Self-Repairing Polymer-Modified Cements for High Temperature Geothermal and Fossil Energy Applications

Journal Article · Fri May 01 00:00:00 EDT 2020 · Geothermics

DOI:https://doi.org/10.1016/j.geothermics.2019.101790· OSTI ID:1580580

Rod, Kenton A.  ^[1]; Fernandez, Carlos A.  ^[1]; Koech, Phillip K.  ^[1]; Dai, Gao L. ^[1]; Correa, Miguel  ^[1]; Huerta, Nicolas J. ^[2]; Burton, Sarah D. ^[1]; Miller, Quin RS ^[1]; Resch, Charles T. ^[1]

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1. BATTELLE (PACIFIC NW LAB)
2. National Energy Technology Laboratory

In this work five novel polymer-cement composite formulations were prepared and evaluated as potential cementitious material alternatives to conventional wellbore cement. These cement composites were cured at 200 °C and their mechanical properties, including compressive strength, Young modulus, shear bond strength to steel casing, and self-healing and re-adhering (to steel) capability. Thermal stability was also evaluated by curing these cement materials at 200 °C for up to one month followed by determining their mineralogy and chemical composition by X-ray diffraction spectroscopy, 13C NMR, and total organic carbon. Permeability analysis was performed before and after healing a longitudinal fracture on unmodified cements and polymer-cement composites with the later showing lower (2nd/1st) permeability ratios with respect to base cements. Furthermore, a reduction in permeability of up to 80X on average with respect to their unmodified (base) cement, was observed in two polymer-cement formulations suggesting that the introduction of these polymers bring about self-healing capability. Two of the best performing polymer-cement composites were exposed to 30-day curing period at 200 °C showing that their self-healing capability is maintained. The composite stability is associated to the fact that the polymer material is stable as demonstrated by total organic carbon and NMR spectroscopy. These advanced polymer-cement composites with higher ductility and self-healing capability could be used as alternative wellbore cement materials for geothermal and fossil energy applications.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1580580
• Report Number(s): PNNL-SA-140314
• Journal Information: Geothermics, Vol. 85
• Country of Publication: United States
• Language: English