At-the-Bit Mud Loss Control - Demonstration of a New Mud Loss Control Methodology and Tool Converting the Drilling Mud to a Downhole Pill.

A new and innovative drilling tool has been developed to control large mud losses during drilling. The innovation is to transform the circulating drilling mud into a downhole swelling pill to seal off fractured rocks that are penetrated by the drill bit. The new technique uses a tailor-made polymer designed for use with drilling mud. The project is led by Prores and an international collaboration has been established with both oil companies, suppliers and the service industry. The value potential of the new tool is very large through more efficient drilling operations and through unlocking new hydrocarbon reserves that are not drillable with current technologies. Design, engineering and fabrication are performed by EnergyX in collaboration with Prores. Both functional and stress testing have been performed in a well at Xrig. The status is that industrial versions have been produced for use in well pilots. The first pilot will be conducted in June 2022 at a test field in Oklahoma. The second pilot is planned on a real oil field in Oman in the autumn of 2022.

The At-the-Bit project has been organized as Joint Industry Project (JIP) with support from Equinor, ConocoPhillips, Lundin and ARA Petroleum in Oman in addition to the DEMO support from the Research Council of Norway. The main achievements from the project have been: 1- A new methodology and technologies have been developed to combat severe mud losses during drilling. The activities included; design, engineering, fabrication and testing at yard and test well facilities at EnergyX and Xrig at Ålgård outside Stavanger. 2- Along with the JIP members and technology partners new mud loss treatment services have been discussed in the light of a possible commercialization of the technology. 3- A full scale functional prototype has been developed as a preparation for well piloting. A first pilot is planned to be executed at Catoosa Test Facility in Oklahoma during June / July 2022 as a part of next phase of the project (Phase 4).

The At-the-Bit project aims at developing an on-demand and instant downhole solution for treatment of severe and total mud loss. The circulating drilling mud will be converted downhole to a swelling pill by use of a super absorbent polymer. In a final version, this polymer will be pre-stored and activated by a downhole tool installed as a part of the BHA and drillstring. The fast swelling polymer will follow the mud loss pathway and seal off the throats of fractures and faults. This tool can be regarded as a "Driller's Airbag". The special made polymer will swell around 60 times in 2 - 30 minutes and 400 litres of polymer will give 10 m^3 of swelled pill. The At-the-Bit technology development is following two major pathways; one for the development of the polymer and the other for the downhole tool development. The status of the project is that the polymer has been developed together with our partner SNF in France and qualified in the laboratory under HPHT conditions. Real mud for the experiments has been provided by Lundin in Norway. A JIP project has been established for phases one and two (polymer development and early field trials onshore Oman). The project is being supported by Lundin, Equinor, ConocoPhillips and ARA Petroleum in Oman (in kind support). The objective of this DEMO2000 application is to qualify the new polymer for use in pilot wells to demonstrate the functionality of the polymer when circulating from the surface. The plan is to execute the pilot in onshore wells in Oman at a field with known mud losses challenges. The challenges for qualifying the polymer for downhole use are to be able to circulate and displace the carrier fluid suspended polymer grains without any unwanted swelling. Contamination may trigger an early activation of the polymer and create gel inside the drillstring with potential plugging. Also, the pilots will give data on fractured formation sealability.