During the last decade

reports on the topic of the kinetics of hydrate formation have been appearing focusing on the batch reactor or horizontal pipe. However

there are still less studies on this topic applying in the vertical special-shaped tube

for example internal spiral-grooved tube (ISGT).To investigate such multi-component gas (natural gas)-water-surfactant system during the hydrate formation process

CFD method combining with population balance model (PBM) was utilized to simulate gas-liquid mass transfer coefficient in the ISGT

based on the solute permeation model and Kolmogorov isotropic turbulence theory. The hydrate formation kinetics model in ISGT was modelled after extending the classical hydrate nucleation and growth theory proposed by Kashchiev and Firoozabadi for a single component gas-water system to the multi-component gas (natural gas)-water-sodium dodecyl sulfate system. According to the classical crystallization theory

the hydrate growth model was modified by the simulated gas-liquid mass transfer coefficient. The averaged gas-liquid mass transfer coefficients for natural gas in the water at hydrate production conditions are determined by CFD simulation. Furthermore

Microsoft Visual C++ software was utilized to obtain data of the natural gas hydrate formation kinetics. The results show that the nucleation rate of natural gas hydrate decreases sharply with the increase of the effective surface energy of the reaction system

while the driving force and growth rate of hydrate nucleation are not affected by the effective surface energy. Meanwhile

the hydrate growth rate increases with the increase of the flow rate and reaction pressure

the decrease of the temperature. The nucleation rate increases with the increase of the pressure and the decrease of the temperature. The results are promising to pave ways to further experimental and theoretical investigation on hydrate formation.