defined as hazardous waste, the traditional extensive treatment method is no longer feasible. At present, there is a lack of advanced, mature and efficient secondary aluminum ash treatment technology. Secondary aluminum ash has low aluminum content, complex impurity composition and high treatment cost, so it is difficult to be comprehensively utilized. At present, the problems existing in the disposal of aluminum ash and how to make use of aluminum ash as resources have become the problems facing and facing squarely in China's aluminum industry.
The characteristics of aluminum ash are reflected in three aspects: 1, toxic activity and hazardous waste; 2, the quantity is large, and the national annual emission is several million tons; 3. It contains metallic aluminum, aluminum compounds and heat energy, and has high potential value.
Domestic primary aluminum ash has been paid attention to and recycled by enterprises because of its high aluminum content and great economic value. The potential value of aluminum ash is mainly reflected in its metal aluminum, alumina and its heat energy. However, the secondary aluminum ash, as the residue after extracting aluminum from primary aluminum ash, was abandoned or buried because of the lack of mature technology, low economic investment and high efficiency disposal projects in China before the implementation of environmental protection tax, which not only wasted resources, but also polluted the environment, which was extremely disproportionate to the current concept of green development. Judging from the nature, composition and potential value of secondary aluminum ash, the key to the resource utilization of aluminum ash lies in secondary aluminum ash. Therefore, the times call for the popularization of disposal technology with mature technology, low economic investment and high efficiency as soon as possible.
In view of the present situation and shortcomings of secondary aluminum ash resource utilization, in order to realize the recycling of aluminum elements in secondary aluminum ash in the production process of aluminum smelting or aluminum processing enterprises, Guangzhou Paian Environmental Protection Technology Co., Ltd. has developed a new technology for secondary aluminum ash resource utilization, which not only ensures safety and environmental protection, but also greatly reduces the disposal cost of secondary aluminum ash.
Resource utilization of wet-process aluminum ash in Paian, Guangzhou
Process introduction:
The aluminum ash is separated and screened by ball milling in the early stage, and then enters the primary reaction kettle. Soluble ammonia in aluminum ash is quickly converted into gaseous ammonia (ammonia) by deamination agent and catalyst, and filtered once by circulating reaction, and the produced filter mud is pressed into bricks (the addition of aluminum ash is 20%, supplemented by cement and yellow sand, etc.). ). Ammonia gas produced in the first two reactions is neutralized with sulfuric acid (concentration is 95%) to form ammonium sulfate, and the filtrate produced in the process is collected.
Process analysis:
A, the production cost is about 1200 yuan/ton, and the investment cost is about 1000 yuan/ton.
B, the hydrolysis reaction process takes a long time, about 2 hours/kettle, and the temperature is about 80℃
C, products after the reaction: heavy metals, purity of ammonium sulfate, hydrogen content in ammonia gas, safe saturated concentration of wastewater recovery crystals and other issues to be further solved.
Guangzhou Paian Environmental Protection Technology Co., Ltd. specializes in the research, development, application and promotion of dioxin disposal technology in flue gas and secondary recycling technology of aluminum ash, involving various hazardous waste solid waste disposal industries such as garbage power plants, smelters and aluminum mold factories. The founder of the company has more than 25 years of experience in environmental protection disposal industry, and has unique technologies and patents in flue gas dioxin disposal, secondary aluminum ash recycling and other aspects, as well as industry application cases, which are trustworthy. The company is good at waste recycling technology. Its founder has more than 25 years of experience in environmental protection. When applied to the recycling technology of recycled aluminum ash, the investment cost is low and the scale is operable. Welcome to contact the website for communication.