Optimizing Fiber Quality in Recycled Old Corrugated Containers (OCC) Using Ultra-Fine Bar Plate Technology

This study evaluated the performance of ultra-fine bar refiner plates with a cutting edge length (CEL) of 97 km/s in enhancing the properties of Korean Old Corrugated Containers (KOCCs) compared to conventional plates with a CEL of 37 km/s. While unrefined KOCCs demonstrated compromised mechanical properties except for higher paper bulk, refining with the ultra-fine bar plate significantly improved tensile strength, tear strength, and water retention value (WRV). Although the conventional plate achieved higher stock throughput at lower specific energy, the ultra-fine bar plate proved more energy-efficient for achieving targeted fiber quality enhancements. The observed throughput plateau of the ultra-fine bar plate is attributed to its narrower groove design, which increases flow resistance. Overall, the ultra-fine bar plates offer a promising route for producing high-performance recycled paper by balancing refining energy inputs and fiber quality improvements.