In February 2016, The University of Calgary released an SPE paper, Minimize Formation Damage in Water-Sensitive Unconventional Reservoirs by Using Energized Fracturing Fluid, (SPE-179019-MS).
The paper is focused on the Montney formation and the use of nitrogen (N2) and carbon dioxide (CO2) as energized water-based fracturing fluids in water sensitive formations.
Two of Ferus’ SPE papers are referenced:
SPE 168632 – ‘A Comparison of the Effectiveness of Various Fracture Fluid Systems Used in Multi-Stage Fractured Horizontal Wells: Montney Formation, Unconventional Gas’
SPE 149344 – ‘Improved Hydraulic Fracture Performance with Energized Fluids: Montney Example’
This work provides critical insights into understanding the performance of using energized fracturing fluid to mitigate formation damage in tight formations. Energized fluids have been widely used in water-sensitive formations as they can minimize fluid leak-off during fracturing, and achieve higher load fluid recovery during flowback and better production.
The paper concludes N2 foam leads to the highest load fluid recovery in the Montney formation.
Summary of the paper:
Focused on Montney formation of British Columbia and Alberta;
Slickwater is damaging the formation by both clay swelling and aqueous phase trapping (capillary imbibition);
Relates higher foam quality to higher Initial Productivity (IP’s) and higher Estimated Ultimate Recoveries (EUR’s);
Relates better production to better load fluid recoveries achieved with foamed fracture fluids.
Impact of Foam Quality on Initial Rate and Cumulative Gas Recovery
Source: SPE 179019