Partners are being sought for a project to study the impact of removing brine from under-sea stores that could house captured carbon.
The call from the Energy Technologies Institute follows a previous ETI project in its Carbon Capture and Storage (CCS) technology programme that led to CO2 Stored, the UK’s principal storage screening database.
The database is said to have made a number of assumptions to estimate capacity and injectivity for each of the identified 550 stores off the UK’s coast. One of these was that brine was not produced from the reservoir store before, during or after CO2 injection.
According to ETI, if a reservoir store is pressurising as a result of CO2 injection, brine can potentially be removed through a purpose built well or wells from the store to depressurise it whilst still retaining the operation and integrity of the store.
The brine could potentially be sent to another aquifer or disposed of in the sea. Brine production is a recognised way of controlling the reservoir store pressure and potentially its flow, and its use is a contingency in several store designs.
Recent work published by Heriot Watt University showed that producing brine in the United Kingdom Continental Shelf (UKCS) may be beneficial to injection rates and storage.
This project will produce a cost-benefit analysis of brine production, using the CO2Stored database and models developed in the ETI’s UK Storage Appraisal Project as a starting point. Analysis will cover saline aquifers and oil and gas reservoirs.
The first stage of the project will examine any changes in injectivity and storage capacity as a result of producing brine, the additional cost of using brine wells, and the savings realised, if any.
ETI say that if the first stage shows there are potential benefits, these will then be refined and the operational implications examined further.
Paul Winstanley, ETI CCS project manager said: “The ETI’s analysis of the UK energy system highlights the importance of CCS to an affordable, secure and sustainable low carbon energy system.
“This project will build on our earlier work and help to build the evidence base, increase knowledge and understanding about the potential stores we have identified and build confidence among potential operators and investors.”
The request for proposals will close on 24 September 2015. The deadline for notification of intention to submit a proposal is 10 September 2015. The request for proposals can be viewed at: http://www.eti.co.uk/category/proposals/