A breakthrough in energy reduction in thermomechanical pulping of white birch

The effect of static mechanical compression of white birch chips in trans-a xial direction on the characteristics of thermomechanical pulping (TMP) has been studied. Scanning electron microscopic examination indicated that fib re separation and delamination of cell wall lamellae, particularly in the S -1 zone could be induced to the chips prior to refining. The TMP results sh owed significant savings in refining energy and substantial improvement in physical properties of paper. The advantages of static compression were muc h more beneficial than those produced by conventional screw-press compressi on.