Papermaking Water Treatment – Improve Process Water Quality

The papermaking industry puts strict requirements on water quality in its production and processing processes. The turbidity and color of water directly affect the production and bleaching effect of paper, while excessive iron and manganese ions in water can result in white paper becoming yellow easily. Additionally, water alkalinity reflects its pH value, which in turn affects the optimal pulp ratio during papermaking. Therefore, maintaining good water quality is crucial throughout the entire production process.

The papermaking industry is a highly wastewater-intensive industry. For many paper mills, wastewater treatment is a challenging issue. During the production, the pulping and papermaking processes generate a significant amount of wastewater containing harmful substances such as lignin, hemicellulose, sugars, residual alkali, inorganic salts, volatile acids, and organic chlorides. This wastewater features large discharge volume, high chemical oxygen demand (COD), significant pH variations, high coloration, and sulfide-like foul smells, making it difficult to deal with industrial wastewater. If directly discharged into the environment, it will cause severe pollution. Therefore, the papermaking industry should adopt water treatment processes to purify wastewater, meet discharge standards, or achieve water reuse.