Pulp cooking is the main process of paper and pulp making. The plant fiber materials pass through the pre-treatment of cutting, screening, dedusting, and the materials are send into pulp digester with chemicals, then the lignin and other impurities are removed and paper pulp obtained.
Pulp cooking is the process of delignification. To be specific, the pulp cooking process uses the chemicals to remove the lignin from the fiber materials according to the need of different paper pulp, keep the cellulose and hemicellulose, and dissociate the fibers into pulp. The pulp cooking process can be simply summed into four steps, charging of materials and liquor, heating, heat preservation and blowing.
As for the pulp cooking equipment, pulp digester and blow tank are two main equipment of pulp cooking. By different pulp cooking processes, there are various types of pulp digester applied in the paper pulp making. The batching cooking digester has two types: rotary digester and vertical digester. The continuous digester includes continuous tubular digester, M & D digester and vertical digester.