Measurement and Prediction of Thermal Degradation of Scale Inhibitors

作者：Wang Wei^*; Kan Amy T; Zhang Fangfu; Yan Chao; Tomson Mason B

来源：SPE Journal, 2014, 19(6): 1169-1176.

DOI：10.2118/164047-PA

As the oil and gas industry is making firm strides in deepwater and shale exploration and development, possible thermal degradation of scale-inhibitor molecules poses a great challenge for scaling control and flow assurance for high-temperature reservoirs. Although extensive research has been conducted to test thermal stability of scale inhibitors, little work has been devoted to study the thermodynamics/kinetics of thermal degradation of scale inhibitors. In this work, a novel and efficient testing approach based on inhibition kinetics has been developed and successfully applied to determine the fraction of the active inhibitor molecules in pre-heated samples of scale inhibitors with various generic chemistries. Moreover, for the first time, we have modeled the kinetics of inhibitor thermal degradation on the basis of the integrated first-order rate equation and Arrhenius equation, with good agreements between the model predictions and experimental data. The pre-heated scale inhibitors have been analyzed by nuclear-magnetic-resonance (NMR) spectroscopy for organic-compound characterization. Our results and predictions based on inhibition testing assay are consistent with the P-31/H-1 NMR analyses. This work has enabled an in-depth understanding of the time and temperature dependence of thermal degradation of scale inhibitors, and facilitates the rational selection and deployment of scale inhibitors for high-temperature oil and gas production.

• 出版日期2014-12