Experimental Investigation of Polymer-Induced Fouling of Heater Tubes in the First-Ever Polymer Flood Pilot on Alaska North Slope
- Anshul Dhaliwal (University of Alaska Fairbanks) | Yin Zhang (University of Alaska Fairbanks) | Abhijit Dandekar (University of Alaska Fairbanks) | Samson Ning (Reservoir Experts, LLC/Hilcorp Alaska, LLC) | John Barnes (Hilcorp Alaska LLC) | Reid Edwards (Hilcorp Alaska LLC) | Walbert Schulpen (Hilcorp Alaska LLC) | David Cercone (Department of Energy National Energy Technology Laboratory) | Jared Ciferno (Department of Energy National Energy Technology Laboratory)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- October 2020
- Document Type
- Journal Paper
- 2020.Society of Petroleum Engineers
- polymer flooding pilot, polymer induced fouling, heat exchanger, Alaska North Slope, heavy/viscous oil
- 10 in the last 30 days
- 17 since 2007
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Polymer flooding is being pilot tested for the first time in the Schrader Bluff viscous oil reservoir at the Milne Point Field on Alaska North Slope (ANS). One of the major concerns of the operator is the impact of polymer on the oil production system after polymer breakthrough, especially the polymer-induced fouling issues in the heat exchanger. This study investigates the propensity of polymer fouling on the heater tubes as a function of different variables, with the ultimate goal of determining safe and efficient operating conditions. A unique experimental setup was designed and developed in-house to simulate the fouling process on the heating tube. The influence of heating tube skin temperature, tube material, and polymer concentration on fouling tendency was investigated. Each test was run five times with the same tube, and in each run, the freshly prepared synthetic brine and polymer solution was heated from 77°F to 122°F to mimic field-operating conditions. The heating time and fouling amount were recorded for each run. Cloud point measurement has also been conducted to find the critical temperature at which the polymer in solution becomes unstable and precipitates out. The morphology and composition of the deposit samples were analyzed by environmental scanning electron microscopy (ESEM) and X-ray diffraction (XRD), respectively. It was found that the presence of polymer in produced fluids would aggravate the fouling issues on both carbon steel and stainless steel surfaces at all tested skin temperatures. Only higher skin temperatures of 250°F and 350°F could cause polymer-induced fouling issues on the copper tube surface, and the fouling tendency increased with polymer concentration. At the lower skin temperatures of 165°F, no polymer-induced fouling was identified on the copper tube. A critical temperature that is related to the cloud point of the polymer solution was believed to exist, below which polymer-induced fouling would not occur and only mineral scale was deposited but above which the polymer would aggravate the fouling issue. The cloud point of the tested polymer solution was determined to be between 220°F and 230°F. From a practical safer design standpoint, we recommend a value of 220°F for operational purposes on the pilot site. The heating efficiency of the tube would be decreased gradually as more fouling material accumulates on its surface. If polymer precipitated and deposited on the surface, it would bond to the mineral crystals to form a robust three-dimensional network structure, resulting in a rigid polymer-induced fouling. The study results have provided practical guidance to the field operator for the ongoing polymer flooding pilot test on ANS.
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Cao, G., Liu, H., Shi, G. et al. 2007. Technical Breakthrough in PCPs’ Scaling Issue of ASP Flooding in Daqing Oilfield. Paper presented at the SPE Annual Technical Conference and Exhibition, Anaheim, California, USA, 11–14 November. SPE-109165-MS. https://doi.org/10.2118/109165-MS.
Cheng, Y., Czyzewski, W., Zhang, Y. et al. 2018. Experimental Investigation of Low Salinity Waterflooding To Improve Heavy Oil Recovery from the Schrader Bluff Reservoir on Alaska North Slope. Paper presented at the Offshore Technology Conference, Houston, Texas, USA, 5–7 November. OTC-29117-MS. https://doi.org/10.4043/29117-MS.
Crabtree, M., Eslinger, E., Fletcher, P. et al. 1999. Fighting Scale—Removal and Prevention. Oilfield Rev 11 (3): 35–45.
Dandekar, A., Bai, B., Barnes, J. et al. 2019. First Ever Polymer Flood Field Pilot—A Game Changer To Enhance the Recovery of Heavy Oils on Alaska’s North Slope. Paper presented at the SPE Western Regional Meeting, San Jose, California, USA, 23–26 April. SPE-195257-MS. https://doi.org/10.2118/195257-MS.
Kazi, S. N., Teng, K. H., Zakaria, M. S. et al. 2015. Study of Mineral Fouling Mitigation on Heat Exchanger Surface. Desalination 367: 248–254. https://doi.org/10.1016/j.desal.2015.04.011.
Mittal, S., Anand, S., Venkat, P. S. et al. 2018. Influence of EOR Polymers on Fouling in Production Wells and Facilities. Paper presented at the Abu Dhabi International Petroleum Exhibition & Conference, Abu Dhabi, UAE, 12–15 November. SPE-192943-MS. https://doi.org/10.2118/192943-MS.
