Abstract

Paper making is an energy intensive process: in 2006, UK paper makers used an average of 4,060 kWh of primary energy to produce each of 5.63 million tonnes of paper products, which thus used 22,857.8 GWh of energy. A paper machine is a very multivariable process and yet it is typically controlled using traditional single loop control strategies which have difficulty comprehending and compensating for the effect a number of variables may have on each paper quality variable. Consequently, in normal operation many potentially useful control variables remain unused.

The seminar will address the question of how much energy saving benefit multivariable control technology can provide in paper making. Present indications are that at least a 20% reduction may be possible. The energy reduction delivered by two recently implemented APC systems on full scale commercial paper machines in Australia and Canada will be reported. The objectives of two recently initiated university-based research and development projects, aimed at better understanding the potential for reducing energy use in paper making, will also be reviewed.

Paul was born and grew up in the Hutt Valley of New Zealand. He completed a BE (Chem) degree at the University of Canterbury NZ while holding a Tasman Pulp & Paper Co student bursary and he worked at Tasman (now owned by Norske Skog) after graduating. He completed a PhD at Cambridge University in advanced control systems engineering and then embarked upon an academic career in the UK and in NZ. Through his NZ university positions he undertook a number of modelling, simulation and controller design projects in pulp & paper, in electrical energy supply and demand, and in a variety of other industry sectors. This work led Paul into consulting engineering and for 12 of the next 16 years he was responsible for launching performance improvement initiatives in industries world-wide, using multivariable modelling and advanced process control. He and the engineers he has worked with in various companies are all currently employed by Perceptive Engineering, based a little south of Manchester in the UK. More recently he has reduced his industry involvement to allow time to take up part time positions in the Cambridge University Engineering Dept (where he is a Senior Research Fellow) and in the School of Engineering and Computer Science at Victoria University of Wellington (where he is Professor of Control Systems Engineering).