氢氧化钠-硫脲-尿素体系中温预处理对玉米秸秆磨浆性能的影响

The effect on refining property of corn straw after the pre-treatment of NaOH-thiourea-urea system under medium temperature condition

为探究碱脲体系在中温条件下对木质纤维原料磨浆性能的影响,在本课题中利用氢氧化钠-硫脲-尿素体系处理玉米秸秆,在中温以及高纤维浓度(20%)的条件下,通过单因素试验探求其最佳预处理工艺。结果表明:在浸渍时间15min、用碱量6%、处理温度70℃、处理时间60min的条件下,该原料的磨浆性能可得到有效改善。与经氢氧化钠水溶液预处理后制得漂白化学机械浆相比,经氢氧化钠-硫脲-尿素体系预处理制得漂白化学机械浆细浆得率、白度、抗张指数和耐破指数分别提高2.28%、5.94%、18.8%和20.5%,磨浆能耗和松厚度分别降低16.1%和4.65%。此外两种漂白浆纤维中元素含量差别不大。

In order to study the effect on the refining property of lingo-cellulose fibers with the treatment of NaOH-urea system at medium temperature,the NaOH-thiourea-urea system was used to treat corn straw and the optimal treating conditions were determined through the single factor tests under medium temperature and high fiber concentration(20%).The results showed that the optimal conditions are chosen as the soaking time of 15min,alkali charge of 6%,treating temperature of 70℃and treating time of 60min.Compared with those of the bleached chemi-mechanical pulp of corn straw prepared by NaOH aqueous solution,the accept yield,whiteness,tensile index and burst index of the bleached pulp prepared by NaOH-thiourea-urea system were increased by 2.28%,5.94%,18.8%and 20.5%respectively,and the refining energy and bulkiness are decreased by 16.1%and 4.65%respectively.Besides,there were no remarkable variations on the organic element contents.