Aluminum alloy fluoride-free ammonium-free four-in-one sand surface pretreatment process

Abstract

An aluminum alloy fluoride-free ammonium-free four-in-one sand surface pretreatment process comprises a reagent recovery system and a reverse in-series water-saving system; wherein the reagent recovery system comprises a four-in-one tank and a non-flowing water-washing tank subsystem, the non-flowing water-washing tank subsystem is arranged in an integral and reverse in-series connection manner, afirst water supplementing port is formed in the initial end of the water flowing direction, and a water outlet of the terminal is connected with the four-in-one tank in in-series; the reverse in-series water-saving system comprises a function tank subsystem and a flowing water-washing tank subsystem arranged between function tanks. The function tanks are respectively arranged between flowing water-washing tanks, the upstream function tanks of the function tank subsystem are compatible with the downstream function tanks of the function tank subsystem along the flowing direction of washing water, and the flowing water-washing tank subsystem is arranged in an integral and reverse in-series connection manner. Through the aluminum alloy fluoride-free ammonium-free four-in-one sand surface pretreatment process, fluorine and ammonium pollution of aluminum alloy anodic oxidation pretreatment can be effectively solved, water of an anode oxidation line is greatly saved, the pollution control amount of an enterprise is greatly reduced, the production cost is reduced, and the effect is improved.

Description

technical field [0001] The invention relates to the technical field of surface treatment of aluminum materials, in particular to a fluorine-free and ammonium-free four-in-one sand front treatment process for aluminum alloys. Background technique [0002] Aluminum alloy sand surface treatment processes are mainly divided into three categories: alkali etching, acid etching and mechanical sandblasting. [0003] The traditional alkaline etching process of aluminum profiles has been used for more than 100 years. Alkali etching has the disadvantages of high aluminum consumption, high alkali consumption, more alkali slag, difficult process control, many defects, high production cost, COD content, and large environmental pollution, which has long been recognized by the industry. Standard alkali etching slot arrangement figure 2 As shown, 1# oil removal tank, 4# alkali corrosion tank, 7# neutralization tank, 11# oxidation tank and 14# sealing tank are working tanks, and each workin...

AI Technical Summary

Problems solved by technology

[0023] 1. The process is more complicated and the slots are more

There are a total of 13 slots in front of the oxidation tank, 4 working tanks, and 9 washing tanks, which are more complicated;

[0024] 2. The efficacy is too low

The time is too long, which seriously restricts the production capacity of the oxidation line;

[0025] 3. There are too many working tanks, and the consumption of chemicals is too large

In addition to the cost of water, the treatment and discharge of these wastewater containing fluorine, ammonia nitrogen and COD will cost extra;

[0027] 5. The fluoride ion content of 1# tank is 5-10g / L, and the fluoride ion content of 4# tank is 30-50g / L. The HF gas released during production endangers the health of workers, corrodes equipment and pollutes the atmosphere

Wastewater contains high concentration of fluoride ions, which need to be specially treated, and the waste water cannot be reused;

[0028] 6. Tanks 1#, 4# and 10# contain ammonia nitrogen, and 7# contains COD, making wastewater treatment even worse

These fluorides are now strictly banned

[0041] 2. Chromium-containing anhydride: 7# tank contains CrO 3 35g / l, it is not allowed to use like this

[0071] (2) Na surface agent 3 PO 4 Improper selection, insufficient sanding ability

[0073] (4) Sodium dodecyl sulfonate is improperly selected, and the liquid level rises too fast

[0074] 2. The slag extraction system is too complicated, and the production line workers are not suitable for complex operations

However, in actual production, due to the insufficient capacity of the complexing agent in the 1# four-in-one tank, the chemicals brought out decompose too quickly in the 2#, 3#, 4#, and 5# tanks, and the walls of each tank are fouled. When cleaning the bottom very troublesome

[0076] 4. The water circulation purification treatment system has a good idea and online purification, but the production line workers are not suitable for complex operations

For the traditional alkali etching, acid etching and sandblasting process complex, too many working tanks and washing tanks, low work efficiency, large amount of chemicals, large waste water discharge, high cost of treating fluorine, COD and ammonia nitrogen, and low sandblasting efficiency, The disadvantages of high scrap rate, taking into account the advantages and disadvantages of the Chinese patent 200510101420. The aluminum alloy sand surface treatment process of saving medicine and water also plays the most fundamental purpose: saving medicine and water

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