WP1.3 Transient fluid dynamics of CO 2 mixtures in pipelines

Transcription

1 WP1.3 Transient fluid dynamics of CO 2 mixtures in pipelines Sintef Energy Research (Norway), TNO (Netherland), CSM (Italia) Workshop EC FP7 Projects: Leading the way in CCS implementation London, April 2014 Alexandre Morin, 1

2 The work package Transient fluid dynamics of CO 2 mixtures in pipelines Assess the influence of impurities in CO 2 in pipeline transport Benchmarking of existing tools available to the consortium Contribute to SP2 by giving results Techno-economic analysis Risk assessment

3 Many natural gas pipelines why start over with CO 2? Stronger cooling with CO 2 Higher pressure during depressurisation Natural gas phase diagram CO 2 phase diagram From wikimedia commons

4 Challenges related to CO 2 transport Behaviour during transients Depressurisation of a pipe Pressure evolution Predict the lowest temperature Crack propagation Not in IMPACTS SINTEF Materials and chemistry 4

5 Challenges in numerical modelling Mixture with "overwhelmingly" CO 2 Close to single component Thin phase envelope in pressure/temperature From wikimedia commons Liquid-gas Single phase 5

6 Challenges in numerical modelling OLGA generally solves the equations in Pressure/Temperature Instabilities with mixtures containing one overwhelming component Solved for pure CO 2 with the single-component module New OLGA model solves the equations in Pressure/Enthalpy Not available yet Expected to work better on CO 2 mixtures with impurities We solve the equations in Density/Energy Natural variables for the fluid-dynamical equations Thermodynamic routines non-standard From wikimedia commons 6

7 Fluid-dynamical model Single-phase compressible flow equations (Euler equations) Mass conservation Momentum conservation + + = 0 ρρ v + p = 0 Total energy conservation ρ e + v2 2 + ρ e + v2 2 v + pp = 0 Multiphase flow model Two sets of the three conservation equations Advection of volume fraction α k Seven equations In the phases gas α g p g, T g, μ g, v g p g, T g, μ g, v g p l, T l, μ l, v l liquid p l, T l, μ l, v l 7

8 Fluid-dynamical model Play on relaxation and instantaneous equilibrium Two-fluid: Two independent phases Drift-flux: Mixture seen as one complex phase TF 4 /DF 3 necessary to use an equilibrium equation of state Are the underlying assumptions reasonable? 8

9 Fluid-dynamic model Slow transients Time scales of flow larger than equilibrium time scale 0 C Faster transients Time scales of equilibrium relevant to the problem dynamics Equilibrium kinetics impacts the speed of sound Not satisfying to force equilibrium? Define how to be outside of equilibrium Not a thermodynamic problem: caused by the averaging T > 0 C Water with ice cube 0 C T > 0 C Averaged 9

10 Implementation of thermodynamic routines Ruhr University Bochum (Prof. Roland Span) Accurate equation of state for combustion gases Thermodynamic interface between fluid-dynamics and thermodynamics Flash routines Density/Energy 10

11 Status of work SINTEF general-purpose thermodynamics library interfaced with RUB's library Use EOSCG with our general equilibrium calculation routines Development of energy/density flash algorithms Strong focus on robustness Efficiency increased by parallelisation The following impurities have been successfully tested so far (as binary mixture with CO 2 ): N 2 CO Ar O 2 11

12 Benchmark study Benchmark study Focus on transient/accidental situation Report describing the benchmark cases Different pipe geometries Compositions based on results of IMPACTS workshop The cases will highlight the strengths of the different codes Pipe geometries CO 2 N 2 O 2 Ar NO x SO x CO H 2 S H 2 CH 4 C 2 + NH 3 Amine Pure CO 2 100% Coal-fired power plant Amine-based absorption Coal-fired power plant Selexol-based absorption Natural gas processing Amine-based absorption 99% 2000ppm 200ppm 100ppm 50ppm 10ppm 10ppm 1ppm 1ppm 98% 6000ppm 1ppm 500ppm 400ppm 100ppm 1% 1000ppm 95% 5000ppm 200ppm 4% 5000ppm

13 Benchmark study Vapour film Type of code OLGA and SINTEF in-house code: 1D Fluent (CSM): 3D Results very dependent on submodels Heat transfer Friction Equilibrium Heat transfer Critical flux Film boiling Onset of nucleate boiling Wall temperature Gas Depressurisation P aaa v ooo < c sssss Liquid P iiii

14 Link to experimental data CO 2 transport rig, CIUDEN, Spain Possibility to depressurise it to atmosphere Impurities in CO 2 CO 2 transport rig, CIUDEN, Spain 14

15 Why is it important for IMPACTS Steel qualities have design minimum temperatures Lowest temperature to be expected Qualify or disqualify a steel quality Pipeline design must take the transient events into account Minimum acceptable pipe thickness Impacts the amount of steel Effect on the cost of pipeline Input model for atmospheric dispersion models

16 Thank you for your attention Nils A Røkke, Chairman of the Executive Board, Nils.A.Rokke@sintef.no Mona J. Mølnvik, Coordinator, Mona.J.Molnvik@sintef.no Astrid Lilliestråle, Project manager, Astrid.Lilliestrale@sintef.no An Hilmo, Project secretary, An.Hilmo@sintef.no Website: Acknowledgement: The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7-ENERGY STAGE) under grant agreement n (The IMPACTS project). The authors acknowledge the project partners and the following funding partners for their contributions: Statoil Petroleum AS, Lundin Norway AS, Gas Natural Fenosa, MAN Diesel & Turbo SE and Vattenfall AB. 16