Effect of nanoparticles on the nucleation and agglomeration rates of hydrate growth using THF\u2013water clathrates

Abstract

Four types of nanoparticles, amorphous carbon, iron III oxide, SiO2, and amino-coated SiO2, were tested to determine changes in tetrahydrofuran–water (THF–water) clathrate hydrate nucleation and agglomeration. Rates were experimentally found to determine their viability for preventing natural gas hydrates from developing during offshore drilling operations. THF–water clathrates were chosen as a model to represent gas hydrate growth at atmospheric pressure. Concentrations of each nanoparticle between 0.15% and 1.0% by weight were tested as a kinetic inhibitor to hydrate formation. Tests were repeated at various temperatures below the formation temperature of 4.4 °C for THF–water clathrate hydrates. Measurements were made to identify how the concentration of THF affects the clathrate hydrates forming under static conditions between 20% and 30% by mole of THF. The primary tests in this study were performed using a 20:80 THF/water ratio. Temperature increases during hydrate nucleation for THF–water were measured between − 5 and 3 °C. The range of ideal nanoparticle concentrations was found to be between 0.15% and 0.45% by weight for optimal static, kinetic inhibition of hydrate nucleation. At approximately 0.3% by weight, the most significant inhibition was observed under static conditions for all four types of nanoparticles tested. We found that functionalized amino-coated SiO2 nanoparticles, across all tests, significantly increased the time required for the formation of THF–water clathrate hydrates compared to the other three non-functionalized nanoparticles. The amorphous carbon and iron III oxide nanoparticles performed similarly across each test and were both the least effective in their inhibition of the clathrate hydrates of the four nanoparticles studied compared to a control.