IORSim - an add on tool to ECLIPSE for simulating IOR processes Sodium Silicate gelation and reservoir flow modification

Transcription

1 IORSim - an add on tool to ECLIPSE for simulating IOR processes Sodium Silicate gelation and reservoir flow modification

2 Mature fields Chemical EOR Challenges Temp. gradients Complex flow pattern Multiple Wells Geochemistry Oil Displacement Water Chemistry

3 Eclipse Reservoir simulator The Approach Restart Files Sw, Po, Pw, qw IORSim (*) advect components Geochemistry Oil Rate Mg Water Rate SO4

4 Combine multiphase models with chemistry - interpret & upscale lab experiments IORCoreSim (DOUCS) Geochemistry Polymer, Silicate Surfactant Pore scale (LB & DPD) IORSim Geochemistry ECLIPSE, OPM, + Polymer, Silicate MEOR Surfactant MEOR? Nanoparticles?

5 Results IOR Norway 2015 Simulated Pore Water Produced water composition Chemistry INJ I Mg ions INJ II PRD I INJ III Reservoir ph SO4 Model Temp Gradients SO4 Model Constant Temp

6 IORSim Backward Coupling Run Eclipse Δt Stop Eclipse process Run IORSim Δt, calc X Update SATNUM Predefined rel perm curves SATNUM tells ECLIPSE which rel perm curve to use X = EOR response, e.g.: Low sal reduce Sor Silicate reduce Perm

7 Sodium Silicate Chemistry Gelation time gelation 5wt% Sodium Silicate Na 2 O:(SiO 2 ) n + HCl Oligomeric silicic acid Phase separation Nano sized Block 2μm aggregation A. Stavland, H. Jonsbråten, O. Vikane, K. Skrettingland and H. Fischer, In-depth Water Diversion Using Sodium Silicate Preparation for Single Well Field Pilot on Snorre, 16th European Symposium on Improved Oil Recovery Cambridge, UK, April Sebastian Wilhelm and Matthias Kind, Polymers 2015, 7, ; doi: /polym

8 wt%hcl Lab Results Temp A. Stavland, H. Jonsbråten, O. Vikane, K. Skrettingland and H. Fischer, Indepth Water Diversion Using Sodium Silicate Preparation for Single Well Field Pilot on Snorre, 16th European Symposium on Improved Oil Recovery Cambridge, UK, April 2011 Silicate concentration [wt%] t gel = ζe α[si] e β[hcl] e γ [Ca] e E a/rt

9 How to use t gel in IORsim? Need to Capture basic features: 1. Temperature, Si, Ca, HCl effect on gel time 2. Formation of nano (not pore blocking silicate) particles

10 Sodium Silicate Gel Formation Model Rate of Si loss equal to gel formation: o dc Si dt o 0 c gel 1 C Si = dc gel dt n = kc Si C 1 t n dc gel = C0 n dc Si = gel 0 k dt, C Si Rate const. fit to data Concentration of Pore blocking silica o t gel = 1 k 1 n C 0 1 n C gel C 0 C 0 1 n 1

11 Fit to t gel obtained from Lab Data 100 Norm Gel Time t_gel[model] t_gel[lab] n = 4 C gel = 0.3wt% k = 10 2 ζe β[hcl] e γ [Ca] e E a/rt wt% silica

12 4 aqueous species + 1 mineral phase 1. Silica 2. HCl 3. Mobile Gel 4. Calcium 5. Immobile Gel Sodium Silicate Activator Nano size gel particles Divalent ions Rigid gel

13 Permeability modification Gel formation increases specific surface area: S t = S 0 + YS ImGel k = φ 2τS 2 k k 0 = 1 + Y 2τk 0 φ 0 If Y = 1wt%: wt% Immobile gel r μ 1 k 0 1D k 0 k 4 but k 0 10mD k 0 k Nano sized gel particles in aggregates r μ 10nm

14 The Snurre Field History Discovered in 1983 Reservoir Temperature 90C Water injection started in 1992 Water Breakthrough Summer 1992 Silicate injection April-May 1993

15 producer View from top Snurre Permeability View from the side injector 4000mD 100mD 240x30x7 = blocks

16 Temp View from top Temp View from side Water Saturation View from top Water saturatio View from side

17 Temp View from top Temp View from side Water Saturation View from top Water saturatio View from side

18 Temp View from top Temp View from side Water Saturation View from top Water saturatio View from side

19 Temp View from top Temp View from side Water Saturation View from top Water saturatio View from side

20 Production & Pressure without treatment Injector Producer BHP Water Rate BHP

21 5wt% Silca injection for 65 days Silicate wt% Calcium wt%

22 Permeability reduction Perm reduction View from top Perm Reduction View from side

23 Perm reduction View from top Perm Reduction View from side

24 Perm reduction View from top Perm Reduction View from side

25 Perm reduction View from top Perm Reduction View from side

26 Perm reduction View from top Perm Reduction View from side

27 Perm reduction View from top Perm Reduction View from side

28 producer Water Saturation Profile injector

29 producer Water Saturation Profile injector

30 producer Water Saturation Profile injector

31 producer Water Saturation Profile injector

32 producer Water Saturation Profile injector

33 producer Water Saturation Profile injector

34 producer Water Saturation Profile injector

35 producer Water Saturation Profile injector

36 producer Water Saturation Profile injector

37 producer Water Saturation Profile injector

38 Production & Pressure data with treatment Injector Producer BHP Oil Rate Water Rate BHP Water Rate

39 Increased recovery and reduced water cut Additional Oil Reduced Water Prod

40 Effect of grid size 240x30x7 cells 60x15x7 cells

41 Remarks ECLIPSE is slow compared to IORSim For design: Run ECLIPSE once Use IORSim without backward coupling to design optimal slug then run full simulation Grid resolution vital for design Necessary to have local grid refinement in IORSim Silicate model not complete Not fully taken into account salt effects Effect of mineral dissolution/precipitation and ph Filtration model silica gel particles

42 Conclusions IORSim and ECLIPSE coupling works well The full potential in this technology is to apply to realistic field cases Simulation grid could have a huge impact on the EOR effect