What are the benefits of using silica sol in the paper industry?

2022-12-05 17:06 Mike

Due to the rapid development of papermaking technology, the rapid growth of large-scale highspeed papermaking machines in China, the continuous application of sandwich forming technology, the increase in the proportion of secondary fibers and fillers, and the increase in the degree of white water closure, higher requirements have been put forward Improved oneway retention of meshes, filtering. In order to solve the simultaneous problems of paper retention, water filtration and paper quality, the only way is to use a micro particle retention system. The system composed of cationic starch, cationic polyacrylamide and silica sol, as a new type of highefficiency particle retention system, shows very good competitiveness in improving retention rate and uniformity.


The particle retention mechanism is very complicated, which can be roughly explained as: adding cationic starch with high positive charge density and medium molecular weight to theslurry, forming fine fibers and fillers through adsorption, neutralization and flocculation


First enter the initial charge node of the floc, then add polyacrylamide with polymer mass and low charge density, and form large and loose flocs through bridging. These large flocs are broken into small cationic flocs under the action of high shear force such as slurry pump or pressure screen. Adding strong negative nanosilica sol with high specific surface area can effectively capture these small cationic flocs. These silica gel particles penetrate into the flocs, squeeze out the water in the flocs, and reform the net shape, uniform, small and strong flocs, firmly fixed on the fibers, and effectively stay on the net, so as to achieve the best lingering effect.


Advantages of silica sol particle retention system: (1) high retention rate and low production cost; (2) reduced white water concentration, which improves the stability of paper machine operation; (3) improves water filtration, increases speed, and increases output; (4) ) can greatly reduce the resin barrier property in the production process.


The silica sol particle retention system is more effective than the binary retention system, it can greatly improve the retention of fibers and fine materials, save costs, reduce costs, improve the stability of paper machine operation, reduce resin barriers, and improve the physicalindicators and appearance quality of paper.