Extending CO2 Transport Solution (ECOTS)
Project partnersEquinor Energy AS (Project owner), Total E&P Norge AS, Gassco, LedaFlow Technologies DA, Schlumberger Information Solution AS, Shell Global Solutions international
Project period05/20 – 09/21
Background and project purpose ?
Carbon capture and storage (CCS) is one of the key technologies for achieving Norway's and Equinor's climate targets and establishing hydrogen value chains. The existing carbon capture and storage projects are based on storage in hydrostatic-pressurized saline aquifers. The transport solution in pipeline is liquid CO2, which does not have any technology gap for Flow Assurance.
Two-phase flow of CO2 is possible under certain conditions, i.e. injection into depleted or low pressure reservoirs. A solution based on transport by pipeline with two-phase flow will enable a more flexible design and a larger operational window. A qualified Flow Assurance tool is critical for optimizing design and safe operation with two-phase flow of CO2.
The systematic assessment of existing Flow Assurance tools indicates technology gaps in basic models for hydrodynamic and transient processes. Significant progress has been made in the ongoing project 618052 CO2FACT JIP. The project confirms the possibility of further developing existing Flow Assurance tools for two-phase CO2 flow. It is absolutely necessary to validate tools against data from large-scale test facilities such as Equinor’s flow loop in Porsgrunn, Norway, or operational data from fields with two-phase flow in transport pipeline. There is little chance of such operational data becoming available in the near future. Experimental data from projects such as CLIMIT-Demo project 617096 CARDICE JIP can only be used for the study of pressure relief processes.
What was the project objective?
The project has three main objectives:
• Upgrade the multiphase rig in Porsgrunn for CO2 applications.
• Execute experimental campaign for CO2 pipeline flow: Steady-state and transient two-phase gas-liquid flow in a pipe close to horizontal inclinations
• Assess the scaling performance of the existing Flow Assurance tools and quantify the uncertainties of these tools
What has the project done in terms of activities?
Four different activities were planned, and three of them have been completed by June, 2021.
• Mechanical work to upgrade Equinor multiphase rig to CO2 was completed in Sept.2020;.
• Commissioning tests of the multiphase flow rig were carried out in Oct.2020;
• CO2 two-phase experiments with five different types of flow were completed in April, 2021:
o Ready for operation (RFO): Displacement of N2 by CO2
o Steady-state two-phase flow
o Two-phase flow tests with slugging potential
o Controlled depressurization
o Flow via valves
o Impact of impurities
The fourth activity is the assessment of commercial Flow Assurance tools by comparison with the available experimental data (CO2FACT JIP, CARDICE JIP and results from ECOTS). The assessment with CARDICE JIP data was completed.
What has the project achieved? Did the project achieve its objective?
The following achievements have been obtained:
• All laboratory activities were executed according to the plan, and no HSE incident occurred.
• The test facility is functional as expected, extensive operational experiences on CO2 fluid were obtained;
• All tests planned were executed as planned, and a huge amount of experimental data of high quality were obtained;
The remaining activities are:
• Documentation of the experimental results;
• Analysis of the experimental results;
• Assessment of the commercial Flow Assurance tools;
The project is still on-going, and the remaining activities will be executed in the second half of 2021. A huge amount of experimental results has been collected, these results are valuable also to process simulator, safety assessment under CO2 leakage, etc. The assessment of the Flow Assurance tools in this project does not cover any improvement of the software. It is believed that additional activities are needed to close the technology gap of the existing Flow Assurance tools for CO2 two-phase applications. The experimental data obtained from this project will be a crucial input to the future improvement activities.
Shell Global solutions Internationals joined project in 2021.