| 摘要 |
<p>PURPOSE:To obtain the excellent regenerated pulp high in whiteness by adding a hypochlorite salt without using an alkali agent in a process for disaggregating printed waste paper in a specific concentration. CONSTITUTION:In a process for disaggregating printed waste paper by adding water and stirring the mixture to control the concentration of pulp to 3-10wt.%, 0.1-2.0 pts.wt. (converted into effective chlorine) of a sodium hypochlorite solution is added to 100 pts.wt. of the waste paper with stirring without adding a conventional alkali agent such as an alkali hydroxide. While the pH and temperature of the bath are therein controlled to 2-7 and ordinary temperature-60 deg.C, respectively, the waste paper is subjected to a regeneration treatment (and subsequently subjected to a bleaching treatment in an alkaline hydrogen peroxide bath) to obtain the regenerated pulp high in whiteness. The method enables to avoid the complication of the operations without remodeling conventional installations and without leaving the smell of chemical agents.</p> |
