this study was performed to investigate the effects of refining on the mechanical and optical properties of waste newspaper. waste newspapers were prepared from gorgan ettelaat newspaper agency and were cut to 5 centimeter pieces, and then were soaked with sufficient distillated water. after 1 day fibers were separated by disintegrator and freeness values for each pulp before and after refining...

Abstract Background Pulp refining is an energy consuming, but integral part of paper production with the aim to increase tensile strength and smoothness sheets. Commercial enzyme formulations are used lower requirements by pre-treatment pulp before refining. However, a high number different commercial products available on market containing enzymes varying origin composition, which complicates ...

The review focuses on applications of artificial neural networks (ANNs) in various subsystems of pulp and paper making processes. Some applications are pertinent to modeling of pulping, bleaching and energy conservation process while others are related to control of refining, washing of brown stock, combustion of black liquor, lime kiln operation, grade changes and quality control. A general al...

There is a general interest among paper and board makers to produce lighter and bulkier paper and board products. The aim of the present study was to characterize chemically crosslinked hardwood kraft fibers regarding their potential in making bulky paper and board. Crosslinking agents are molecules that contain two or more reactive ends that form inter-chain covalent bonds with cellulosic hydr...

In a low consistency refiner pulp fibres are trapped between the bar edges of the rotor and stator and worked into the narrow gap between rotor and stator. No refining occurs if the fibres are not trapped. A reduction in fibre trapping is believed to be in the common observation that refining becomes less efficient as the bars wear and lose their sharpness. This paper examines the effect of bar...

in this research, effect of using hornbeam and beech branch woods in admixture with birch stem wood on their cmp pulp properties. using percentage of branch woods, with 20% constant content for birch stem wood, were 0, 16, 40, 56 and 80 in final mixture of hardwoods. the results indicated that cooking time, to reach 85% yield and under same cooking condition, and also refining quantity, to reac...

Kenaf (Hibiscus cannabinus) nanofibers were isolated from unbleached and bleached pulp by a combination of chemical and mechanical treatments. The chemical methods were based on NaOH-AQ (anthraquinone) and three-stage bleaching (DEpD) processes, whereas the mechanical techniques involved refining, cryo-crushing, and highpressure homogenization. The size and morphology of the obtained fibers wer...