Method for removing iron through external circulation standing and cooling during continuous hot-dipping of zinc and aluminum

Abstract

The invention discloses a method for removing iron through external circulation standing and cooling during continuous hot-dipping of zinc and aluminum and relates to the technical field of hot-dip galvanizing. The adopted technical scheme is that: a low-temperature standing zinc pot is arranged on the side of a galvanizing zinc pot, zinc-aluminum melt is driven to pass through a pipe to be led out of the galvanizing zinc pot, so that zinc liquid flows into the low-temperature standing zinc pot, and the process of removing the iron in the zinc liquid is performed in the low-temperature standing zinc pot. The low-temperature standing zinc pot is heated by a resistor, and the temperature difference between the low-temperature standing zinc pot and the galvanizing zinc pot is reasonably controlled, the iron in the zinc-aluminum melt is separated out in the low-temperature standing zinc pot through standing and cooling by using different solubility of iron at different temperatures and density difference between iron-containing cadmia and the zinc-aluminum melt, and the iron-containing cadmia is generated and settled at the bottom of the zinc-aluminum melt; and the zinc-aluminum melt which is subjected to standing and purification passes through a pipe connected with the galvanizing zinc pot to flow back into the galvanizing zinc pot so as to finish the process for removing the iron from the zinc-aluminum melt. The method can be used in and out of the line of hot-dipping of zinc and aluminum, so that the content of the iron in the zinc liquid in the galvanizing zinc pot can be reduced obviously, the quality of coating is improved and the waste of the zinc and aluminum is reduced.

Description

technical field [0001] The invention relates to the technical field of hot-dip galvanizing, in particular to a method for continuous hot-dip galvanized aluminum in extracorporeal circulation and static cooling to remove iron. technical background [0002] Hot-dip galvanizing is a more effective and convenient steel anti-corrosion method. Its coating has excellent sacrificial anti-corrosion effect; hot-dip galvanizing layer is dense and durable. The zinc-aluminum alloy coating is widely used because it has both the durable protection characteristics of aluminum and the cathodic protection characteristics of zinc, the performance of the coating is superior to that of a single element coating, and the anti-corrosion performance is several times higher than that of pure zinc coating. Due to the excellent comprehensive performance and beautiful appearance of galvanized aluminum sheets, such as Galvalume coated steel sheets, there has been a trend in foreign countries to replace a...

AI Technical Summary

Problems solved by technology

At present, many typical galvanized aluminum Galvalume production lines have zinc dross problems that plague people. For example, Bluescope Steel in Australia has three Galvalume production lines that have serious zinc dross problems, and many domestic Galvalume production lines also have zinc dross problems.

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