Refining Technologies and their Impact in Natural Fibers: A Brief Review

Abstract

Aims: Review the most relevant and available technologies for refining processes considering their commercial availability and fiber manipulation and quality control. Review Design: This review study was caried out focusing on a short and concise scientific literature background review in scientific periodic and published background information. Summary: To access the polymer matrix in the fiber wall for many biomasses, the most usual process is chemical delignification. However, besides the chemical delignification, the interior of the fiber wall and the fiber surface structures are also affected by mechanical shear stresses, such as the refining process, which is an important treatment in papermaking to increase sheet strength. At the microscopic level of fibers and fiber flocs, refining effects are dependent on the magnitude and frequency of deformations. The refining process evolved in this process will be affect according to the disk designer and the refiner equipment structure. There exist many types of refiners utilizing different technologies for fiber individualization and fibrillation. Disk and conical refining are the main technologies available commercially and in the existent pulp and paper industries all over the world. Generally, the disk refiner is a low-cost machine. It can be classified into two groups: the single disk refiner and the multiple disk refiners. Fiber Quality Analyzer (FQA) have been used as strategy to control quality and enhance final product quality in these industries and their affiliated users. Conclusion: This review paper will concisely bring the understanding of the fiber organization and cell structure and how to access these fibers and change their properties according to the available technologies in the market. Finally, elucidating the shear forces evolved in the process and how they act to complete the refining process.