New approaches to power modulation at TRIMET Hamburg

Abstract

TRIMET ALUMINIUM AG acquired the Reynolds cell technology P19 smelter in Hamburg in 2006 after a complete shutdown. The 135 ktpa smelter was restarted successfully in 2007 and has been in continuous operation since. The increasing spread of the energy price during night and day time, as well as long term price difference have lead to novel approaches to decrease the average energy price by operating the smelter with non linear energy input. Theoretical calculations were done to estimate the maximum energy difference of various cell states. Experiences were made of the impact on performance vs. modulation range. This paper presents the theoretical background as well as practical data of a smelter operating with power modulation.