Introduction

Task 16 take a whole system approach to decarbonising steelmaking processes. This task will integrate with Hub partners whilst focussing on the quantum yield within steelmaking processes by coupling raw material inputs, in-process reactions and by-product outputs with energy.

Research in Task 16 will build on the Task 2 knowledge of non-fossil fuel carbon (NFF-C) feedstocks in terms of their thermal chemistry and volatiles release but extend process understanding to the solid reactants in blast furnace, electric arc furnace and direct reduction technologies (i.e., coke, iron, iron oxide sinter etc.), focussing on optimising circular economy interactions between reactants and energy.

The overall quantum yield (i.e., the energy in versus energy used in the process) of BF ironmaking is very low and this is not currently addressed in other developing technologies. Whilst the quantum yield of visible light processes is quite well understood, the way in which infrared radiation is absorbed and/or reflected and/or emitted and/or transferred is much less well understood. This is surprising because this holds one of the major keys to decarbonising all energy intensive industries.

In this context, Task 16 will study:

1. Simple but novel heat recycling processes

2. The quantum yield of current process and improved processes

3. Optimisation of infrared absorption, reflection, emission and transfer processes

4. Low temperature routes to ironmaking through catalysis

Task 16 will study how we can improve the quantum yield of infrared harvesting in dynamic reactor systems under extreme conditions. Previously, related approaches have been used to significantly intensify other manufacturing processes, whilst running at much lower temperature. The plan is to be open-minded regarding energy vectors as long as they can be harvested and recycled. Instead, they will be used like the tools in a toolbox and focus on the energy because it’s not just the energy vector, it’s the energy itself that must be considered.

Targets

• To double the quantum yield of blast furnace ironmaking hence halve the CO2 emissions from energy generation (i.e., ca. one third of the total).

• To at least halve the fossil fuel carbon used in electric arc furnaces.

• Research will be applicable to existing blast or electric arc furnace processes which minimises CAPEX costs and offer rapid routes to impact.

• Because the new knowledge relates to energy and energy vectors rather than particular processes, research will also aim to inform developing technologies through better understanding of optimised quantum yield.

Progress to Date

Publication:

· Task 16 have published work on using biomass fuel in iron ore sinter production.

· Completed a journal paper studying non-recyclable waste as an alternative blast furnace reductant.

· Submitted work studying the thermodynamics and energy balance related to upcycling steelmaking off-gases.

· With SUSTAIN partners, Task 16 have submitted a review paper on routes towards net zero sustainable steel production.

Task 16 have also carried out measurements of heat flow within various steelmaking processes (e.g. related to blast furnace sinter and hot dip galvanisation processes). As a result of this, the need for a “mobile” thermal imaging set up has been identified. Task 16 have purchased and commissioned this system and will shortly use it on the commercial galvanising line at Tata Steel Llanwern and then at the pilot scale electric arc furnace (EAF) at the Materials Processing Institute. 

Task 16 are currently working on both physical and chemicals approaches to energy transfer and harvesting processes as ways to improve the quantum efficiency of steelmaking. These technologies should be applicable in parallel within an overall process stream to optimise the overall energy usage. To accelerate progress, Task 16 have used theoretical studies of the thermodynamics and life cycle analysis of different processes, then idealised experimental measurements (e.g. to identify heat flow and process kinetics) before carrying out controlled laboratory experiments. This work will lead then to scale up experiments (e.g. on the pilot scale EAF at MPI).