Rex Hjelm Presents his Work at SSRL and LCLS Users’ Conference

Rex Hjelm Presents his Work at SSRL and LCLS Users’ Conference

New Mexico Consortium (NMC) and Los Alamos National Laboratory (LANL) scientist Rex Hjelm will present his work at the joint Stanford Synchrotron Radiation Lightsource (SSRL) and the Linac Coherent Light Source (LCLS) Users’ Conference will be held online in September 20-24, 2021.

The goal of the conference is to bring together researchers in all areas of fundamental and applied diffraction and crystallographic research to present current topics.  The program includes femtosecond diffraction methods, hybrid methods for structural biology, powder diffraction and material science research, new ideas in crystallography and exciting macromolecular structures.

The organizers of this conference include Vincent Noël, Eleanor Spielman-Sun, Adam D. Jew, John R. Bargar (SSRL/SLAC), and Yun Liu (CNR/NIST).

His presentation, which will be held in the Synchrotron and Neutron Investigations of Deep subsurface Energy Systems session is titled, “Enhanced Oil Recovery from Tight Shale Probed by Small-angle Neutron Scattering Techniques Emulating Field Conditions”. This session is scheduled for Friday Sept 24th at 1-5pm (Pacific Daylight Time).

The presentations in this session will further define new research opportunities in combining and coordinating neutron and synchrotron techniques to enhance our knowledge of physical and chemical changes in subsurface geological systems.

In this presentation, Rex will discuss the work of the LANL/NMC team to understand the extraction of hydrocarbons from nano to mesoscale pores (nanometers to a few micrometers) in tight shale in order to extend and improve the production of wells, once the more easily extracted oil is exhausted. Regardless of the small size of the hydrocarbon containing pores, they hold a significant amount of valuable material.

The objectives of this research is to measure the size distributions of pores and the distribution of hydrocarbon among the pores and the pore size related access of fluids used to extract hydrocarbons in this difficult to access very small pore size regime. The properties of small-angle neutron scattering make it uniquely capable for meeting these objectives. The method probes the relevant length scales. The neutrons are highly penetrating, allowing interrogation of geological samples, such as oil shale, in robust sample environments that emulate the temperature and pressure condition encountered in the field.

The most unique property of the technique is the difference between scattering properties of neutrons of fluids containing molecules where the hydrogen isotope, deuterium is substituted for hydrogen. This allows “contrast matching” of the scattering from fluid-filled pores with the scatter from the shale matrix, making them “disappear”, giving a determination of the size distribution of pores that are accessible to the fluid.

This method is used to determine the sizes of pores that are accessible to deuterated hydrocarbon surrogate for oil in imbibed shale samples with different compositions and the efficacy of fluid removal by other fluids used in field extraction processes.

This study informs extraction strategies considering pressures used in the extraction procedures and the importance of the shale chemical composition in the efficacy of extraction.

To learn more about the Stanford Synchrotron Radiation Lightsource (SSRL) and the Linac Coherent Light Source (LCLS) Users’ Conference see: