The Different Designs of Two-stage Oxygen Delignification of Kraft Pulp

The impact of temperature on the delignification rate is higher than on the cellulose degradation rate at the initial stage of oxygen delignification, and there is little difference of the impacts on the delignification rate and cellulose degradation rate at the end of oxygen delignification process. The influence of oxygen process on delignification rate is lower than cellulose degradation rate at the initial stage of oxygen delignification, there is little difference of the influences on both delignification and cellulose degradation rates. The impacts of OH- concentration on the delignification rate and cellulose degradation rate are similar, however, its impact on cellulose degradation rate is higher at the end of delignification process. Base on this, three different designs of delignification process are analyzed and compared. The factors which impact the oxygen delignification efficiency are not only limited to these in the actual production. The pulp carried over to oxygen delignification stage is also very important.