Research on Kraft pulping Delignification of bamboo (Neosinocalamus)

Bamboo, as a kind of non-wood raw material, has a long, thin fiber with wide distribution and rich abundance in China. Its pulping properties are between softwood and hardwood. Adapting to the Chinese situation, developing bamboo pulp industrialization, according to the local conditions, is an available way to solve the shortage of fiber material for paper-making. Delignification of bamboo (Neosinocalamus) was carried out by conventional kraft and soda pulping under varying conditions to determine the relationships between selected cooking parameters (EA 14 similar to 20%, sulfidity 0 similar to 40%, maximum temperature 160 and 165 degrees C, and time at maximum temperature 60 similar to 110 min) and pulp properties (kappa number and yield). Results indicated that in order to obtain relatively low kappa numbers(17 similar to 27), high sulfidity(20 similar to 40%) at lower EA(14 similar to 16%) increased pulp yield compared to the case of low sultidity(0-10%) at higher EA(16 similar to 18%). Pulp with lower kappa numbers (13 similar to 15) and acceptable yield can be obtained at a sulfidity level of 20 similar to 30% with 18% EA or at a sulfidity level of 10 similar to 30% with 20% EA. Meanwhile, bamboo pulp in this condition not only helps to decrease kappa number in the subsequent oxygen delignification process, but also reduces the cost of chemicals in the bleaching process.