It is not so easy to use water in the papermaking process.

Whether the quality of water is good or not has a certain influence on the quality of pulp and paper. Capacitor paper, electrical insulating paper, photo paper and rayon pulp need to be higher than the general production water requirements.

In particular, capacitor paper and electrical insulating paper are produced by using cation and anion exchange resin treated water.

For boiler water, the required quality is higher. Because hard water can foul the boiler and affect heat transfer. Oxygen, carbon dioxide and chloride ions in the water have an erosive effect on the boiler wall. These impurities are slightly higher in content and are detrimental to the operation of the boiler.

Therefore, the boiler water must be softened, deaerated and desalted to meet the boiler water standards.

The high content of impurities in the water has a certain influence on the quality of pulp and paper. For example, the high suspended matter content can reduce the whiteness and strength of the paper, in addition to increasing the dust of the paper.

Excessive hardness in water is detrimental to paper sizing. The main reason is that when the calcium and magnesium salts are too high, these salts will interact with some of the rubber compounds, resulting in loss of the rubber compound.

In addition, the alkaline pulp is washed with hard water, and the calcium, magnesium ions and the dissolved resin in the black liquor react to form an insoluble calcium soap or magnesium soap, which is adsorbed or deposited on the fiber, which causes difficulty in bleaching, and more serious causes Resin barrier.

The water contains iron, manganese and other metal ions, which will be adsorbed on the fibers during the pulping and papermaking process, causing discoloration of the paper or pulp. Therefore, it is generally used to make high-grade paper, and the iron content in the water is not more than 0.1-0.2 mg/liter.

If it is like a base paper, if it contains a high amount of iron, it will cause yellow rust on the paper, which will seriously affect the use requirements. If the chlorine ion content in the water is too high, some high-grade paper or neutral wrapping paper and rust-proof base paper may be produced, which may cause corrosion of the packaged metal products.

Organic matter is often present in water in a colloidal or dissolved state. This is caused by decaying organic matter such as algae that are contaminated by water sources and grown in water. It makes the water color, turbid, and even odorous, so when used in pulp and paper, the fiber strongly adsorbs organic pigments or gums. Treatment with alum will precipitate these materials on the pulp, thereby reducing the whiteness of the pulp or affecting the bleaching process.