A mill test and a study were carried out to provide a benchmark as to what is the best debarker performance achievable on frozen wood with properly adjusted debarker settings and well-maintained equipment. The test results have shown that:
The fibre to bark ratio decreased to 12.7% from the 20.9% observed in a previous Forintek study of sawmills with average debarker performance.
The lumber value recovered from logs was 10.7% higher than that achieved with average debarking, and the corresponding lumber volume increase was 10.4%.
The debarker removed 97.3% of the bark volume.
The fibre loss was 1.2% .
For a sawmill processing 100,000 m3 of logs during a winter period of three months, losses attributed to poorly operated debarkers can amount to as much as $1.4 million.