Defoaming solutions for paper industry

Pulping process

1. Waste paper pulping (caustic soda, limestone, soda ash)

2. Alkaline pulping

3. Sulfite pulping

4. Sulfuric acid pulping

Papermaking auxiliaries include fluorescent brightener, resin control agent, filter aid, surface sizing agent, slurry sizing agent, Defoamer, dispersant, bactericide, wet strength agent, softener, pigment, etc

The sources of paper making foams:

1.The bubbles on the surface of the paper in tanks, tanks and boxes.

2.Small bubbles in the paper material and adsorbed on the fiber or dissolved in water

The harm of foam to the paper industry:

Foam reduces pulp washing efficiency

Fiber loss due to foam overflow

Paper is broken in the process of papermaking

Holes appear on the finished paper sheet

Three states of gas in paper:

A. Free  (tiny)

B. Combined (adsorbed)

C. Dissolved (fine)

Hazards of gas: affect the papermaking process and paper quality!

The effect of degassing:

1. Solve paper defects such as bubble point and pinholes on paper

2. Helps to improve the evenness

3. The quality of paper sheets is more stable

4. Improve the dehydration capacity of the forming part

Degassing methods: mechanical degassing, chemical degassing.

Papermaking water defoaming:

Foam in the papermaking wastewater can be treated with ordinary silicone defoamer.

https://www.nvchemical.com/product/Defoamer-For-Papaer-Industry.html