Introduction

1. Anglo-French Scientific Discussion Seminar

2. Transport of CO2 for Carbon Capture and Storage in the UKMartin Downie, Julia Race and Patricia SeevamSchool of Marine Science & TechnologyNewcastle University Anglo-French Scientific Discussion Seminar

3. Introduction The presentation is based on the premise that: • Technically viable capture technologies are available • Sufficient safe ‘acceptable’ storage sites exist to accommodate ‘target’ quantities of CO2 • Legal and regulatory instruments allowing CCTS have been developed • An economic framework has been put in place so that industry will engage with CCTS What are the technical challenges required to develop a CO2 transport infrastructure for the UK connecting multiple sources to offshore sinks ?

4. Current Status of CO2 Transport It can be argued that CO2 transport has a low profile in the UK because it is widely believed: • CO2 transport is a specialised but well established technology. Within North America there are over 3000 km of pipeline dedicated to the transport of 45 million tonnes of dense phase carbon dioxide annually, mostly for EOR. • in the UK there is an extensive existing infrastructure that could be used for transporting CO2 from capture to subsea storage sites. That is, the technology is proven and requires no further research, and a large proportion of the infrastructure is already in place

5. USA and UK CO2 Transport • CO2 transport in the USA is concerned with purpose designed ‘natural’ CO2 pipelines running overland through relatively sparsely populated regions largely for EOR • UK requirements are for an infrastructure to transport anthropogenic ‘impure’ CO2 from multiple sources overland through densely populated regions to subsea storage sites using existing infrastructure where it is technically viable and generally advantageous. • In the USA there is a legal framework for the design, operation and maintenance of dense phase CO2 pipelines. • Differences in CO2 composition has major implications for pipeline design procedures and practice, and for the legislation required to bring it about in the UK

6. CO2 Properties • Can exist as solid, liquid or gas • Dense phase: density of a liquid, viscosity of a gas • Properties are sensitive to impurities which can shift the supercritical point, and open up a two phase envelope • Impurities change the density, compressibility, and H2O solubility • CO2 is a hazardous gas that can become significantly more toxic by the presence of impurities

7. Pipeline transport • Low pressure CO2 gas pipelines are of the order of 20 times more expensive than a high pressure dense phase pipeline • CO2 transported in dense phase, the hydraulic flow being dictated by the conditions at the injection site. • The pressure and temperature have to be maintained at sufficiently high levels to maintain dense phase, where necessary using booster stations. The hydraulics is sensitive to the composition of the mixture. • The composition is dictated by the manner and cost of capture/ purification, material constraints of pipelines and environmental considerations applying at the sink. • Quality of CO2 specified according to purpose. EOR specification may be more rigorous than for storage • High pressures required at delivery point for injection

8. Areas of uncertainty Source: www.wikipedia.com Pipeflow: • Equations of state for dense phase CO2 with impurities, models and validation • Transient flow behaviour Material properties: • Toughness to prevent fracture propagation • Corrosion, H20 solubility level • Non-metallic materials, elastomers etc Risk analysis • Leakage and dispersion studies • Consequence and frequency quantification • Regulation • Classification of dense phase CO2, Design Codes.

9. Large scale infrastructure • The total CO2 emissions from all reporting UK industrial sites was 283Mt in 2004 • Most of the major sources are power plants, steel plants and petrochemical complexes • The 20 largest power plants represent 49% of the total industrial emissions. • It has been estimated that there is sufficient CO2 storage capacity in the UKCS oil and gas fields to store all current UK industrial emissions for between 13 and 38 years. Source: Report No COAL R308 DTI/PUB URN 06/2027

10. Existing Infrastructure Onshore: generally in use, or non-existent Offshore: • Over 11000km oil and pipelines laid in UKCS in last 40 years. Investment of £300M/yr. • Potential lifetime of 100s of years • Only a small part of infrastructure suitable for re-use • Northern & Central fields: fewer pipelines, long distances, critical trunk lines for many years to come • Oil & gas fields with direct access to shore plants desirable • EOR vs Storage • Decommissioning vs re-use

11. Infrastructure Development Hare,spe108931, Offshore Europe 2007 • Probable initial development will be storage in Southern North Sea • Risk averse strategy would concentrate on gas fields, cost averse on storage closest to terminals including saline aquifers • Fundamental issue governing re-use is safe delivery of supercritical CO2 which determines pipeline capacity • Total existing pipeline capacity varies from terminal to terminal

12. Integrated CO2 pipeline network • No experience of transporting CO2 for long distances offshore. The only subsea CO2 pipeline is the Snohvit pipeline • Pressures typically 100 bar or above for existing offshore pipelines. Maintaining sufficiently high pressures for delivery specifications could be a problem • Availability of existing infrastructure • Upgrading existing infrastructure for EOR • Pipeline integrity and fitness for purpose in re-use • Large scale network analysis and optimisation required

13. Conclusions • Strategic studies and planning are required for a large scale CO2 transportation scheme, how much, when and where? • The UK experience will be different from that of the USA, and technical issues specific to the UK remain to be resolved • Regulations and standards appropriate for UK required • Leadin time for planning and construction of pipelines is of the order of years • Time is running out!