Effect of nanofluid and SDS compound system on natural gas hydrate formation

Abstract

As a compound multi-phase dispersion system, nanofluids can enhance the energy transfer performance of solutions and are considered to be effective in promoting the formation of hydrates. Hence, in this study, a compound system of SiO2 nanofluid and sodium dodecyl sulfate (SDS) solution at 6 MPa and 275.15 K was used to study the effects of Cu and SiO2 nanofluids on CH4 hydrate formation at different concentrations, and the results were compared. The results showed that the Cu nanofluids promoted the formation of natural gas hydrates. At lower Cu nanofluid concentrations, the gas storage capacity of the hydrates increased with increasing Cu nanofluid concentration. At a concentration of 2200 ppm, the gas storage capacity reached 111.57 V g/V w. However, the SiO2 nanofluid only promoted the formation of hydrates at lower concentrations. The gas storage capacity reached 108.26 V g/V w at a concentration of 800 ppm. As the concentration of the SiO2 nanofluid increased, the gas storage capacity of the hydrates gradually decreased, and hydrate formation was eventually inhibited. Therefore, reasonable selection of the type and concentration of nanofluids is required to improve the gas storage capacity of hydrates.