Chlorination as a traditional bleaching technology, the waste water discharged from the bleaching process contains pollutants such as dioxins, and organic chlorides are difficult to degrade and seriously pollute the environment.
Ozone technology is used in the paper industry for pulp bleaching and decolorization, wastewater decolorization, and advanced wastewater treatment. Ozone has become the preferred solution in the paper industry due to its low cost, environmental pollution and wide use.
1. Ozone pulp bleaching
Ozone is a highly oxidizing bleaching agent. In the pulp bleaching system, ozone reacts with pulp lignin through oxidation, which causes the chromophore to lose its “coloring” ability and achieve bleaching. In addition to removing colored substances, it further removes residual lignin and other impurities, improves the whiteness and purity of the pulp, and makes the whiteness last.
Advantages of ozone bleaching:
1. Ozone bleaching is a chlorine-free process and has no pollution to the environment;
2. Ozone is a strong oxidant, with strong reactivity and high efficiency;
3. Replace chlorine in the pulp bleaching process to reduce chloride emissions;
4. Ozone oxidation reaction is rapid, reducing the cost of bleaching;
5, ozone oxidation bleaching ability, improve the whiteness of paper and reduce the yellowing of pulp.
Ozone pulp wastewater treatment
Ozone is a strong oxidant used in the pretreatment and advanced treatment of industrial wastewater. It has many functions in water treatment: sterilization, decolorization and oxidative decomposition. Ozone is mainly used for decolorization in wastewater treatment. Degrade organic matter and reduce COD and BOD values.
Ozone strong oxidizing effect can decompose organic matter of macromolecule into smaller organic matter, change the toxicity of pollutants, and biochemically degrade. At the same time of degrading organic matter, COD and BOD deserve to be reduced to further improve water quality.
In dealing with the problem of large chromaticity of wastewater, ozone oxidation can cause the color of the dye to assist the color or the bivalent bond of the chromogenic gene to be broken, and at the same time destroy the cyclic compound constituting the chromophore group, thereby decolorizing the wastewater.
Compared with the traditional chlorine process, ozone has obvious advantages in the paper industry. It has strong oxidizing property, high speed and no pollution to the environment. It can not only reduce the pulp bleaching cost, but also reduce pollution emissions. Nowadays, environmental protection is more and more importance, ozone technology has plays a major role.
Post time: Sep-07-2019