Moradi-Araghi, A. and Doe, P. H. 1987. Hydrolysis and Precipitation of Polyacrylamide in Hard Brines at Elevated Temperatures. SPE Res Eval & Eng 2 (2): 189–198. SPE-13033-PA. https://doi.org/10.2118/13033-PA.
Muller, G., Fenyo, J. C., and Selegny, E. 1980. High Molecular Weight Hydrolyzed Polyacrylamides. III. Effect of Temperature in Chemical Stability. J Appl Polym Sci 25 (4): 627–633. https://doi.org/10.1002/app.1980.070250409.
Oliveira, P. F., Costa, J. A., Oliveira, L. F. S. et al. 2019. Hydrolysis and Thermal Stability of Partially Hydrolyzed Polyacrylamide in High-Salinity Environments. J Appl Polym Sci 136 (29): 47793. https://doi.org/10.1002/app.47793.
Pospisil, G. 2011. Heavy Oil Challenges & Opportunities North Slope Alaska. Powerpoint presentation, https://www.aoga.org/wp-content/uploads/2011/01/8.-Pospisil-Heavy-Viscous-Oil.pdf (6 January 2011).
Ramsden, D. K. and McKay, K. 1986. Degradation of Polyacrylamide in Aqueous Solution Induced by Chemically Generated Hydroxyl Radicals: Part I—Fenton’s Reagent. Polym Degrad & Stabil 14 (3): 217–229. https://doi.org/10.1016/0141-3910(86)90045-5.
Ryles, R. G. 1988. Chemical Stability Limits of Water-Soluble Polymers Used in Oil Recovery Processes. SPE Res Eval & Eng 3 (1): 23–34. SPE-13585-PA. https://doi.org/10.2118/13585-PA.
Seright, R. S. and Skjevrak, I. 2015. Effect of Dissolved Iron and Oxygen on Stability of HPAM Polymers. SPE J. 20 (3): 433–441. SPE-169030-PA. https://doi.org/10.2118/169030-PA.
Shupe, R. D. 1981. Chemical Stability of Polyacrylamide Polymers. J Pet Technol 33 (8): 1513–1529. SPE-9299-PA. https://doi.org/10.2118/9299-PA.
Teng, K. H., Kazi, S. N., Amiri, A. et al. 2017. Calcium Carbonate Fouling on Double-Pipe Heat Exchanger with Different Heat Exchanging Surfaces. Powder Technol 315: 216–226. https://doi.org/10.1016/j.powtec.2017.03.057.
Wang, Q., Al-Naseer, W., Al-Dawood, F. et al. 2017. Inhibition of Calcium Carbonate Scale in the Presence of EOR Chemicals. Paper presented at the SPE International Conference on Oilfield Chemistry, Montgomery, Texas, USA, 3–5 April. SPE-184534-MS. https://doi.org/10.2118/184534-MS.
Wylde, J. J., Allan, K. J., McMahon, J. et al. 2011. Scale Inhibitor Application in Northern Alberta: A Case History of an Ultra High Temperature Scale Inhibition Solution in Fire Tube Heater Treaters. Paper presented at the SPE International Symposium on Oilfield Chemistry, The Woodlands, Texas, USA, 11–13 April. SPE-14100-MS. https://doi.org/10.2118/14100-MS.
Wylde, J. J., McMahon, J., and Mayner, S. 2010. Scale Inhibitor Application in Northern Alberta: A Case History of an Ultra High Temperature Scale Inhibition Solution in Fire Tube Heater Treaters. Paper presented at the SPE International Conference on Oilfield Scale, Aberdeen, Scotland, UK, 26–27 May. SPE-130307-MS. https://doi.org/10.2118/130307-MS.
Wylde, J. J., Slayer, J. L., and Barbu, V. 2013. Polymeric and Alkali-Surfactant Polymer Enhanced Oil Recovery Chemical Treatment: Chemistry and Strategies Required after Breakthrough into the Process. Paper presented at the SPE International Symposium on Oilfield Chemistry, The Woodlands, Texas, USA, 8–10 April. SPE-164078-MS. https://doi.org/10.2118/164078-MS.
Xiong, B., Loss, R. D., Shields, D. et al. 2018. Polyacrylamide Degradation and Its Implications in Environmental Systems. npj Clean Water 1 (1): 17. https://doi.org/10.1038/s41545-018-0016-8.
Zheng, F. F., Quiroga, P., and Sams, G. 2011. Challenges in Processing Produced Emulsion from Chemical Enhanced Oil Recovery—Polymer Flood Using Polyacrylamide. Paper presented at the SPE Enhanced Oil Recovery Conference, Kuala Lumpur, Malaysia, 19–21 July. SPE-144322-MS. https://doi.org/10.2118/144322-MS.