The possibilities of utilizing porous sodiumaluminosilicate as wet end filler and also as a white water clarifier by dissolved air flotatioin were studied. Micro flocs generated by highly porous sodiumaluminosilicate replacing magnesium siticate in teh wet end gave betterretention and minimized suspended solids in white water. It was found that interfaction betwee nporous sodiumaluminosilicate and negatively charged suspended or colloidal matters or other anionic by-products possibly derived from peroxide bleached pulp, resulted in agglomerates that could be particlly removed by flotation. A partial elimination of anionic trash from white water also helped to improve first pass filler retention .It has been found that retention and drainage are inherently associated with white water consistency. most importantly fiber and fileler characterisics. Porous sodiumaluminosilicate was found to be effective under mild alkaline condition. Morphological analysis of floc-structure revealed that both size and size distrbutions are more uniform for porous fillers. Higher price of high brightnes sodium silicate compared to a relatively less bright filler such as magnessium silicate is expected to be ocmpensated by improved retention .brightness and opacity. Improved white water quality is another advantage of prous sodiumaluminosilicate.
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