In recent years, the world's new technology and equipment are: cooking technology and equipment
At present, the more advanced cooking technology and equipment in the world are Norway's improved continuous digester and isothermal digester. They are characterized by low kappa number (up to 25) after cooking, but do not reduce the pulp strength. In batch cooking, cold spray technology is more prominent. It is characterized by less energy consumption, higher pulp yield and higher cooking capacity than traditional methods.
From the perspective of development, deep cooking technology will be developed and applied on the basis of expanding and improving kraft cooking to reduce kappa number, energy consumption and pollution. Sulfur free pulping will also be a direction of future development. Bleaching technology and equipment
In recent years, the new technology used in the world is the element free chlorine bleaching technology (ECF technology for short), and the complete chlorine free bleaching technology (TCF technology for short) has been gradually applied. Compared with traditional bleaching methods, the two bleaching methods have the least advantage of greatly reducing environmental pollution. In traditional chlorine bleaching, the AOX content in wastewater is 2.4kg/t pulp, while in ECF and TCF, the AOX content in wastewater is 0.6kg/t pulp and 0.2kg/t pulp respectively.
In addition, using ozone, hydrogen peroxide and biological enzyme as bleaching agents to treat pulp will be the development direction of bleaching technology in the future. Papermaking technology and equipment
At present, the advanced methods used in the world are full flow hydraulic headbox with pinch net former and pressure sizing round net former, etc. the principle of fluid mechanics is used to disperse fibers, the principle of double-sided dehydration is used to solve the problems of high-speed forming and two-sided difference of paper, and multi-layer forming arrangement is used to produce high-quality paper. In terms of press, in order to improve the efficiency of dehydration, the difference between two sides, curliness and surface strength of paper, the commonly used new technologies are high-speed press, double-sided press, new transfer press, compound press and wide press zone press. The new paper machine and paperboard machine all adopt fully enclosed steam hood, dry net and bag type ventilation device; the high-grade paper machine adopts air cushion drying and other new methods. Coating technology and equipment
The development of coating technology includes the development of new coatings, coating preparation technology and equipment. Coater tends to adapt to high-speed production, coating compact and wide range of multi-functional form. At present, the emerging form of dryer is concerned by the industry due to its high thermal efficiency. The smallest new coaters are twin HSM roll coater and ABC coater from Sweden. It is characterized by easy adjustment of coating amount and wide range of coating amount.
