SMP Preparation, Programming, and Characterization

Description

The problem of loss circulation in geothermal wells is inherently challenging due to high temperatures, brittle rocks, and presence of abundant fractures. Because of the inherent challenges in geothermal environments, there are limitations in selecting proper lost circulation materials (LCMs). Traditional LCMs such as calcium carbonates that are commonly used in the oil and gas drilling may be softened and prone to failure during geothermal drilling. Moreover, evaluating the performance of different LCMs for geothermal drilling requires unique testing setups, which is expensive, and complicated to run due to harsh environmental conditions of geothermal systems. Herein, we present a numerical approach to simulate LCM transport and bridging through fractures in downhole conditions. By discrete element methods, each individual particle trajectory, and their interactions with the fluid and surrounding particles are incorporated into the analysis. To validate the model, we used experimental results acquired from a high-temperature flow loop system built specifically for this purpose. We took a further step in this work and considered LCM particles that are made from a shape memory polymer (SMP). These particles start expanding and adhering to each other in downhole conditions. The use of SMP is shown to be advantageous in sealing large fractures (3 mm aperture). We demonstrated how numerical modelling may supplement laboratory tests to show initiation of the bridging process, fracture plugging or even its failure. Using the proposed methodology may significantly reduce the number of experiments needed to find an effective LCM recipe, hence drillers can save time and costs by assessing different LCM systems numerically.

Resources

Name Format Description Link
33 Paper title "Modelling of cohesive expandable LCMs for fractures with large apertures" associated with these data. The paper was published in Geothermics 104 (2022) 102466. https://gdr.openei.org/secure_dl?fp=files%2F1459%2FGeothermics_Modelling+of+cohesive+expandable+LCMs+for+fractures+with+large+apertures.pdf
33 Paper title "Modelling of cohesive expandable LCMs for fractures with large apertures" associated with these data. The paper was published in Geothermics 104 (2022) 102466. https://gdr.openei.org/files/1459/Geothermics_Modelling%20of%20cohesive%20expandable%20LCMs%20for%20fractures%20with%20large%20apertures.pdf
10 The SMP was synthesized out of a readily available commercial epoxy resin (EPON 826, a bisphenol-based resin) cured by an isophorone diamine (IPD) crosslinker. Each 100g EPON 826 was bonded with 23.2 g IPD to balance out the stoichiometry. https://gdr.openei.org/files/1461/SMP%20preprarion.docx
10 Dynamic Mechanical Analysis (DMA) test was conducted on the specimen. The glass transition range is between 250 degrees and 300 degrees C. This suggests that the polymer has a very high glass transition temperature. Also, based on our previous experience, we believe that this polymer will not only have an excellent shape memory effect but will also have huge recovery stress due to its high storage modulus at a rubbery state. https://gdr.openei.org/files/1461/Dynamic%20Mechanical%20Analysis%20%28DMA%29.docx
10 The free shape recovery experiment was conducted by putting the programmed specimen in an oven at 275 degrees C for 60 min. The height of the recovered specimen was measured to calculate the shape recovery ratio. https://gdr.openei.org/files/1461/SMP%20Programing.docx

Tags

  • processed-data
  • modeling
  • discrete-element-methods
  • lost-circulation-material
  • dem
  • economic
  • lost-circulation
  • drilling
  • lcm
  • fracture-sealing
  • technology
  • cfd
  • computational-fluid-dynamics
  • shape-memory-polymer
  • smp
  • geothermal
  • energy

Topics

Categories