There is a growing drive to modify conventional coal burning thermal power plants so that a greater diversity of fuels can be used at higher, more efficient temperatures. This presents challenges with respect to materials selection for critical components such as superheaters. Operation parameters control the steam side degradation (i.e., oxidation and subsequent spallation) of superheater tubes. The predicted change in operating mode to a more cyclic nature, whether due to the need for responsive flexibility with increased use of wind and wave power generation or due to degradation induced limitations from new forms of fuel, will require a change in approach to plant design and lifing.
The potential threat posed by climate change due to high emission levels of greenhouse gases has become a major stimulus for renewable energy sources. In the UK, the target is to generate 10% of electricity need from renewable sources, of which biomass will form a significant component. When produced, biomass emits roughly the same amount of carbon during energy conversion as is taken up during plant growth. The use of biomass as a fuel therefore does not contribute to the build-up of CO2 in the atmosphere.
Unfortunately, biomass introduces aggressive species into process environments that result in degradation of boiler systems and alteration of typical heat flux to the steam generator. Oxide spallation during shutdown of boilers can lead to tube blockage from debris causing local overheating and tube rupture during restarts. This is a major concern as unscheduled/extended shutdowns can cost operating companies hundreds of thousands of pounds for each day that the plant is inoperable.
The ultimate objective of this work is the development of a model for steam side oxidation growth and spallation for steels both prior to and after the initial spallation event based on laboratory observations in simulated cyclic steam oxidation experiments. Although the kinetics of oxide growth under steam environments are well known for the situation where the scale remains intact, the details of these new scale growth kinetics, eventually leading to subsequent spallation are currently unknown.
This studentship is sponsored by Alstom Power Ltd and is part of the Engineering Doctorate Centre in Efficient Fossil Energy Technologies which aims to produce research leaders to tackle the major international challenges over the next 15 years in implementing new power plant to generate electricity more efficiently with near zero emissions.
The EngD training provides:
- Fully paid fees
- A non-taxed stipend of up to £20,090
- International travel for conferences and attending international summer schools
- Preparation for high-level careers in the energy sector
Students should be of high academic calibre and merit and due to funding restrictions must satisfy the UK residency requirement. They will also need either a first class or 2.1 degree in a relevant subject such as: Chemical, Environmental Engineering, Chemistry, Materials Science and Metallurgy.
To apply, please send a CV with a covering letter to Dr Brian Connolly, School of Metallurgy and Materials, University of Birmingham, Email: b.j.connolly@bham.ac.uk