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Pulp and paper industry is traditionally known to be a large contributor to environmental pollution due its large consumption of energy and chemicals. To reduce the chemical consumption, rate of delignification was increased by Schizophyllum commune in destructured sample of Dendrocalamus stictus, which was destructured by Impressafiner (compression- cum dewatering process). The extent of delignification was determined and comparison was made between the non-destructured and destructured samples. The influence of physical parameters like incubation time, moisture level, media, media concentration, pH and temperature were also examined during the study. It was found that rate of delignification was significantly 6.43% more in destructured sample than non-destructured sample. Kraft pulping of treated destructured sample shows 2.59 point reduction in kappa number than untreated non-destructured sample. Thus this paper provides an insight of the delignification extent in Dendrocalamus strictus after mechanical operation at varying physical parameters. [ABSTRACT FROM AUTHOR]

Pulp and paper industry use different chemicals to separate cellulose fibre from lignocellulosic biomass for papermaking. The use of sodium sulphide and chlorine during pulping and bleaching processes, have now been classified as the main sources of air and water pollution in the pulp and paper industry. To surmount these problems biological processing, offers potential opportunities for changing the industry towards more environment friendly industry. In the biological pulping process, removal of lignin can be achieved through treatment of lignocellulosic materials with white rot fungi due to their ability to degrade complex and recalcitrant organic molecules and this makes them attractive micro-organism for biodelignification. In the present study biological pre-treatment of Eucalyptus chips was carried out with Schizophyllum commune. The influence of growth parameters like incubation periods, moisture levels, media, media concentration, pH and temperature were also optimized. During the study it was found that Schizophyllum commune shows 14.72% lignin loss within 28 days at optimum conditions i.e. pH (6.0), temperature (25°C), moisture (60%) and molasses concentration (4%). Thus the study will provide an insight to find out economically feasible conditions to commercialize biopulping on large scale. [ABSTRACT FROM AUTHOR]

More than 70 % bleached chemical pulp is produced in India through elemental chlorine-free bleaching in which chlorine-based compounds like chlorine dioxide is a dominant chemical which generates chlorinated organic toxins harmful to the environment. Present studies demonstrate short sequence of bleaching combined with acid treatment, followed by pressurized oxygen delignification. It was found that efficiency of oxygen improved by adding hydrogen peroxide as an additive in oxygen delignification with subsequent treatment with ozone or chlorine dioxide as bleaching agents. It was observed that by using additive in ODL process, pulp can achieve 70±1 (%ISO) brightness. Reduction attains in kappa number 65–70 % as compared to 45–50 % in control oxygen delignification stage. Through AOpZ and AOpD bleaching sequences, full brightness achieved 84–85 (%ISO) without considerable loss in mechanical strength properties compared to DEpD sequence. A potential reduction in COD, color, and AOX was 28, 53.3, and 88 % respectively were observed in AOpZ short bleaching sequence compared to DEpD bleaching. [ABSTRACT FROM AUTHOR]