Mohsen Tagavifar - CPGEcpge.utexas.edu/sites/default/files/research... · Mohsen Tagavifar Shayan...
Transcript of Mohsen Tagavifar - CPGEcpge.utexas.edu/sites/default/files/research... · Mohsen Tagavifar Shayan...
Microemulsion Viscosity and its Implications for Chemical EOR : Experimental Results and a Model
Mohsen Tagavifar
Research Showcase in Petroleum and Geosystems Engineering • September 8, 2015
Research Showcase Sponsored by
Chemical EOR Project Sponsors
Chemical EOR Research Team Faculty and Senior Research Scientists Matthew Balhoff Mojdeh Delshad Chun Huh
Mark McClure Thomas Milner Kishore Mohanty
Quoc Nguyen Gary Pope
Kamy Sepehrnoori Upali Weerasooriya
Administrative Staff Esther Barrientes Joanna Castillo
Scientific Consultant Eric de Rouffignac
Technical Staff Arnob Bhuyan Eric Dao Sophie Dufour Gayani Kennedy
Austin Lim Jith Liyanage Jun Lu Chammi Miller Sujeewa Palayangoda
Krishna Panthi Gayani Pinnawala Tyler Seay Erin Shook Pradeep Wickramasiri
Post Doctoral Fellows and Visiting Scholars JiaJia Cai Nilanka Gurusinghe Sumudu Herath Sung Hyun Jang Erandi Kulawardana
Dharmika Lansakara-P Haishan Luo Mathieu Maubert Suneth Rajapaksha Maryam Shafiekhani
Mohsen Tagavifar Shayan Tavassoli Nadeeka Upamali Peixi Zhu
Chemical EOR Research Team Graduate Students Ali Afsharpoor Almas Aitkulov Reza Beygi Sriram Chandresekhar Leonard Chang Peila Chen Alex Cui Alolika Das Ghazal Dashti Shashvat Doorwar
Mehmet Erincik Pinaki Ghosh Ali Goudarzi Ruth Hahn Taylor Isbell Stephen Jong Paul Jordan Prateek Kathel Aboulghasem Kazemi Heesong Koh
Eun Song Kim Hamid Lashgari Vincent Lee Sean Li Zhitao Li Mohammad Lotfollahi Jun Lu Yiwei Ma Nhut Nguyen Nabi Nizamidin
Jose Parra Pengpeng Qi Eric Schulz Amir Shahmoradi Himanshu Sharma Robin Singh Shayan Tavassoli Songyang Tong Bingqing Wang
Undergraduate Students Alex Bennitt Ryan Casky Alex Chang Lauren Churchwell
Alex Garrido Yong Do Kim Matias Kopinsky Patrick Lim
Willie Martin Joseph Moon Travis Pitcher Christopher Sandwith
Reynaldo Torres Sarah Turley Denning Wang Enakshi Wikramanayake
Objectives • Improve understanding of surfactant retention and
ways to reduce it
• Lower the cost of chemical enhanced oil recovery by reducing surfactant retention
Surfactant Retention • What is surfactant retention?
– Loss of surfactant during a chemical flood Injected Surfactant – Recovered Surfactant = Surfactant Retention
• Causes of surfactant retention – Adsorption on clays and other mineral surfaces – Phase trapping when injected surfactant solution
forms a mixture with oil that can not be displaced in porous media
• Microemulsion viscosity • Salinity gradient
Microemulsions • Microemulsions are thermodynamically stable mixtures
of oil, water, surfactant and possibly salts, co-solvent • Three types:
– Type I: oil-in-water – Type III: comparable amount of oil and water in ME – Type II: water-in-oil
• Type III has ultra-low IFT with both oil and brine phases. This is the underlying principle for chemical EOR to recover residual oil.
• High microemulsion viscosity causes high surfactant retention
salinity
Effect of Co-solvent on Microemulsion Viscosity • Reduces the viscosity of Type III microemulsions • Mitigates the shear thinning behavior
• Self-assembly of surfactants creates meso-structures:
What Causes High Viscosity?
