A Review on Pulping, Bleaching and Papermaking Processes

  • Nidhi Sharma Department of Chemistry, Graphic Era (Deemed to be University), Dehradun, Uttrakhand, India, Paper Testing Division,Central Pulp and Paper Research Institute, Himmat Nagar, Saharanpur 247001, Uttar Pradesh, India
  • Bhawana Department of Chemistry, Graphic Era (Deemed to be University), Dehradun, Uttrakhand, India
  • R. D. Godiyal Paper Testing Division, Central Pulp and Paper Research Institute, Himmat Nagar, Saharanpur 247001, Uttar Pradesh, India
  • B. P. Thapliyal Paper Testing Division, Central Pulp and Paper Research Institute, Himmat Nagar, Saharanpur 247001, Uttar Pradesh, India
Keywords: Raw Material, Chemical Composition, Pulping, Bleaching, Pulp, Paper

Abstract

This paper presents a concise overview of pulp and paper production process, chemical constituents of the paper making biomass, pulping and bleaching processes. Processes related to raw material preparation, washing of pulp, chemical recovery operations, stock preparation and papermaking are described. Significance of chemical constituents of papermaking biomass such as lignin, cellulose, hemicellulose, extractives, ash, water solubility and alkali solubility towards papermaking is explained. Reflections on different types of pulping processes such as soda, soda-AQ and Kraft pulping along with the necessary reactions have been provided. Various sequences of conventional, elemental chlorine free and total chlorine free bleaching along with use of enzymes in bleaching is portrayed. In addition, status of different types ofraw material used in Indian pulp and paper industry is also presented.

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Published
2020-09-15
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