UTILIZATION AND RECOVERY ANALYSIS OF OAK LOGS IN A MODERN WOOD PROCESSING PLANT

Abstract

This paper analyzes the quantitative and qualitative recovery of pedunculate oak (Quercus robur) logs processed in the modern sawmilling facility of “Drvoprodex” d.o.o. in Srbac, Bosnia and Herzego­vina. The research was conducted through a combination of direct measurements during two operational shifts, encompassing 185 logs and company-maintained production records. Logs were classified into three quality grades, with detailed analysis of dimensions and produced assortments, including lamellae (grades A–C), rustic-grade elements (R class), and friezes. The overall recovery from debarked log volume reached approximately 30%, aligning with the lower end of typical industry expectations for oak flooring production. Friezes dominated in quantity (2,376 pcs), particularly in 70 mm width, while lamellae and R-class ele­ments showed optimal yields at 135 mm and 215 mm widths. Regression analysis confirmed a statistically significant positive influence of log diameter on both recovery rate and daily processing volume. While advanced equipment such as a band saw head rig, CNC optimizer, and multi-blade rip saws are employed, several older machines occasionally limit throughput, underscoring the need for further modernization. Importantly, about 70% of the log volume remains as sawmill residue, including slabs, edgings, sawdust, and bark. Recommendations are made for systematic valorization of these co-products: coarse residues can be chipped for biomass energy or panel manufacturing, while sawdust and bark can serve for pellet production or biochemical extraction (e.g. tannins). Enhancing residue utilization would increase material efficiency and economic sustainability, aligning the mill with circular economy principles and near-zero-waste production goals.
Keywords: oak sawmilling, log recovery, wood processing.