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2026 Vol.58, Issue 2

Review

Navigating the Energy-Quality Trade-Off of Refining Process in Stock Preparation: Advances in Refining Theory and Optimization for Sustainable Papermaking (Part II)
Chul-Hwan Kim1†
1Department of Forest Products, IALS, Gyeongsang National University, Professor
†Corresponding Author: E-mail: jameskim@gnu.ac.kr (Address: Department of Forest Products, IALS, Gyeongsang National University, Jinju, 52828, Republic of Korea)
30 April 2026. pp. 5-25
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Abstract

This second part of the two-part series presents the theoretical foundations and operational strategies for optimizing pulp refining to address the energy–quality paradox in sustainable papermaking. Building on the mechanisms and plate technologies reviewed in Part I, this paper introduces quantitative frameworks—including Specific Edge Load (SEL) and Specific Surface Load (SSL)—to characterize refining intensity and guide fiber development. The analysis highlights the benefits of low- and ultra-low-intensity refining with ultra-fine bar patterns, which improve fibrillation efficiency, reduce fiber cutting, and offer significant gains in strength properties while lowering energy consumption and extending plate life. Key operational variables such as consistency, pH, temperature, and bar-crossing angle are evaluated alongside system configurations suitable for various mill scales and furnish types. Emerging digital tools—including real-time sensors, automated control loops, and digital twin systems—are discussed as enablers of intelligent, energy-efficient refining. Integrating theory, plate design, process control, and digitalization, this framework provides practical pathways for mills to reduce energy use while enhancing paper quality and operational sustainability.

Keywords
SEL
SSL
low-intensity and ultra-low-intensity refining
refiner plate geometry
fine bar plate
grade-specific refining
sustainable papermaking
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Information
  • Publisher :Korea Technical Association of The Pulp and Paper Industry
  • Publisher(Ko) :한국펄프종이공학회
  • Journal Title :Journal of Korea TAPPI
  • Journal Title(Ko) :펄프종이기술
  • Volume : 58
  • No :2
  • Pages :5-25
  • Received Date : 2026-01-23
  • Revised Date : 2026-02-09
  • Accepted Date : 2026-02-09
  • DOI :https://doi.org/10.7584/JKTAPPI.2026.4.58.2.5
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