Deploying Nanotechnology in Oil and Gas Operations: Pore-Scale Modelling of Nanoparticle Adsorption-Desorption Behavior Boya Subhono, Mark Wilson, Nik Kapur, Anne Neville, Harvey Thompson University of Leeds, UK
PRESENTATION TOPICS Company Overview (2-3 minutes); Problem Description; Methodology; Conclusion; Future work
Institute of Engineering Thermofluids, Surfaces & Interfaces (ietsi) Largest insitute within the School of Mechanical Engineering at University of Leeds Top rated under UK Government Research Assessments Core strengths in Corrosion and erosion-corrosion Mineral scale management Combustion Tribology CFD Optimization Metrology
ietsi Corrosion and Erosion-Corrosion Corrosion Electrochemical assessment Corrosion in oil and gas (sweet and sour) Marine corrosion Evaluation of pitting and other localised corrosion Stainless steels, Cu-based alloys, CRAs Erosion-corrosion Erosion-corrosion assessment Erosion-corrosion modelling Cavitation-corrosion Mitigation using chemicals Coating development and assessment Assessment of damage mechanisms on composite coatings Development of new HVOF coatings
ietsi Mineral scaling Surface deposition Kinetics and mechanisms of surface deposition and adhesion Adhesion assessment by fluid flow analysis Calcium carbonate and barium sulphate Wide Angle X-Ray Diffraction (WAXRD) Tube blocking tests with online sensing In situ measurement of crystal formation (Brookhaven, US) Anti-fouling surfaces Assessment of surfaces for low fouling Surface modification by chemical and physical means
ietsi Advanced Coatings Design Lab State-of-the-art commercial scale PVD system Application-driven research approach Synergy with tribology and surfaces/interfaces research
ietsi Extensive surface analysis capability μm 50 25 1.8 mm 2.3 mm 0
ietsi Oil and Gas Education MSc Oilfield Corrosion Engineering Tailored MSc for the oil & gas industry Provides students with skills needed to practise as Corrosion Engineers in the oil & gas sector Led by Professor Anne Neville Modules include Corrosion Mettalurgy & Welding Surface Engineering Corrosion Inhibition Corrosion Monitoring Corrosion Prediction Flow-induced Corrosion Coatings, linings & non-metallics Risk Assessment Erosion-Corrosion
NANOTECHNOLOGY IN OIL AND GAS Rapidly growing interest in nanotechnology in oil and gas industry, as highlighted by recent SPE conference Example applications include using nanoparticles for Agents for modifying surface wettability Mobilization agents for recovery of residual oil Enhancing mineral scale management systems Enhanced drilling fluids Water shut-off
NANOPARTICLE TRANSPORT Problem in using nanoparticles downhole is understanding and controlling nanoparticle transport through porous media Nanoparticles need to be delivered to the required location Nanoparticles need to adsorb/desorb to/from surfaces of they are to change surface properties e.g. wettability effect of flow?
NANOPARTICLE TRANSPORT Experimental corefloods can give some idea of macroscopic effects and changes in behavior, but give no indication of pore-level coverage or mechanisms Inject e.g. nanoparticle suspension Rock core sample Monitor effluent What is the distribution and coverage inside?
NANOPARTICLE TRANSPORT Pore-scale CFD can help explore nanoparticle transport and adsorption and desorption
AIM & METHODOLOGY Aim is to explore the effect of flow on adsorption Consider flows in idealized pore-scale geometries Finite element analysis Build up understanding of influence of flow and geometry on adsorption and desorption Infer behavior in much larger pore networks
MODEL Treat nanoparticle suspension as a dilute suspension with a continuous concentration field Navier-Stokes equations for (steady) fluid flow One-way coupling of (time-dependent) advectiondiffusion equation for nanofluid concentration Freundlich adsorption-desorption model
GEOMETRY CONSIDERED To isolate effect of inclination of surface to main flow direction, consider: Flow direction 45ᵒ 90ᵒ 135ᵒ α 0 ᵒ 180 ᵒ Flow Active adsorption surfaces 90 ᵒ 0 ᵒ 180 ᵒ
GOVERNING EQUATIONS AND BOUNDARY CONDITIONS Bulk concentration Surface concentration of adsorbed species
GOVERNING EQUATIONS AND BOUNDARY CONDITIONS
SIMULATION CONDITIONS Description Value Unit Initial concentration in place 0 mol/m3 Inlet discharge concentration 1000 mol/m3 Adsorption rate constant 1.00E-06 m3/(s.mol) Desorption rate constant 1.00E-09 1/s Water Diffusivity 1.60E-09 m2/s Channel width 1.00E-05 m Simulation time length 2.00E+03 s Particle diameter 1.20E-09 m Inlet pressure 3 Pa Outlet pressure 0 Pa
RESULTS Velocity field
RESULTS Concentration field at steady state
Bulk concentration at the active surface RESULTS Higher concentration at the edge that is perpendicular to and facing the flow Arc length around octagon
Reduction in concentration of adsorbed species compared to surface facing flow RESULTS time
CONCLUSIONS CFD offers the opportunity to explore nanoparticle penetration and distribution within pore networks To begin, simple geometries considered to explore local effects Through variations in the bulk concentration at the surface, fluid flow has been shown to influence the local adsorption of nanoparticles However, flow is not explicitly included in the material balance (adsorption-desorption) equation
FUTURE WORK Adsorption experiments using micromodels to verify the correct adsorption-desorption model to be used Extension to more complicated pore networks Extension to 3D
ACKNOWLEDGEMENTS This work was supported by the Flow Assurance and Scale Team (FAST) Joint Industry Project Thank you for your attention