Upstream oil and gas producers are trending towards increased utilization of various tertiary or enhanced oil recovery (EOR) strategies to maximize recovery of residual oil from mature reservoirs, oil that cannot otherwise be recovered feasibly by continued use of secondary recovery floods. Among these EOR strategies is the incorporation of tailored chemicals in water floods that improve late-stage flood sweep efficiencies, resulting in increased incremental oil recovery yields. Producers are using designed polymers, surfactants and alkaline agents, alone or in combination to create higher yielding tertiary water floods. It is common for Oil and Gas Producers to utilize chemically enhanced oil recovery (cEOR) strategies within their portfolio of producing operations.
ClearBakk was contracted to design, procure, fabricate and package a 4.8 t/day polymer hydration plant (PHP) for deployment in a producer’s Alaskan North Slope Prudhoe Bay operation. By employing polymer-thickened water floods, the producer aims to generate more heavy oil from mature wells.
Prior to project order, ClearBakk collaborated with the producer and the selected dry polymer supplier to establish an appropriate project design basis, including process design, module building configurations, off module layouts while also accounting for the complete range of required site tie-ins. The process design was based on preparing and delivering 4.8 t/day of fully hydrolyzed polyacrylamide (PAC) dry polymer in a 1% solution, with feed to reservoir injection pumps. Project order to custody transfer at site took a period of 28 weeks. The PHP comprised of three (3) process module buildings – Primary Wetting, Solution Aging, Utilities (including instrument air and nitrogen generation) as well as an off skid Dry Polymer Storage area, all installed on foundations comprised of either rig mats or pilings.
During the design phase, ClearBakk focused on tackling challenges inherent in freezing weather operation and integration within the producer’s production platform:
- Freezing weather operation necessitated specifying select insulation, vessel materials, cladding and cold weather shielding within the Polymer Storage Silo unit. Flexible pipe connections between module building ensures piping integrity against shifting caused by frost heaves.
- Protection against polymer degradation in the primary wetting and solution aging units was achieved by employing nitrogen gas blanketing and appropriate wetted parts metallurgy.
- Integration of the PHP with the producer’s injection philosophy was achieved by customizing the solution aging vessel design to support a continuous/batch mode process control scheme in the solution aging unit, ensuring the PHP will keep pace with changes in demand polymer flood flow rates coming from the producer’s production field.
ClearBakk also incorporated into this project, its proprietary water wall funnel design to achieve critically important initial wetting of dry polymer. The viscosity of the final solution pumped to the production platform is over 1,100 cP.
The PHP is controlled through a stand-alone control system located in the MCC/Utility building using an Allen-Bradley ControlLogix main control panel with a PanelView HMI. The project achieved reduced wiring utilizing smart motor starters and VFD’s relying on soft communication for regular control.
Design, procurement, fabrication and installation comply with all applicable North Slope Borough, Alaska state, and US federal codes and regulations. Before shipping to site, all process tanks and vessels were leak tested and all process piping was hydrostatically tested. Final factory acceptance testing (FAT) was also completed at the module yard in Calgary prior to shipping.
ClearBakk’s EPCM expertise is applied to facilities engineering, polymer hydration and water treatment design and package construction with a proven history serving a wide range of clients in Western Canada and across North America. Our corporate philosophy is people and technology. We leverage the right processes and technology to optimize project cost and performance for our clients.
Learn more about ClearBakk at: https://clearbakk.com/projects/