Over 400 tons of rolled shell plates successfully export to Laos. These shell plates are used in the manufacture of 8 digesters. The digester is 17 meters high and with a diameter of 5.8 meters and 10.5 meters. Each digester requires 14 shell plates, a total of 112 pieces, with a total weight of 400 tons.
The digester is a large tower container that needs to be assembled and welded at the construction site, and the digester is the main equipment for paper pulping.
Pulp digester or digester, is a large vessel for chemical pulping and dissolved fiber steaming section. As we all know, the raw materials of paper pulp like grasses, bamboo, wood and other sources are cooked in the digester. These raw materials react with a chemical liquid and get the paper pulp, which is mostly composed of cellulose. The paper pulp, can then be sent to washing bleaching system and applied to paper making processing. There are two types of digester in the chemical pulping productions, for the different pulping processing - vertical digester and horizontal digester. The vertical digester is used mostly for the super batch cooking. The most advanced batch-cooking technology -displacement cooking process is usually adopted, as it requires low cost and high-quality pulp is obtained. Different raw materials like 316L steel, carbon steel, stainless steel, duplex stainless steel, and composite plate are used in making of the digester series.
Paper pulp processing refers to the production activity of paper pulp by mechanical or chemical processing method. It can be generally divided into the following main steps:
Wood storage → Wood sawing → Debarking and Knotting→ Wood cutting for chips→Cooking→Washing→Screening and Purifying→Unbleached pulp (or→ Bleaching→Bleached pulp) →Soaking and Refining
Paper mill digester is used for the cooking process. The cooking process is an important step in the pulp processing process. It is a complex chemical process. It is to send the plant fiber raw material after the mechanical pretreatment into the digester with chemical cooking liquor under high temperature and pressure for further treatment. The lignin and other impurities will be dissolved and removed. Finally, the chemical pulp is obtained. The purpose of the cooking process is to remove the lignin in the fiber raw material, retain cellulose and hemicellulose and dissociate the fibers into the required pulp by using chemical agents according to the needs of different types of pulps.
Digester can be divided into batch type and continuous type:
Key steel fabrication services that we perform for pulp and paper making companies, OEMs and equipment manufacturing firms include plate bending, mechanical engineering, manufacturing of wear-resistant components, ASME pressure vessel fabrication, heat exchanger construction, plate rolling, plate forming, metal forming, cold forming, hot forming, steel plate fabrication, welding, heat treating, plate cutting, and plate straightening. We have the capabilities, industry experience and specialized equipment needed to form, cut, machine, process and join most types of heavy steel, alloy steel or metal.
Openex offers metal fabrication for pulp and paper mills that includes products, such as:
Contact us at sales3@openex.com.cn or call us at +86 186 5928 0806 for more information about fabrication for pulp and paper making and to receive a free project quote today.