Utilising waste heat for steam generation within an integrated steelworks: A methodology for power generation and CO2 reduction

UK energy prices have doubled over the last decade, which has driven the UK Iron and Steel Industry to invest in energy efficient technologies. However, even with these relatively high prices the industry still finds it difficult to build a business case to justify waste heat recovery projects. The Steel Industry has large quantities of waste heat and there are technologies readily available for its capture, but often the issue has been finding a cost effective ‘end use’. Individual schemes incorporating both capturing and an ‘end use’ for the waste heat often incur high capital costs with resulting long payback times. This paper defines the development of a strategy and methodology for the utilisation of waste heat recovery in a UK based Steelworks. The methodology involves the utilisation of an existing asset to link the possible waste heat schemes together with a single ‘end user’ thus limiting the capital requirement for each subsequent project. The paper further discusses the fact that on an individual basis the proposed strategy does not provide the most energy efficient solution for each project, but it provides the most cost effective solution. The developed strategy stimulated significant capital investments for the steel works discussed in the case study and will generate over 12 MWe and save over 52,500tonnes of indirect CO2 emissions per annum