Process

Items

Traditional pretreatment process

Alkaline Degreasing Process

Complexity 

of 

production 

process

The process is 

complex which 

affects the 

production 

efficiency. 

The number of 

standard 

pretreatment 

process baths 

is 10.

The process 

can be reduced 

to five baths: 

weak acid 

rinsing→ rinsing

→alkaline 

degreasing→ 

rinsing -rinsing

→ oxidation

Acidic 

waste 

water 

amount

A large amount of 

acidic (fluoride-

containing) waste 

water is produced 

and the amount

of waste water

produced in the 

production of per 

ton aluminum 

profile is 5-8 

tons. It accounts 

for most of the

acidic waste water 

producedby the 

whole oxidation line.

No acidic waste 

water is 

produced,on the

contrary, about 

2-3 tons of

alkaline waste 

water are 

produced per 

ton of 

aluminum profiles 

treatment 

which can save 

largeamount of 

waste water 

treatment cost.

Aluminum 

loss

The loss of 

aluminum is 

large. The loss of 

aluminum is 

4-8 kg per ton of 

aluminum profile 

in production. 

According to the 

annual output of 

10,000 tons, 

the waste weight

of extruded 

profile is 40-80 

tons per year.

The loss of 

aluminum is 

less than one 

tenth of that of 

alkaline etching,

the average 

aluminum loss 

is about 

0.4 kg/ton. 

The annually 

saved cost of 

raw materials is 

very 

considerable.

Waste 

residue 

amount

A large amount of 

waste residue is 

produced,which 

increases the 

production cost. 

More than 70% of 

the oxidized 

waste is produced

by pretreatment.

The waste 

residue 

produced is 

less than one 

tenth of the 

traditional 

process. This 

can greatly 

reduces  waste 

residue

treatment cost.

Workshop 

environment

Alkaline etching 

bath will produce 

a lot of alkali fog 

when it works, it 

is not only 

deteriorates the 

working 

environment of 

the workers, 

but also destroys 

the workshop 

equipment, 

oxidation and 

electrophoresis 

process, and 

increases the 

management cost.

No alkali fog 

and alkali odor 

produced which 

achieves a 

friendly 

workshop 

environment.

Environmental 

Protection 

of 

Formula

F^- containing

F^- free