COMPARING THE FLOCCULATION BEHAVIOR OF WET-END RETENTION SYSTEMS USING FOCUSED BEAM REFLECTANCE MEASUREMENT
Flocculation optimization on a machine often begins with the monitoring of consistency, retention, and charge. Obviously, a flocculation sensor to directly control flocculation would considerably improve the control process. In this paper, FBRM（Focused Beam Reflectance Measurement）was used as the tool to study the process of flocculation induced by various retention systems and the effects of types and characteristics of additives on flocs properties were researched. FBRM could realize the accurate evaluation of the flocculation of suspension quantitatively. It provided a real-time, in-line measurement, and the parameters including mean chord length (MCL), total number of counts and chord distribution. The application of FBRM was beneficial to understand the flocculation phenomena of wet-end of papermaking overall. The flocculation process of PCC (Precipitated Calcium Carbonate) suspension was studied. The results showed that the extent of flocculation varied broadly from one retention aid system to another. MCL of flocs induced by PAC (Polyaluminum Chloride) were the least and the optimum flocculation was achieved at zero Zeta potential. The flocs induced by PDADMAC (Polydiallyldimethylammonium Chloride) and CPAM (Cationic Polyacrylamide) were bigger; especially the latter, and the optimum flocculation of them took place at negative Zeta potential. Dual polymer system formed larger flocs than single-component CPAM system. The dosage of PAC had great effect on flocculation of PAC/APAM (Anionic Polyacrylamide) system, and the lack of PAC could not be compensated with increasing the dosage of APAM. The size of flocs induced by CPAM/bentonite system was affected by dosage of CPAM obviously, rather than by dosage of bentonite.
flocculation flocs retention systems FBRM MCL
Hu Fang Hu Huiren
Qiqihar University, Qiqihar, 161006, China State Key Laboratory of Pulp and Paper Engineering, South Tianjin University of Science & Technology, Tianjin,300457, China
国际会议
广州
英文
1601-1604
2010-11-08（万方平台首次上网日期，不代表论文的发表时间）