马尾松SGW高白度全无氯漂白研究

Study on H_2O_2 High-Brightness-Bleaching of SGW from Masson Pine

对马尾松磨石磨木浆(SGW)进行了单段H2O2漂白和2段H2O2漂白试验,研究了不同预处理方法和条件对H2O2漂白效果的影响,提出了最佳的预处理工艺;同时还研究了以EDTA和MgSO4作为金属螯合剂改善H2O2漂白效果,进而确定了H2O2漂白的最佳工艺参数.结果表明,应用EDTA和MgSO4作为金属螯合剂,SGW经预处理后,采用两段H2O2漂白,漂后纸浆白度可由原浆的47.8%提高到74.5%,从而使制得的漂白浆能满足低定量高白度胶印新闻纸和其他高级纸种的生产要求.结果还表明,与传统CEH3段漂白相比,漂白废水中的CODCr减少78 5%,BOD5减少97%,且不再含有可吸附的有机卤化物(AOX).

This paper investigated the one-stage and two-stage H_2O_2 bleaching of stone ground wood(SGW) from Masson Pine, researched for the ways of improving H_2O_2 efficiency in the SGW bleaching, discussed the effect of the sequestrants on the removal of metallic ions, and studied several parameters in the H_2O_2 bleaching process. The results show that the H_2O_2 bleaching efficiency is improved obviously with the use of sequestrants and pretreatment prior to bleaching, and a brightness of 74.5% (SBD) can be achieved by the two-stage H_2O_2 bleaching after pretreatment under the optimum conditions. The results also show that the COD_(Cr) load in the H_2O_2 bleaching wastewater decreases by 78.5%, and the BOD_5 load decreases by 97% without containing AOX, compared with the traditional CEH bleaching.