Corrosion inhibitor for aluminum corrosion control

Abstract

The invention discloses a corrosion inhibitor for aluminum corrosion control. In the molten aluminum continuous casting process, if drained water of a reclaimed water treatment station of an aluminum manufacturer is adopted as continuous casting aluminum ingot direct cooling water, grey spots are very likely to be caused on the surface of an aluminum ingot due to the problem of water quality, and the smoothness of aluminum is influenced. The corrosion inhibitor is prepared from, by mass percent, 1.5%-2.5% of benzotriazole, 4.5%-7.5% of isopropanol, 10%-15% of 2-phosphonobutane-1,2,4-tricarboxylic acid, 6%-8% of nitrilotrimethylene triphosphonic acid, 8%-10% of zinc sulfate heptahydrate and 57%-70% of water. By means of the chemicals, the appearance of the aluminum ingot can be guaranteed even though the drained water of the reclaimed water treatment station of the aluminum manufacturer is adopted as the aluminum ingot direct cooling water; the problem about an outlet of the drained water of the reclaimed water treatment station of the aluminum manufacturer is solved, and fresh water resources of enterprises are saved; and meanwhile the use cost of the chemicals is low, and the corrosion inhibitor has social, environmental and economic benefits.

Description

technical field [0001] The invention relates to corrosion control in the direct cooling process of molten aluminum water in an aluminum smelting enterprise, in particular to a corrosion inhibitor used for aluminum corrosion control, which is used for controlling the cooling corrosion process of molten aluminum water when the cooling water quality is relatively poor. Background technique [0002] Industrial extraction of aluminum is based on bauxite (Al 2 o 3 .xH 2 O) ore is used as raw material, which is dissolved in alkali under pressure to obtain sodium tetrahydroxyaluminate (Na[Al(OH) 4 ]), after precipitation and filtration, CO was introduced into the solution 2 Form aluminum hydroxide Al(OH) 3 Precipitate, filter and dry the precipitate, burn to get Al 2 o 3 , then the AL 2 o 3 and cryolite Na 3 AlF 6 The molten liquid is electrolyzed at a high temperature of about 1300K, and molten metal aluminum is obtained on the cathode, and the purity can reach 99%. The e...

AI Technical Summary

Problems solved by technology

When the aluminum ingot reaches the top of the casting machine, it has completely solidified into an aluminum ingot. At this time, the casting mold is turned over, and the aluminum ingot is released from the mold and falls into the cooling tank. Many enterprises use water to directly cool the aluminum ingot, and the quality of the water will be greatly reduced. To a certain extent, it affects the appearance of aluminum ingots. If groundwater is used to cool aluminum ingots, an electrolytic aluminum plant with an annual output of hundreds of thousands of tons may use millions of tons of groundwater all year round. It is easy to cause land subsidence due to overexploitation of groundwater, which is serious cause land subsidence

In coastal areas, it will also cause damage to the pressure balance between groundwater and seawater, causing seawater intrusion, resulting in the scrapping of motorized wells, difficulty in drinking water for humans and animals, soil salinization, and deterioration of groundwater quality.

If surface water is used as cooling water for continuous casting of aluminum ingots, the surface water quality cannot be controlled, especially if there are industrial sewage discharge enterprises along the river, it is easy to cause gray spots on the surface of aluminum due to the deterioration of cooling water quality, and aluminum production enterprises have to reinstall Re-casting greatly reduces casting efficiency. If gray spots appear on a large scale, other sections of the company have to reduce or stop production due to the poor operation of the casting process. It is difficult to guarantee the continuity of production

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