Environmental protection and energy saving short process casting aluminum alloy production process

Abstract

The invention discloses an environment-friendly and energy-saving short-flow casting aluminum alloy production process, which includes the following steps: the first step is to prepare an aluminum alloy solution by alloying in a vacuum bag; the second step is to complex the aluminum alloy solution in a low-level furnace using fluorine salts The aluminum alloy refining agent is refined and prepared to obtain an aluminum alloy solution to be poured; in the third step, the aluminum alloy solution to be poured is cast to obtain an aluminum alloy ingot. The invention saves the natural gas heating energy needed for preheating the high-level furnace and alloying the temperature after adding aluminum, and greatly reduces the production energy consumption; compared with the existing aluminum alloy production process, the production time is optimized from about 5 hours to about 3 One furnace per hour greatly improves production efficiency; reduces raw material and labor costs; solves the problem of using chlorine salt as a refining agent to produce aluminum ash that cannot be recycled, and further saves the cost of non-recyclable aluminum ash treatment.

Description

Technical field: [0001] The invention relates to a casting aluminum alloy production process, in particular to an environmental protection and energy-saving short-flow casting aluminum alloy production process. Background technique: [0002] The production process of the existing cast aluminum alloy ingots generally includes process steps such as compounding of aluminum alloy components, alloying, refining with refining agent, and slag removal in the furnace. The current production process of casting aluminum alloy ingots has problems such as high energy consumption, large heat loss, high casting loss, and low production efficiency. Taking the A356 cast aluminum alloy as an example, the production process is as follows: adding metal silicon into the high-position furnace and spreading it on the bottom of the furnace, heating up the furnace to preheat the metal silicon, and pouring high-temperature primary aluminum liquid into the furnace from a vacuum bag , and add titanium...

AI Technical Summary

Problems solved by technology

[0003] (1) The preheating of metal silicon and the baking in the furnace require a certain furnace temperature in the furnace, and the baking of metal silicon needs to continuously raise the temperature of the smelting furnace to maintain a constant temperature in the furnace, which increases production energy consumption

[0004] (2) After the molten aluminum in the vacuum bag is poured into the high-level furnace, the temperature drops to about 800°C. Compared with the raw aluminum liquid at 940°C that has just been pumped in, more than 100°C was wasted in the process of transportation and furnace reversal, and the heat loss is high;

[0005] (3) It takes a long time to melt silicon in the high-level furnace, with an average of more than 180 minutes per furnace. The temperature required for aluminum to completely dissolve metal silicon needs to reach above 700°C, and the temperature of the molten aluminum in the vacuum bag is poured into the high-level furnace. The temperature drops to about 800°C , in the process of melting silicon, the heat of the original aluminum liquid is still being lost, which cannot meet the temperature requirements in the long-term melting process of silicon, so it is necessary to heat the high-level furnace to maintain the reaction temperature, which further increases the production energy consumption;

However, in the aluminum ash produced by the existing chlorine salt refining agent after refining, because it contains the above-mentioned chlorine salt, if it is added into the electrolytic cell, chlorine elements, potassium elements, etc. will have adverse effects on the electrolytic molten salt system, such as eroding the carbon block, reducing the The life of the electrolytic cell, etc. Therefore, the aluminum ash produced after refining and purifying the aluminum alloy melt by adding a chloride salt refining agent cannot be recycled and reused by electrolysis because it contains a chloride salt compound, and a large amount of aluminum ash produced after refining accumulates and becomes dangerous. Waste, but also spend a lot of money to deal with aluminum ash; some chlorine salt refining agents will also produce harmful gases in the refining process, polluting the environment

[0007] (5) The vacuum bag conveys the raw aluminum liquid and the alloying of the molten silicon is carried out step by step, and the two process steps take a long time, resulting in a long time-consuming process of the entire casting production process and low production efficiency

[0008] (6) The homogenization of the solution components depends on the particle size of metal silicon. The grade of metal silicon used in the casting production of most aluminum alloy ingots is 441, and the particle size of metal silicon is 50-150mm, and the larger metal silicon particles are reduced. It takes about 120 minutes for the contact area with the molten aluminum to increase the reaction time, so that the silicon molecules can be evenly diffused into the molten aluminum body and alloyed. Because the melting time of silicon is long, the average time per furnace is about 180 minutes or more, and the production efficiency is low.

[0009] (7) The high-level furnace of the melting furnace is in the process of melting silicon and removing slag for a long time, resulting in 1.8% of the original casting loss

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