Fans for ClO2

Paper is a material made ​​from cellulose fibers that are obtained by chemical and mechanical processes .

The main source of the cellulose is wood. Its chemical composition is highly variable and is composed primarily of cellulose, lignin , hemicellulose, and 5% to 10% of other materials. The lignin polymer is the responsible of the typical brown color of pulp paper.

Depending on the chosen final product pulp follows different manufacturing processes. In the case of white paper a bleaching process in required to remove off the hemicellulose and the lignine , producing minimal physical damage to the cellulose fiber.

Bleaching methods used are the ECF (Elemental Chlorine free ) and TCF (Totally Chlorine Free).

One of the most important changes in the process of pulp bleaching was the substitution of Cl₂ with ClO₂, chlorine dioxide . Such change was essential in reducing the amount and type of organochlorines formed and produced and the disappearance of dioxins and tetrachloride furans in the effluents.

Industrial production of chlorine dioxide is generally based on processes to reduce the NaCl in NaClO₃ in H₂SO₄ solutions. However, to minimize risks of transport and for being chemically stable , is produced on site.

The chlorine dioxide gas is transported to an absorption tower where it is dissolved in cold water to produce the bleach solution of aqueous chlorine dioxide .

As chlorine dioxide is an element highly toxic and corrosive, facilities must have safety systems designed specially for the operation and to avoid risk of exposure to this fluid in case of leakage.

Also the choice of materials is critical to ensure the life of the equipment.

Tecnium supplies centrifugal fans for handling chlorine dioxide being our clients from companies providing installations to the end user’s paper mills.

The fans are available in materials specially adapted to process conditions and with sealing systems to prevent leakage of polluted gases into the atmosphere.