Carbon Capture from Power Plant and Atmosphere

Lead Research Organisation: Heriot-Watt University
Department Name: Institute Of Petroleum Engineering

Abstract

Energy supply for the UK, and for the world, will experience major changes during the next 20 years. Many nations seek secure energy supplies, combined with low costs, and sustainable environmental impacts. Most of world energy currently derives from combustion of fossil fuel. The UK is no exception.In the UK, fossil fuel (oil) dominates transport use, and is difficult to change in the near future. Electricity and heat generation is dominated by gas (41%) and coal (34%), with 20% from nuclear, only 3% from renewables, and 2% imported electricity. This gas and coal will from now onwards largely be imported, paying costs to suppliers outside the UK. This also means security of supply is not guaranteed. Can improvements be made to the use of these energy sources?A key environmental problem is that fossil fuel combustion releases fossil CO2 to the atmosphere. This is now, beyond reasonable doubt, linked to global warming and climate change. Atmospheric CO2 also dissolves in ocean water, forcing an increased acidity greater than any time in the past 20 Million years. Even those who still do not believe in climate change cannot escape the inevitability of ocean acidification / with as yet un-predicted consequences. For this reason alone, atmospheric CO2 must be reduced.To enable continued use of fossil fuels, whilst renewable sources are developed, it is an urgent requirement to de-carbonise their combustion. The Stern Review of Climate Change Economics in 2006 clearly re-stated that significant progress must be made during the ten years until 2017.This research proposition addresses the fossil fuel issues in two ways: Firstly, to create a UK Centre of university expertise in the capture of CO2 from power plant. Current industrial systems rely on chemical absorption by solvents, but require a very high energy input, which reduces the environmental gain. The Centre will focus on new technologies of CO2 separation by adsorption onto nanoporous materials materials, by filtration of CO2 from power plant flue gases by newly created semi-permeable membranes, and by membrane separation of oxygen from air, to enable oxy-fuel combustion and efficient CO2 separation.Secondly, we acknowledge that there is, and will be, a need to remove existing CO2 emissions from the atmosphere. The reductions proposed from power plant emissions do not reduce existing CO2, they just make the increase slower. To control the earth atmosphere and produce a sustainable climate requires extraction of CO2 already emitted. This is routinely achieved, at low cost, by vegetation. We will create an entirely new centre of university expertise which will focus on using bio-mass from agriculture, forestry and waste. This can firstly make bio-fuel to replace fossil sources, and the residues can be pyrolised to form charcoal. Such charcoal has been used in traditional cultures to enhance soil fertility, and locks up carbon for thousands of years. Improvements in land use in the EU, USA, and developing world can achieve this, by an integration of engineering, soil science, and social benefit to cultivators.The University of Edinburgh and Heriot-Watt University already host the UK's largest academic centre investigating the geological burial of CO2 captured from power plant. There are existing multi-skilled networks in Edinburgh linking land use, agriculture, social, legal and economic analysis, chemical engineering and petroleum geoscience. Creation of the Carbon Capture Centre will be an ideal complementary activity, and the range of expertise, from atmospheric capture, to power-plant capture to cultivation and geological burial will be unique.Outputs from the Centre can help the UK to combust coal and gas with environmentally clean methods, to enhance energy security by diversifying away from fossil fuel sources, and to commence the direct clean-up of CO2 from the atmosphere in a energy efficient, and financially efficient, sustainable way.
 
