The importance of biotechnology in waste papers processing

Over the past few years, due to the shortage of forest resources as well as the increasing consumption of paper and paperboard, many pulp and paper manufacturers have developed the use of different sources of recycled (secondary) fibers. Therefore, recycling of paper is an effective and eco-friendly way to preserve forest resources, which eventually save the natural diversity and energy. The use of biotechnology in various sectors of the cellulosic products industries such as bio-pulping, bio-bleaching, bio-deinking, bio-wastewater treatment, etc. has been considered and good achievements have been obtained in this field. One of the most important applications of biotechnology in the cellulosic industries is the use of enzymes in the processing of recycled fibers. The use of enzymatic technologies, as environmental friendly process, has led to changes in industrial processes as much as possible and indicated great potential in solving many problems of recycled fibers, especially problems related to waste paper deinking, pulp drainage rate, fiber hornification, refining and stickies materials. In general, deinking with enzymes under acidic or neutral conditions declines the chemicals usage and reduces the yellowing of recycled paper under conventional alkaline deinking conditions. Today, the use of cellulosic enzymes (cellulase and hemicellulase) and oxidative enzymes (such as laccase) as well as amylase and pectinase have shown acceptable results for deinking different types of waste paper and most experiments in semi-industrial as well as industrial units have shown that deinking with them can reduce the cost of chemicals, increase the separation of ink particles