Controlling corrosion in process water systems

DETAILED DESCRIPTION The preparation of formaldehyde-free binder coated glass fiber products requires that the binder composition have a pH of less than about 3.
5 to effectively coat the glass fibers and for proper curing.
This is generally accomplished by the addition of acid during the process of making the binder composition.
As a result, the process water and wash extracted during the coating step has a very low pH.
Due to the low pH, the process water is very corrosive and causes significant wear on the piping and storage equipment used to handle the recycled process water.
This corrosion can be avoided by neutralizing the process water after it is extracted from the product such that the water has a pH of from about 6.
0 to about 8.
0.
The water should also be treated to counteract any corrosion-causing agents present.
Raising the pH of the extracted process water essentially involves adding a base or other neutralizing composition to the process water after it is extracted from the glass fiber product.
In a preferred embodiment, the pH of the process water after extraction is determined.
If the pH of the process water is less than about 6.
0, then a neutralizing agent is added to the process water to increase the pH to greater than about 6.
0, preferably about 7.
0 or more.
Neutralizing agents useful in the practice of the invention include those who can increase the pH to about 7.
0 still provide corrosion inhibition.
Some of the neutralizing agents useful in the practice of the invention are lime, ammonia, and potassium hydroxide with lime preferred.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood.
Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.
It should be appreciated that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention