A case study of the possibility, consequences and synergies for Södra Cell Mörrum to invest in a steam turbine

Abstract: The purpose of this study was to investigate whether Södra Cell Mörrum, SCM, could invest in a steam turbine to produce profitable electricity from excess steam, which is currently being released into the atmosphere. Furthermore, this study investigated the potential side effects from this installation and suggests solutions. This study was conducted in two phases: collecting data which was then sent to a range of suppliers for budget offers and performance estimates. The next phase was to evaluate and quantify the profitability of the potential investment. Results of the study proved that a normal Rankine Cycle turbine was more profitable for SCM than an Organic Rankine Cycle, ORC. This was mainly believed to be because of heat losses occuring when the steam is used to heat the organic medium used in the ORC turbine. The overall electricity produced by the steam turbine, will, according to the analysis, vary between 13 992 500-42 251 600 kWh/ year. While the financial key values considered varied significantly with modified variables, an investment is believed to be profitable within a realistic time perspective of 10 years. Conclusions made from this study suggests that approximately 186,1 - 13 098 ton CO2 emissions can be prevented by installing this turbine, dependant on which reference country is used. The potential production of electricity is equivalent to % of SCM’s production and consumption, respectively. Furthermore, a synergy is quantified from the installation which will either generate more electricity or enable a larger amount of bark to be made available for sale. A mix between the two will most likely occur in the future, whereas the latter is proven to be most profitable. This, as well as the future profitability, will depend on the spot price and the certificate price of electricity.