COLLIMATED CHIPPING TECHNOLOGY IN ORDER TO REDUCE THE ENERGY CONSUMPTION IN MECHANICAL PULPING
It has recently been shown that it is possible to improve the energy efficiency during first stage TMP (thermomechanical pulp) refining by utilizing a modified chipping method (collimated chipping). A patent application regarding this method has been filed and is pending. The modification consists in that the spout angle i.e. the angle between the fibre direction of the wood specimen and the cutting plane, is increased. This paper reports the differences in properties of TMP refined from chips produced at two different spout angles i.e. 30 and 50 with and without the addition of sodium bisulphite (NaHSO3) to the dilution water. It was found that the specific energy input for a certain CSF (Canadian Standard Freeness) value was lower for chips produced at spout 50 but that the addition of chemicals to the dilution water had no influence on the specific energy value for a given CSF value. However, the tensile index and specific light scattering coefficient was substantially higher for handsheets made of the pulp refined from chips produced at spout angle 50 and with NaHSO 3 added compared to handsheets from pulp made from 30 and 50 chips without chemicals added.
Wood chipping Chip damage TMP Sodium bisulphite Energy efficiency
Lisbeth M. Hellstr(o)m Torbj(o)rn Carlberg Per Engstrand Per A. Gradin Ovind Gregersen
Mid Sweden University,FSCN, SE – 851 70 Sundsvall, Sweden
国际会议
International Mechanical Pulping Conference 2011(2011国际机械浆学术会议)
西安
英文
457-460
2011-06-26（万方平台首次上网日期，不代表论文的发表时间）