Tata steel has the capacity to produce 5 million tonnes of steel each year. Steel provides much of our necessary infrastructure, supporting everything from cleaner building technologies, through the transition to electric vehicles and even the production of renewable energy technologies themselves. If something isn’t made from steel, you can usually find that it was made with steel. However, steel production itself releases large amounts of greenhouse gasses, with Port Talbot being the largest industrial CO2 emitter in the UK. The industry is committed to reaching net zero, so is exploring all opportunities to improve efficiency of processes and reduce emissions and environmental impact.
Around 3.5million tonnes of the steel produced at Port Talbot each year goes into higher value downstream process and all of this must pass through the reheat furnaces, which are a pivotal part of the rolling process. Improving the performance will increase the throughput, yield, reduce cost and the environmental impact significantly.
This project aims to achieve the optimum free oxygen in Port Talbot’s reheat furnaces. In order to address the issue, Tata have recently installed a state of the art laser spectrometer to determine gas compositions in-situ during furnace operation. This studentship supports that work by determining the optimum oxygen needed for the most efficient combustion in PT Reheat Furnaces.
The student would develop a comprehensive understanding of combustion stoichiometry and oxidation kinetics to investigate how potential changes to the gas system might impact energy efficiency and product quality. At temperatures exceeding 1200°C, even small changes in free oxygen concentration can have a significant effect on product quality and yield, not to mention energy consumption and throughput. The student would have a number of options at their disposal (some examples below) for controlling free oxygen in the reheat furnaces, utilising the new spectrometer to validate the benefit of each method in real time.
- Damper control: make improvements to the damper controller to reduce tramp air ingress (caused by negative pressure scenarios)
- Fuel pressure control: make improvements to the controller to stabilise incoming flow to maximise efficiency in combustion
- Fan speeds: alter/trim combustion air flowrates/pressure setpoints based on incoming atmospheric analysis data to ensure exact stoichiometry at all times
- Air-fuel ratio control
- Investigate the benefits/challenges of oxygen enrichment.
The student will ultimately play a significant role in developing a robust method to control the free oxygen, recognising the need to reach the optimum condition in the reheat furnaces to balance product quality, yield, throughput, and energy consumption. Alongside the traditional PhD research outcomes, they will be contributing real, tangible value and impact to the sustainability of a key industry required for other parts of our national infrastructure to meet net zero goals.