Estimating Shale Maturity from Ultra-Fast Microwave Heating

• Main Authors: Alvarez, Jose Oliverio, Jacobi, David, Srinivasan, Poorna, Rodriguez, Jennifer
• Format: Conference Proceeding
• Language: English
• Subjects: Antenna measurements; Electromagnetic heating; Microwave antennas; Microwave heating; Microwave measurement; Microwave theory and techniques; permittivity measurements; productivity index; shale maturity; Temperature distribution; Temperature measurement
• ISSN: 2474-2740
• DOI: 10.23919/AMTA55213.2022.9955014

A microwave system for heating and testing of geological applications was tested with different shale samples. The system consists of a dual-mode microwave cavity, where heating and measuring is performed simultaneously with two different microwave sources. The measurements were done at around 2.16 GHz. The cavity had a diameter of 104.92 mm and a height of 85 mm. A small shale sample of 9.8 mm diameter by 15 mm height was introduced in a quartz vial with an inner diameter of 9.8 mm and 120 mm height. Depending on the electrical losses, the sample could be heated up to 1200°C. Initial complex permittivity measurements showed that the imaginary part exhibited a relaxation process at specific temperature ranges. These temperature ranges correlated with the expected temperatures of the S1 and S2 peaks of the pyrolysis method, from which we could compute the equivalent vitrinite reflectance of the sample; this was an indicator of maturity. This allowed for quick estimates of maturity, which allowed for real time decisions on the development of unconventional resources.