Description This project is part of a larger collaborative venture with University of Edinburgh, for a research programme into technology supporting carbon dioxide capture from power stations. The Scottish Funding Council provided additional funds used to establish a new laboratory facility to support the staff employed. At Heriot-Watt, Dr Humphrey Yiu was appointed and established a facility to develop and test novel materials for CO2 capture. These materials are based on naturally occurring ones which would reduce the environmental burden should their potential for capturing CO2 prove feasible. We appointed two PhD students to support Dr Yiu; one looking at novel inorganic-organic hybrid nanoporous silica for chemisorptions of carbon dioxide. This material has an amine group which was shown to enhance the CO2 adsorption capability. The second student worked on a natural polymer. By depositing chitosan, a waste biopolymer, onto a fume silica support, a composite material was formed with a surface area over 100 m2/g. Moreover, this chitosan-silica composite material shows a CO2 adsorption capacity of 10 - 15 cm3/g (273K, 1 bar). Considering these composite materials having a much lower carbon footprint than most state-of-the-art sorption materials for carbon capture, such as metal-organic frameworks (MOFs), such adsorption capacity value is remarkable and potentially valuable for future work. The student is still completing his studies and further outputs are expected.
In parallel with the chemical adsorbents, we appointed a 3rd PhD student to work on novel methods for combustion. Chemical looping combustion (CLC) is potentially one of the technologies best suited for capturing CO2 at low cost and efficiently providing a low energy option for the separation of CO2 from flue gases. The process consists in the cyclic reduction and oxidation of metal particles which act as oxygen carriers. These metal particles are exchanged between two reactors, usually a circulating fluidised bed and a bubbling bed reactor, where the oxidation and reduction reactions occur, respectively. In certain countries, this technology is already at pilot plant scale and further optimisation is needed before it can be commercially viable. Our work was focused on providing this optimisation by developing detailed models of the combustion system, integrated into a model of the power plant itself. The model contains the hydrodynamic characterisation of the oxidation reactor involving optimal circulation rates, thermal output, residence time; the full characterisation of the combustion involving bed expansion, residence time, bubble characteristics; a complete mathematical model for the hydrodynamics and the heat and mass transfer in the two reactors; the economic analysis and process integration of the full system. So far the results obtained are aimed at exploring the feasibility of the plant layout by using ASPEN
A further study was conducted in collaboration with colleagues at University of Edinburgh. Dr Chiara Maria Ferrara was appointed to work on membrane separation methods for CO2 capture. Dr Ferrara has a strong background in modelling gas separation properties of membranes and has established an experimental facility to test these membranes.
The PhD students appointed on this grant have now completed their work and graduated.
Exploitation Route Publications from the funded work continue to appear; both PhD students have completed their studies and one will graduate in July 2016. We have used the expertise gained through the project to collaborate with other groups and have applied for further funding in CO2 capture and utilization area.
Sectors Chemicals,Energy,Environment,Manufacturing, including Industrial Biotechology

 
Description The grant finished in August 2014 and the research team has continued to publish its findings. One of the researchers, R.Porrazzo has published several articles in FUEL, with the most recent in Jan 2016. He has also completed his PhD thesis, and graduated in July 2016. The work we have covered with the funding has generated other collaborations and applications for further funding in the related area. The second research student funded under this grant, Mr G Sneddon, submitted his thesis and graduated in July 2017 with a PhD in Chemical Engineering. The PI (G.White) is now a CI for a new funded grant for solid adsorbents for industrial CO2 capture (EP/N024540/1).
Sector Energy
 
Description Adsorption Materials and Processes for Carbon Capture from Gas-Fired Power Plants - AMPGas
Amount £1,111,261 (GBP)
Funding ID EP/J02077X/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Academic/University
Country United Kingdom
Start 09/2012 
End 08/2015
 
Description Catalytic Utilisation of CO2 for Drug Precursor Synthesis - A New Direction for Carbon Capture and Storage
Amount £14,217 (GBP)
Organisation The Royal Society 
Sector Academic/University
Country United Kingdom
Start 03/2014 
End 02/2015
 
Description Novel adsorbents applied to integrated energy-efficient industrial CO2 capture
Amount £985,463 (GBP)
Funding ID EP/N024540/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Academic/University
Country United Kingdom
Start 07/2016 
End 06/2019
 
Description Step Change Innovation in Carbon Capture: Low Energy Enzymatic Processing
Amount £62,680 (GBP)
Organisation Scottish Carbon Capture and Storage 
Sector Private
Country United Kingdom
Start 07/2013 
End 12/2015
 
Description Nanocharacterisation for materials with Kelvin Nanocharacterisation Centre (KNC) at University of Glasgow 
Organisation University of Glasgow
Department Physics and Astronomy Department
Country United Kingdom 
Sector Academic/University 
PI Contribution We have developed nanomaterials (nanoporous materials and nanoparticles), which are of the research interest of KNC.
Collaborator Contribution KNC provides state-of-the-art TEM and STEM facilities for the characterisation of nanomaterials with expertise in operating advanced instruments and results interpretation.
Impact publications are in preparation.
Start Year 2013