NEWSPRINT FROM WHOLE JUTE

摘要

The paper presents the final findings and conclusions of the project "Newsprint Paper from Green Jute". The project was undertaken as a co-operation between Bangladesh Chemical Industries Corporation (BCIC), Dhaka University (DU) and the Pulp and Paper Group at the Department of Chemical Engineering at the Norwegian University of Science and Technology (NTNU). The project was financed by a grant from the Norwegian Agency for Development Co-operation (NORAD). The practical work was undertaken at the NTNU laboratories during the period 1997-1999 in two phases. The objectives of the project was to design, test and verify into a pilot scale level; a simple, economically viable, and environmentally friendly process for making newsprint grade paper from the whole green jute plant. A prime goal has been to develop a continuous process being as flexible as possible. Ail the process stages are operated at atmospheric pressure. The energy and chemical consumption is modest, without any need of recovering the chemicals. We have not looked specifically into any effluent treatment, but we do recommend a biological treatment plant. The suggested process starts from a raw material of dried whole jute. To secure a continuous supply of jute throughout the period from one harvest to the next, the jute should be sun dried in bundles to a dry solids content of at least 80%. After chipping, the whole jute is washed to remove black seeds arid other discoloured impurities. The washed jute is then steamed and impregnated with alkali and hydrogen peroxide before being crushed in a disc refiner. Chelating agents are added to reduce peroxide degradation caused by heavy metal ions present.