Cooking Variables in Recycling Newsprint

The purpose of this paper was to compare the effect of some cooking variables on the brightness of the final sheet and the yield per cook in recycling newsprint. The cooking variables examined were: the kind of cooking chemical, the amount of cooking chemical, and the cooking temperature. The cooking variables, that were held constant, were pressure, time, agitation, and consistency of the cooks. The newsprint was cooked in an apparatus similar to a hydrapulper. The brightness decreased with both increased temperature and increased percent addition of chemicals. The yield decreased with both, increased temperature and increased percent addition of chemicals