داخلي CMP بررسي ويژگي هاي خمير جوهرزدايي شده كاغذهاي روزنامه و مجله باطله داخلي در مقايسه با خمير

A study on the Properties of Local ONP/OMG Deinked Pulp in Comparison With Local CMP Pulp

Randomized samples have been prepared from local Old Newspaper (ONP) and Magazine (OMG) with their specified mixtures having been repulped, deinked and subsequently bleached with hydrogen peroxide. Three levels of paper mix (100, 70/30 and 50/50 percent of ONP/OMG), 2 types of chelating agent (DTPA, EDTA), and 3 levels of calcium ions (1,1.5 and 2%) have been studied as variable parameters. Brightness values of the deinked pulps, before and after bleaching, and optical and mechanical properties of bleached deinked pulps have been measured and compared with local hardwood CMP pulp. The results have shown that although the brightness of CMP pulp is higher but its mechanical properties are lower than deinked pulp at similar freeness. Normalization results have shown that the deinking treatment using 50/50 ONP/OMG, EDTA and 1% calcium ion charge won the highest score or the best optical - mechanical properties as compared to local hardwood CMP pulps. As a result, it can be predicted that the bleached deinked pulp prepared under optimum conditions as indicated in this research, can be used as a mixture furnish with local CMP for making newsprint paper.