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在阳离子聚丙烯酰胺(CPAM)/膨润土絮聚体系中,研究了羧甲基纤维素(CMC)改性纤维对沉淀碳酸钙(PCC)沉积和脱水过程的影响。结果表明,在最初加入CPAM时,用10mg/g的CMC改性纤维会减少PCC的沉积量;当CPAM加入量为2mg/g时,PCC的沉积效果较好。研究还发现,在较低的CPAM加入量下,PCC在未经CMC改性纤维中的沉积率较高。膨润土的加入量(对经40mg/gCMC改性后的纤维)为0.5mg/g时,PCC的沉积率达到最大值继而稳定。这表明,高表面电荷和CMC在纤维表面的构象会导致CPAM和膨润土微粒之间的相互作用改变。脱水实验的结果表明,CMC改性会延长浆料的滤水时间,因为浆张变得更致密。高的CPAM和膨润土加入量可以抵消这些不利影响。此外,脱水作用也受到CMC和CPAM质量比的影响。本实验的研究没有在最佳CMC和CPAM质量比下进行,是在较低CPAM加入量下进行的。因此,纤维表面含有CMC时,化学品不恰当的质量比会引起浆料滤水时间的延长,因为在较高的CPAM加入量下没有观察到CMC对浆料滤水时间的影响。
In cationic polyacrylamide (CPAM) / bentonite flocculation system, the effect of CMC modified fiber on precipitation and dehydration of precipitated calcium carbonate (PCC) was studied. The results showed that when CPAM was first added, the amount of PCC deposited by CMC with 10mg / g CMC decreased. When CPAM was added at 2mg / g, the deposition of PCC was better. The study also found that at lower CPAM loadings, PCC deposited higher rates in CMC-modified fibers. When the amount of bentonite added (modified with 40mg / g CMC) was 0.5mg / g, the deposition rate of PCC reached a maximum and then stabilized. This shows that the conformation of high surface charges and CMC on the fiber surface can lead to a change in the interaction between CPAM and bentonite particles. The results of the dehydration experiments show that CMC modification prolongs the drainage time of the slurry because the slurry becomes denser. High levels of CPAM and bentonite can counteract these adverse effects. In addition, dehydration is also affected by the mass ratio of CMC to CPAM. The experimental study was not conducted at optimal CMC and CPAM mass ratios, and was performed at lower CPAM loadings. Therefore, an inappropriate mass ratio of chemicals to the fiber surface causes CMC to lengthen the slurry drainage time as no effect of CMC on slurry drainage time is observed at higher CPAM loadings.