Computational Modelling and Optimisation of Carbon Capture Reactors

This programme is proposed to answer the EPSRC call on "Carbon capture and storage for natural gas power stations" by forming a close partnership between the University of Southampton and E.ON. The proposed research has a strong focus on industrial needs by integrating with the industrial partner's existing activities for developing CCS technologies suitable for commercial gas power plants. E.ON is generating around 10% of the UK's electricity and is committed to reducing its CO2 emission by 50% by 2030 (1990 baseline). E.ON has setup a dedicated CCS unit to address the technical challenges while one of the priorities is to develop CCS technologies suitable for natural gas power stations. This research specifically targets at natural gas power plants, which has a lower concentration of CO2 approx. 4% compared to 13% from coal-fired plants, and harder to extract, representing the most challenging case for CCS.

Carbon capture and storage involves separating the CO2 from emissions so it can be transported and stored away from the atmosphere. The most commercially viable approach to be fitted in natural gas power plants is the post-combustion capture which absorbs CO2 from the flue gas using a chemical reaction - also known as scrubbing, which E.ON has been actively pursuing and will be the focus of this research. Whilst research on the chemical processes has been taking place for several decades, CFD modelling of the reactor is a recent development. E.ON has recognised that CFD plays a vital role in the optimisation of current CCS reactors by including more CFD research in their future research strategy. University of Southampton is a prime place for CFD based research while the School of Engineering Sciences currently holds £5M CFD focused EPSRC projects. The combined expertise forms a strong academic and industrial partnership to tackle current barriers of reactor scale-up in carbon capture using advanced CFD models.

By addressing all the challenges outlined in the EPSRC call, this research aims to design an optimised reactor using a novel CFD modelling approach that is capable of achieving in excess of 90% CO2 absorption whilst ensuring the cost of service energy is minimised to below 35%. The new concept idea will incorporate improved mixing designs and improved heat transfer whilst reducing reactor size. It is planned through the enhancement of current CFD multiphase models to incorporate reaction and the inclusion of flow control devices that an optimal structured packing arrangement, which promotes the reaction process whilst reducing pressure drop, can be found. This project will not only produce conceptual ideas developed through enhance CFD methods but will also perform tests, in a lab-scale reactor, to determine its validity with respect to its flow dynamics and would potentially lead to the production of intellectual property.

Electricity generation is the largest source of CO2 emissions in the UK and currently represents a third of total emissions. This research has the potential for a very large impact on society by developing a cost-effective technology for the reduction of CO2 emission from power plants.
In general aspect, amine scrubbing has the potential for wide applications. It can be utilised in both pre- and post-combustion technologies, suitable to new and existing plants. Furthermore, it is adaptive to the emissions from different fuel reactors, i.e., natural gas, coal, biomass etc., and also different conversion techniques such as gasification and combustion. Therefore, the outcome of this project would be applied for a variety of conversion technologies which are already being utilised in the energy sector throughout the UK and also worldwide.
In technology aspect, counter-current absorbers and stripper configurations are also used for other chemical processes such as the production of ammonia. This process is vital for the formation of amine solutions which is used during the carbon capturing process. Therefore, the optimised absorber design could be extended to this process which would further reduce the costs and improve efficiencies over a wider range of the carbon capturing process beginning with solvent production.
In the modelling aspect, the code to be developed will be the state-of-the-art with the incorporation of multiple phases into periodic modelling which is currently not available. Furthermore, reactions will be enabled to allow for mass transfer between phases to account for the absorption processes that take place in the reactor. Demonstrating such modelling capabilities will not only enhance research in the modelling of carbon capture but also other processes that exhibit a strong reactive behaviour. Successful application of these advance models demonstrates the capabilities of CFD and its ability to aid engineering design, process optimisation and technology breakthrough for industry.

This project enables the formation of a close partnership between the University of Southampton and E.ON, so technologies developed can be explored commercially in the UK and knowledge gained can be shared around the world. The investigators have extensive experience in Industrial CASE Award, KTP, TSB and EU projects with industrial partners such as BOC, Praxair and Air Liquide, etc. In relevant clean energy research, we have been working closely with Lurgi (a leading technology provider for gas cleaning and CCS technologies) and involved in their research and development of advanced coal gasification plants in China. In South Africa, we are working with Sasol (a leading company in commercialization of clean coal technologies) in EPSRC energy research (EPSRC EP/G034281/1) project. In this new project, we will continue to identify appropriate mechanism for industrial collaborations according to industrial and technical requirements.