Pulp mill aerated lagoons are subject to perturbations owing to the chang-ing composition of the effluent and variations in climate. Such stresses may affect microbial activity and the biodegradation of chlorinated organic compounds. Studies revealed thatvariation in the culturable microbial population in a northern Ontario kraft pulp mitl la-goon is related to process parameters (w...

The process industries exhibit an increasing need for efficient management of all the factors that can reduce their operating costs, leading to the necessity for a global multi-objective optimization methodology that will enable the generation of optimum strategies, fulfilling the required restrictions. In this paper a genetic algorithm is developed and applied for the optimal assignment of all...

BACKGROUND Bamboo is a highly abundant source of biomass which is underutilized despite having a chemical composition and fiber structure similar as wood. The main challenge for the industrial processing of bamboo is the high level of silica, which forms water-insoluble precipitates negetively affecting the process systems. A cost-competitive and eco-friendly scheme for the production of high-p...

Steam explosion has been proposed for a wide range of lignocellulosic applications, including fractionation of biomass, pre-treatment of biomass for ethanol production, or as an alternative to conventional mechanical pulping. Nevertheless, a steam explosion process could also be used as pretreatment before chemical pulping, expecting a reduction in cooking time due to the open structure of the ...

The feasibility of enhancing the efficiency of the kraft pulping operations while at the same time evolving the process into a biorefinery, and thus producing hemicelluloses together with paper products, was studied. Hardwood chips (Eucalyptus grandis) were pre-treated with green liquor prior to pulp production. At optimal pre-treatment conditions, the pH of the resulting extract was 7.8, the w...

Aim of the study: The ability of NIR spectroscopy for predicting the ISO brightness was studied on unbleached Kraft pulps of Acacia melanoxylon R. Br. Area of study: Sites covering littoral north, mid interior north and centre interior of Portugal. Materials and methods: The samples were Kraft pulped in standard identical conditions targeted to a kappa number of 15. A Near Infrared (NIR) partia...

Rice straw was cooked with three levels of alkali content (12, 14 and 16%) in cooking liquor by soda-organosolv (ethanol, diethylene glycol, dimethyl formamide) process. The effect of alkali addition on yield, kappa number, brightness and viscosity of organosolv unbleached pulps was studied. The TCF bleachability of these organosolv pulps and kraft pulp was carried out using a simple three stag...

The closure of water circuits within pulp and paper mills has resulted in a higher contamination load of the final mill effluent, which must consequently be further treated in many cases to meet the standards imposed by the legislation in force. Different treatment strategies based on advanced oxidation processes (ozonation and TiO2-photocatalysis), and their combination with biological treatme...

Wood polymer composites (WPC) are sensitive to moisture because of the hydrophilic nature wood fibers. The main objective this study was improve dimensional stability WPCs by coating. Polypropylene and polylactic acid were reinforced three pulp fibers (kraft, thermomechanical (TMP), chemothermomechanical (CTMP)) at fiber contents (50, 60, 70% w/w). resulting coated using two commercial coatings...

We introduce the notion of super-state automaton constructed from another automaton. This construction is used to solve an open question about enumerative sequences in rational trees. We prove that any IN-rational sequence s = (sn) n0 of nonnegative integers satisfying the Kraft inequality P n0 snk ?n 1 is the enumerative sequence of leaves by height of a k-ary rational tree. This result had be...