| Summary: | 碩士 === 國立屏東科技大學 === 森林系 === 92 === The purpose of retention aid system is to utilize chemicals to affix suspended and dissolved substances in white water onto the paper web, thus not only improve paper properties but also help machine runability. The system is an effective measure for economic operation. As environmental regulations are getting more stringent, this system could be an important step in lessening the organic and inorganic environmental impacts. Vast quantity of wastepaper usage, increase in filler content, changing papermaking system from acidic to neutral and alkaline, the high shear force encountered in high speed paper machine, and closure of white water system all dictate changer in retention aid system to cope with the critical retention and drainage problem.
This research is to utilize anionic polyacrylamide（A-PAM） and colloidal silica in order to retention aid. In the laboratory, utilize Dynamic Drainage Jar（DDJ）imitate the wet end system of the paper machine with different composition furnish. Analyses overall, its PCD and pH influence is indistinctive. The retention of fines average increases 16.28 %, first pass retention average increase 5 %, the retention of ash average increases 14.26 % and Improve drainage rate by 16.84 % equally. It is highest increment rate with anionic PAM of 200 ppm and colloidal silica of 4000 ppm overall.
In addition, the retention system of paper machine adds the colloidal silica to test. Its result increases by 1.7~6 % to first pass retention, the retention of ash increase obviously 2~4 %, lower 0.15 % of consistency of headbox, and consistency of white water is lower 0.05~0.085 % too. The other chemical additives consumption reduce, there is better controlling.
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