Green liquor ( GL ) was used as a sulfide rich liquor to impregnate Southern pine wood chips in a pretreatment step for kraft pulping. A central composite experimental design was applied to investigate relationships between pretreatment conditions, chemical absorption, pulping selectivity, and primary pulp qualities. The derived equations provided a correlation between the independent cooking v...

paper mills are characterized as polluting industries, these use pulping process for papermanufacturing, due to which toxic chemicals released into environment. therefore, the biological oxygendemand (bod), chemical oxygen demand (cod) of the emanating stream is high and dissolved oxygen (do) is low. to resolve this predicament, two dominant bacteria bacillus subtilis and micrococcus luteus, an...

The extraction of hemicelluloses prior to pulping is an attractive process to be incorporated in the pulp and paper mills to generate valuable by-products such as xylose and xylo-oligomers in addition to core products. This paper investigates the impact of xylan extraction by dilute acid on cooking conditions, pulp yield and properties during kraft and soda-AQ pulping of Eucalyptus grandis wood...

This study investigates the requirements for modeling of acid sulfite pulping with regard to the recovery of cooking chemicals, especially SO2. Such a model has to predict the temporal change of SO2 distribution on solid, liquid and gaseous phase in the digester throughout the whole pulping process, dependent on the pulping parameters: total SO2, free SO2, liquor-towood ratio, temporal temperat...

An ultrasound-assisted extraction (UAE) method using ethanol was applied for extracting arabinogalactan (AG) and dihydroquercetin (DHQ) simultaneously from larch wood, as a pretreatment for pulping and papermaking. The extraction parameters were optimized by a Box-Behnken experimental design with the yields of AG and DHQ as the response values. Under optimum conditions (three extractions, each ...

The extraction of hemicelluloses, which otherwise would be wasted in the black liquor, can be integrated with chemical pulping processes in a biorefinery approach that will generate a sugar-rich feedstock for production of fuels and chemicals. Extractions of hemicelluloses from sugarcane bagasse under dilute sulphuric acid or mild alkaline conditions were performed, using a central composite ex...

This review analyses the advances of pretreatment with sulfide-containing liquors to modify kraft pulping. In the past several decades, modified kraft pulping has advanced rapidly, based on the principle that high sulfide content at the first stage of cooking would improve both pulp quality and the selectivity of delignification. Pretreatment of wood chips with sulfide-containing liquors (i.e.b...

To further improve the low-frequency broadband sound absorption capability of underwater anechoic layer (UAL) on surface marine equipment, a novel structure with cavities (NSSC) is designed by adding resonators and honeycombs to traditional (SSC). Based principle shear dissipation, original intention design allow more parts viscoelastic material participate dissipation acoustic energy. The appr...

Through the study of forest-pulp enterprise production logistics pulping flow sub-system and production elixir flow sub-system, Petri nets model and the object-oriented model as the theoretical basis, and puts forward the enterprise production logistics subsystem compound model, and discusses the pulping process based on the composite model of logistics balance mathematical principle.

The present study focused on the evaluation of a nonspecific synergistic effect of biogenic silver nanoparticles (AgNPs) in combination with biosurfactants against environmental bacteria and fungi. The AgNPs were synthesized in the culture supernatants of the biosurfactant producer Bacillus subtilis grown in brewery effluent, molasses or Luria-Bertani media. Antibacterial activities were tested...