Electrification in Process Industry - The Role of Process Integration and Future Energy Market Conditions

Licentiate thesis, 2020

Electrification of industrial processes is a frequently discussed strategy to reduce greenhouse gas emissions from energy-intensive process industries and is highlighted in many roadmap studies. Electricity is a versatile energy carrier that enables a broad variety of options in which existing process unit operations are replaced with electricity-driven alternatives. However, the implications in terms of greenhouse gas emission reduction potential and cost when integrating such new electrification technologies are not obvious due to often complex interactions between energy flows in existing industrial plants. Understanding these implications and interactions is not only important in order to assess electrification in comparison with current process configurations, but also to allow a comparison with other greenhouse gas emission reduction strategies.

In this thesis, a bottom-up framework to assess opportunities for electrification of energy-intensive industrial processes in terms of greenhouse gas emissions and costs was developed. One particular novelty is that the framework includes heat integration studies with pinch analysis tools to analyse how potential changes in heat surpluses or demands associated with the replacement of a fuel- or heat-driven unit operation by a new electricity-driven process affect the heat recovery potentials and utility demands of the overall site. Furthermore, energy flows between the process site and the background energy system are considered and the use of scenarios is introduced in order to assess the impact of electrification options under different possible future energy market conditions. The framework was tested and validated in three case studies for different industrial processes. In these case studies, different parts of the existing processes-related systems (e.g. the reactor system or utility system) were assumed to be electrified, highlighting different aspects of the proposed assessment framework.

The results emphasise that electrification may significantly change the heat flows through a process site and that detailed heat integration studies are required to capture these effects. Another finding is that the underlying assumptions for future energy market scenarios have a strong impact on greenhouse gas emission reduction potentials and cost. The framework can be used to compare electrification with other process greenhouse gas emission reduction measures and to support policy and industrial decision making.