EXPERIMENTAL AND THEORETICAL INVESTIGATIONS FOR THE DESIGN OF SCRUBBERS IN HEAT-RECOVERY FROM PAPER MACHINES

Most of the energy consumption in paper machines takes place in the dr yer section. The purpose of the heat recovery system is to reduce the consumption of primary energy in the paper machine by utilising waste energy from the process in an economically profitable way. To provide the necessary information and computer tools to aid engineering design ers, experimental and theoretical investigations have been carried out for a scrubber. Experiments were conducted in a 0.710 m diameter and 3 m high column. The experiment was based on the exchange of mass and heat transfer between humid air which is moving from the bottom to the top of the column and drops which are raining down. A classical physi cal model has been developed to predict the heat and mass transfer bet ween phases. Experimental results agree well with the prediction. The physical model was used to predict the optimum operational condition f or an industrial-type scrubber. (C) 1997 Elsevier Science Ltd.