化学热磨机械浆连二亚硫酸钠第二段漂白技术研究

Research on CTMP bleaching with sodium hydrosulfite as the second stage

经过氧化氢(P)漂白后的杉木CTMP浆再用连二亚硫酸钠(Y)进行第二段漂白,可有效地提高纸浆白度。本文对第二段(Y)漂白工艺进行了实验室研究。主要漂白工艺条件:连二亚硫酸钠1%～2%;焦亚硫酸钠(SPS)0.25%;添加剂STPP0.25%;漂白时间60min;漂白浓度2%～8%;漂白终点pH5.5～6;温度65～75℃。该漂白工艺已进行中试,并投入生产运行。

Chinese fir after hydrogen peroxide bleaching and bleached with hydrosulphite as the second stage, the pulp brightness can beeffectively improved. The paper performs a laboratory research on the second stage bleaching technology. The main bleaching technologicalconditions are: hydrosulphite 1%～2%, sodium pyrosulfite 0.25%, additive STPP 0.25%, bleaching time 60 min, bleaching concentration2%～8%, bleaching terminal point pH 5.5～6, temperature 65～75℃. The bleaching technology has passed the pilot experiment and has beenput into production run.