AQ pulping and ECF bleaching of hard woods with bark

AQ kraft pulping of hard wood barks, unbarked hard woods and debarked hard woods from juvenile trees has been carried out. Yield, kappa number and viscosity values have been reported. Two bamboo samples have also been studied. The hard woods used are: casuarina equisetifolia, eucalyptus tereticornis, cassia siamea, leucaena leucocephala and bamboos are: dendrocalamus strictus and bambusa arundinacea. The yield, kappa no. viscosity and AA requirements have been determined. DEpD bleaching of AQ treated pulps has been carried out and bleached pulp properties such as yield, viscosity, optical properties, zero span breaking length and FS factor have been reported. The techno-economical feasibility of using bark along with wood in kraft pulping with ECF bleaching has been discussed. The concept of using hardwood with bark in Indian pulp and paper mills, has been highlighted as imperative.