Optimization of Refining in Fine and Specialty Paper Mill Systems, 1996 Papermakers Conference Proceedings

In relation to the other processes involved in papermaking, only drying uses more energy. For example, in the UK alone production is -5 million tonnes, made on 215 paper machines. For those grades requiring significant amounts of energy for the refining of chemical pulps (-2.5 million tonnes) the energy is between 250,000 and 500,000 kW.h/tonne at a cost of £10-20 million. Although approximate the cost involved gives an idea of the potential for saving. Although there are new refiners on the market which offer potential for energy saving, albeit at a penalty in capital investment, there are many ways in which product and process improvement and energy savings can also lx made by means of good practice, e.g. maintenance, correct capacity and filling design. However these opportunities are not always recognised and in many cases new systems have been installed where, by changes in operating practice and attention to condition of equipment, similar improvements could have been made at much lower cost. The practices described in this paper are for refining of virgin chemical fibre and, in some cases, recycled fibre. All examples given are for actual systems making fine and speciality papers. Results are taken from quality control logs and demonstrate the real savings made by a number of relatively low cost modifications.