Hydrodynamics and metering of two-phase (liquid/dense gas) flow for carbon capture and storage
Funder
UKRI - EPSRC
Project team
Total Value of Project
£476,809
Duration
01/01/25 - 31/01/28
Project overview
Carbon capture and storage (CCS) is a global strategy considered essential to mitigate climate change. The technical challenges for Brazil are severe, where the pre-salt is a complex of carbonate reservoirs in ultra-deep waters, under a thick layer of salt. Oil production from pre-salt reservoirs contains large volumes of gas, primarily natural gas and CO2. Simultaneously, CO2 is geologically sequestered in the pre-salt reservoirs, thereby performing enhanced oil recovery (EOR), while also delivering CCS in pursuit of Net Zero.
Accurate metering of such fluids is a long-standing technical challenge, due to their complex composition and behaviour. Physical properties (such as pressure, temperature, viscosity, salinity, and density) can vary widely, both geographically and over time. A range of multiphase flow metering technologies have been developed to provide measurements of these difficult fluids. Newer reservoirs typically offer greater technical challenges, such as higher pressures, higher CO2 content and higher viscosities.
CCS requires traceable metering of fluids (typically CO2, alongside other material) injected into depleted reservoirs. Such flows are often complex, multiphase, and sensitive to parameter variations.
Much effort has been devoted to developing high fidelity models for engineering applications such as multiphase flows, but significant uncertainty remains. Given their large economic and environmental importance, improving confidence in these models is not simply a matter of pursuing higher fidelity, but of decreasing uncertainty for economically and environmentally significant decision-making. In multiphase flow, the mathematical models used to predict flow patterns are typically developed and calibrated using datasets unrepresentative of future production conditions, being derived either from laboratory scale flows at low pressures, or from field data, but under conventional, less challenging, production conditions.
The accurate prediction of two-phase flow patterns is essential for the calculation of physical quantities such as head loss and heat and mass transfer coefficients, as well as for the prediction of vibrational modes in fluid-structure interaction problems. Traditional calculation methods based on fluid mechanics models, such as the two-fluid model, are limited, particularly when applied to Brazilian pre-salt conditions entailing complexities such as high pressures and high volumetric fraction of CO2.
Accordingly, a new experimental rig has been designed and built at the University of São Paulo, Brazil (USP), to generate data for dense gas/liquid mixtures. Initial results (for horizontal inclination only) indicate that dense-gas/liquid flows have important features that are not predicted by current models in the literature.
The project will explore the use of a high density gas to simulate high gas/oil density ratios while under low experimental pressures (at reduced energy cost and risk). The experimental investigation will use sulphur hexafluoride (SF6) to simulate hydrodynamic conditions typical of the Brazilian pre-salt reservoirs for flows of oil and CO2 in the supercritical state in order to develop thermodynamic models as well as flow metering technology to operate under the equivalent high pressure conditions.
Project objectives
- Modelling, and visualisation of high pressure multiphase flow with low pressure SF6 as an experimental substitute for high pressure CO2.
- Data collection, treatment and analysis of physics-informed machine learning algorithms for the prediction of flow patterns and hydrodynamic transients.
- Coriolis meter prototype development to perform multiphase flow metering under simulated high pressure conditions.
- Compare modelling and flow meter performance with actual high pressure flows, with experiments at NEL’s Advanced Multiphase Facility at elevated pressures using equivalent gas densities and flow rates to USP trials.
Impact statement
The project will provide scientific and technological advances to support the development of the high pressure Brazilian pre-salt reservoirs as CCUS storage sites by:
- Evaluating the use of SF6 as a low-cost, low risk simulant of high pressure gas/liquid mixtures;
- Developing models of multiphase flow behaviour for high pressure environments, informing fluid science and reservoir modelling.
Develop and demonstrate flow metering techniques for high pressure applications such as Brazil pre-salt CCUS.
Outputs
- Conference presentations
- Journal papers
- Possible patent filings of new flow metering technique
- Laboratory experiments demonstrating high pressure behaviour
- Laboratory experiments demonstrating flow meter performance
