| 英文摘要 |
This study was in response to the incentive program of the Environmental Protection Administration, Executive Yuan encouraging waste recycling treatment innovations or research and development projects with focus on the use of standard pulper, hydropulper, high-consistency pulper, and incumbent pulper to treat aluminum-laminated packages, milk cartons and paper meal boxes and examined the repulping efficiency, post-treatment accept fraction pulp handsheet properties (burst and tensile indices), water pollution loading (SS, COD), and unit operation energy consumption of the 4 different treatment facilities. The high consistency pulper and incumbent pulper were design and assembled by our lab. The experimental parameters included pulping time (15, 30, and 45 min), temperature (40 and 50℃), enzyme dose (0, 250, 500, 750, and 1000 mg/L), pulp consistency (for hydropulper, 0.25, 0.5 1, and 2%; for high-consistency puler, 1, 2, 4 and 8%; and for incumbent pulper 1, and 2%).
The experimental results indicated that for the standard pulper, increases in temperature and enzyme dose helped to increase fiber yields. The aluminum- laminated liquid pak had yield increased from 50% to 57~73%; milk cartons fiber yield increased from 65% to 72~87%; paper meal boxes yield increased from 65% to81~89%. Enzyme doses higher than 250 mg/L showed significant effects. For hydropulper and high-consistency pulper, increases in pulping time helped pulping efficiency. At 2% consistency, hydropulper acting on paper meal boxes had maximum yield of 77%; whereas the same raw material treated with high-consistency pulper at 8% consistency produced an yield of 85%. The incumbent pulper, due to insufficient pulping time, had low fiber yields, however, the separation of PE and aluminum foil were fairly clean.
Estimates of water pollution loading indicated that the SS of effluents from hydropulper, high-consistency pulper and incumbent pulper for the aluminum- laminated liquid paks were respectively 59.1, 240.0, 157.4 mg/L; those for milk cartons were respectively 167.3, 223.3, and 302.2 mg/L; and those for paper meal boxes were respectively 138.6, 166.5, and 153.3 mg/L. The effluent COD of the 3 pulping systems for the aluminum-laminated liquid paks were respectively 2182.0, 2153.5, and 601.8 mg/L; those for milk cartons were 2094.1, 2014.0, 645.5 mg/L; and those for paper meal boxes were 2554.9, 2480.8, 932.9 mg/L.
The unit operation energy consumptions of hydropulper, high-consistency pulper, and incumbent pulper for the aluminum-laminated liquid paks were estimated to be respectively 3604.4, 8972.6, and 1453.8 kWh/ton; those for milk cartons were 3681.0, 5270.6, and 1453.8 kWh/ton; and those for paper meal boxes were 5077.0, 3763.3, and 7502.2 kWh/ton, respectively.
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