Ångbalanser och elproduktion i Norrsundets sodahus

Abstract

This master thesis has been done at Stora Enso`s Pulp Mill in Norrsundet. Observations of variations in their electricity production and consumption have been made. The main purpose of this study was to explain these variations and also to give answers how to maximise their electricity production. Data from different historical periods have been chosen and studied. Simulations of the chosen periods have then been done in the simulation program GateCycle, which is developed to perform analyses of thermal power systems. The purpose of the simulations was to deepen the understanding of the periods and also to find unreasonable data among them. The electricity production is dependent on the steam consumption and due to the study there are normal variations in the electricity production and variations due to disturbances in the process. In the cogeneration system there are also some unreasonable ways of running the factory. The turbines are not designed for the conditions in the factory and in periods of high steam consumption electricity cannot be produced in proportional amounts. If the turbines had been designed for the conditions in the factory a larger amount of electricity could have been produced.