【摘要】 白水回用于废纸的碎浆,将使系统中含有较高的钙离子,在后续的过氧化氢漂白中易生成硅酸钙垢物。本研究在脱墨浆(钙离子含量为绝干浆的0.23%)中加入聚丙烯酸钠、二乙烯三胺五甲基膦酸(DTPMPA)和硫酸镁等硅酸钙阻垢剂,考察了它们对过氧化氢漂白效果的影响。结果表明,聚丙烯酸钠、DTPMPA和硫酸镁均能使漂白效果有一定的改善,特别是聚丙烯酸钠和DTPMPA能在较大的用量范围内(绝干浆的0-0.5%)使漂白效果持续改善,硫酸镁则在绝干浆用量的0.69%时达到最佳的漂白浆白度,继续增大硫酸镁用量使漂白效果下降。更多还原

【Abstract】 Using recirculated white water in repulping recycled paper will increase the content of calcium ion in the system to high degree,so that it is easy to form calcium silicate scaling in the subsequent hydrogen peroxide bleaching process.In this study,sodium polyacrylate dispersant,DTPMPA,magnesium sulfate wereadded as scaling inhibitors into a deinked pulp where the calcium content was as high as 0.23% on odp(oven-dried pulp),and their effects on peroxide bleaching were investigated.The results indicated that all the three inhibitors can enhance the bleaching effects to some extents,especially,for the polymeric dispersant and DTPMPA,the bleaching effects can be continuously enhanced in a large dosing range(0%-0.5% on oven dried pulp),but for the magnesium sulfate,maximum bleaching effect was achieved at the dosage of 0.69% on odp,as the dosage continued to increase,the bleaching effect would be decreased.更多还原