A thesis proposal submitted in partial fulfillment of the requirements for the degree of Master of Engineer in Pulp and Paper Technology, School of Environment, Resources and Development

Thesis (M. Eng.) - Asian Institute of Technology, 2011

Effect of broke dosage in stock preparation and end products properties had been studied. This experiment using 3 different broke sources; copy broke, offset broke and mix broke. Broke is used to replace short virgin fiber from 0%, until 100%. Moreover, broke effect are observed based on 2 kinds of paper products: copy products and offset products. Both of products are made by different refining energy and chemicals dosage. Copy products are produced with chemical additive dosage 23% (Cationic starch 0.5%, AKD, C-PAM and A-PAM 5%, Bentonite 0.35%, GCC and PCC 11%) and 380 freeness target. However, offset products is made by 360 freeness target and 19.2% (Cationic starch 0.7%, AKD, C-PAM and A-PAM 5%, Bentonite 0.35%, GCC and PCC 9%) chemicals additive. The handsheets are made in laboratory scale by using fresh water and white water circulation. In the first, slurry of raw material not only broke but also acacia and pine fiber are checked to describe the start condition when making paper is started. After that, handsheets are made from replacing acacia by broke are checked by standard method and room condition in the laboratory. Result in this study indicates that replacing acacia virgin fiber by broke in every dosage impacts on furnish such as drainability, zeta potential and charge density. Moreover, adding broke may have some benefits but also some harmful effects for end product properties. Reducing strength properties, worse formation and rougher paper are caused by adding more broke in the process. On the other hand, higher optical properties of paper such as opacity and brightness can be obtained by adding broke.