Experimental investigation of polymer induced fouling of heater tubes in the first-ever polymer flood pilot on Alaska North Slope

• Main Author: Dhaliwal, Anshul
• Other Authors: Dandekar, Abhijit, Zhang, Yin, Goering, Douglas J.
• Format: Thesis
• Language: English
• Published: 2021
• Subjects: Heat exchangers; Polymer flooding; Enhanced oil recovery; Petroleum engineering; Fouling; Master of Science in Petroleum Engineering; Fairbanks; Milne Point; Alaska North Slope; north slope; Alaska
• Online Access: http://hdl.handle.net/11122/12607

Thesis (M.S.) University of Alaska Fairbanks, 2021 Mineral fouling in heat exchangers has been extensively investigated by researchers in recent times. The oil and gas industry has a long history of fouling issues in production systems as a result of produced fluids treatment. Due to decline in production rates in oilfields new technologies are being developed and field tested in pilots. Polymer flooding is one such technology that involves addition of polymers to injection fluids to enhance oil production. A polymer flood pilot has been set up in the Schrader Bluff viscous oil reservoir at Milne Point field on the Alaska North Slope (ANS). The results from the pilot are encouraging, however a major concern of the operator is the influence of polymer on the production system after breakthrough, especially the fouling in heat exchangers. 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. This work applies a multi-experimental approach to study the severity of polymer-induced fouling in both dynamic and static states of produced fluids as well as studying the stability of polymer solutions at different temperatures. 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. Dynamic Scale Loop (DSL) tests were conducted to study fouling due to polymer at different temperatures (165°F to 350°F) in a dynamic state of fluid flow where the fluids mimic the residence time of fluids in the heat exchanger on the field pilot. Cloud point ...