Differences: (1) Interface flexibility (2) Connectivity of oil (brine) domains
lamellar microstructure (interface)
oil brine
disordered bicontinuous (interface)
oil
brine
𝜇↓0 = 𝜇↓∞↑′ +∆𝜇 Newtonian background
Stress from deformation of interfaces
Viscosity:
• Adding co-solvent: – Makes the interface more flexible (reduces the bending
modules-𝒌) – Creates more connections (increases the Gaussian
modulus- 𝒌 ) • Bicontinuous microemulsion modeled as a two-domain
network:
New Model for Microemulsion Viscosity
(Two parameters: 𝑣, 𝑣↑′ )
𝜇↓0 = (1− 𝜙↓𝑜 )𝜇↓𝑤 exp(𝛼↓1 𝜙↓𝑜 )+ 𝜙↓𝑜 𝜇↓𝑜 exp(𝛼↓2 (1− 𝜙↓𝑜 )) + 𝜙↓𝑠 𝛼↓3 𝜙↓𝑜 𝜇↓𝑜 exp(𝛼↓4 (1− 𝜙↓𝑜 )+ 𝛼↓5 𝜙↓𝑜 )
1/𝜇↓0 = 1− 𝜙↓𝑜 /𝜇↓𝑤 exp(𝜈↑′ 𝜙↓𝑜 ) + 𝜙↓𝑜 /𝜇↓𝑜 exp(𝜈(1− 𝜙↓𝑜 ))
(Five parameters: 𝛼↓1 , 𝛼↓2 , 𝛼↓3 , 𝛼↓4 , 𝛼↓5 )
Old model in UTCHEM:
𝜈∝𝑘/𝑘↓𝐵 𝑇 , 𝜙↓𝑜 : volume fraction of oil in ME
Comparison of Measurements & Model Example 1
• 30% oil O1; µo=5.5 cP @ 24°C
independent measurements
1/𝜇↓0 = 1− 𝜙↓𝑜 /𝜇↓𝑤 exp(𝜈↑′ 𝜙↓𝑜 ) + 𝜙↓𝑜 /𝜇↓𝑜 exp(𝜈(1− 𝜙↓𝑜 )) ; 𝜈∝𝑘/𝑘↓𝐵 𝑇
Comparison of Measurements & Model Example 2 – Non-ideal Behavior
• 30% oil O2; µo=11.9 cP @ 25°C • 0.55% TDA-13PO-SO4, 0.2% C20-24 IOS • Co-solvent: 1% phenol-2EO
• 30% oil; • Polymer: HPAM 3630S
Comparison of Measurements & Model Examples 2&3 – Effect of Polymer
Identify and Design Better Chemicals to Lower Microemulsion Viscosity
• Ethoxylated/Propoxylated co-solvents (IBA-xEO-xPO and Phenol-xEO-xPO)
• Double-role molecules that act as both co-solvent/surfactant (2-EHS)
Mechanistic Simulations Example of Surfactant Retention by Phase Trapping
• A surfactant slug (0.3 PV) is injected and then pushed towards producers by a “polymer drive”
• If polymer drive fails to displace microemulsion, surfactant is retained. • Movies show surfactant concentration. Pattern is I-5spot and simulator
is UTCHEM.
Salinity gradient: Type I-Type III-Type I Salinity gradient: Type I-Type III-Type III
Surfactant retention=0.094 mg/gr Surfactant retention~0.28 mg/gr
Summary • Viscosity of optimum microemulsions could be
several times that of oil viscosity. • Adding co-solvent or branched surfactants is effective
to lower microemulsion viscosity • New chemicals are developed to lower microemulsion
viscosity – co-solvents: Ethoxylated/Propoxylated IBA and Phenol – Double-role molecules: 2-EHS
• A new microemulsion viscosity model is developed, validated, and implemented in UTCHEM to mechanistically simulate chemical EOR processes
Research Showcase Sponsored by
Thank you
Back up slides
Experimental artifacts Example 1: abnormal increase of viscosity with time
• Dead oil+20% toluene (µo~ 3cP @ 58C) • 0.5% C18-2EO-C18-10PO-2(SO4Na), 0.5%
C12-13-7PO-SO4-, 1% DIPA-5EO; • Sample is slightly above optimum. • ARES LS-1 with cone/plate; ~1ml sample volume
“Microemulsions are thermodynamically stable mixture …”??
Experimental artifacts Example 2: incorrect sampling before equilibrium
• Sample was not equilibrated (microemulsion + macroemulsion at the bottom)
(UV light)
Examples 2&3
Shear thinning behavior is also modeled.