Study And Development Of The Industrial Tester Of Non-chlorine Bleaching

The problem of environment pollution for paper making would last for years. There were lots of organic chloride in the waste water of CEH bleaching, and the water system was badly polluted. So non-chlorine bleaching was got much attention in the years. There were many advantages which used oxygen in the bleaching process, such as saved the chemical medicine and energy consumption in bleaching process, decreased water pollution, recovered the waster water directly, and the bleached pulp had high clean degree, great brightness stability, good freeness and so on. It also decreased the waste charge in the bleaching factory and reduced the operation expense that used the oxygen delignification system. The green bleaching flow of non- chlorine was studied in the paper.According to the process of technics development and the selective principle of technics course, the equipment and result of oxygen delignification experiment in the lab was summarized, The amplificatory effect from mini-experiment to medium-test was reviewed. On the basis of lab experiment, the bleaching equipment-column bubble that used in medium-test was studied and designed, the control mode of every technologic parameter that affected oxygen delignification in the medium-test was designed. at last, the technical flow of oxygen delignification- series-wound column bubbles device was designed. In the end of the paper, the feasibility of the device was tested which used wheat straw chemical pulp.The result of oxygen delignification experiment of wheat straw pulp were as follows: 5% of pulp concentration, NaOH charge 3%, MgSO₄ charge 0.5%, about 80℃, 0.5MPa and reacting for 60min. The bleached pulp's brightness increment in the column bubbles was 8.6%, 8.2%, 7.6%, 5.8%SBD respectively. The oxygen cumulation was6.02Kg. The experiment achieved expectant result. The series-wound column bubbles device was not only feasible in technics, but also achieved the intention of energy conservation and discharge reduction of paper industry. The paper provided powerful basis for industrialization of non-wood pulp oxygen bleaching.