Abstract

Herein, an innovative method to improve the dewatering of micro- and nanofibrillated cellulose (MNFC) containing furnishes is proposed. This method is based on fiber flotation in which cationic bubbles are injected into the furnish to separate fibers from liquid medium and accumulate them on the surface of the furnish. These cationic bubbles are generated by pressurizing a solution of Hexadecyltrimethylammonium chloride in deionized water in a dissolved air flotation (DAF) tank. The drainage properties of the furnishes with MNFC content from 0% to 25% were studied. With the help of the cationic bubbles, drainage rate of 0% and 15% MNFC furnish increased from 183 ml/s to 210 ml/s and 38 ml/s to 113 ml/s, respectively. The final couch solids content of these furnishes also increased from 16 wt% to 23 wt% and from 21 wt% to 24 wt%, respectively. Cationic bubbles flocculate MNFC fibers and increase retention. Sheets characteristics including morphology, permeability, mass distribution and surface profilometry were investigated. Cationic bubbles help structure fiber elements and improve the sheet formation.

摘要

在此，提出了一种改进含有微纤化和纳米纤化纤维素 (MNFC) 的配料脱水的创新方法。该方法基于纤维浮选，其中将阳离子气泡注入配料中以将纤维从液体介质中分离出来并将它们聚集在配料表面上。这些阳离子气泡是通过在溶气浮选 (DAF) 罐中对去离子水中的十六烷基三甲基氯化铵溶液加压而产生的。研究了 MNFC 含量为 0% 至 25% 的家具的排水性能。在阳离子气泡的帮助下，0% 和 15% MNFC 配料的排水率分别从 183 ml/s 增加到 210 ml/s 和 38 ml/s 到 113 ml/s。这些配料的最终沙发固体含量也分别从 16 wt% 增加到 23 wt% 和从 21 wt% 增加到 24 wt%。阳离子气泡使 MNFC 纤维絮凝并增加保留。研究了包括形态、渗透性、质量分布和表面轮廓测量在内的片材特性。阳离子气泡有助于结构化纤维元素并改善片材的形成。