R12 hydrate formation kinetics based on laser light scattering technique

Abstract

A circulating flow system consisting of a transparent U-bend flow loop, a mixing tank and a laser granulometer was set up for studying the kinetics hydrate formation and the pressure is up to 4 MPa. Refrigerant CCl₂F₂ (R12) hydrate formation experiments were performed using laser light scattering method at 277.1 K and pressures of 0.24 and 0.32 MPa. The liquid flow rates were in the range of 300–1400 L/h. The size distribution and density of R12 hydrate particles in pure water were measured using a laser granulometer. Experimental results show that the size of hydrate particles increases sharply at the initial stage and approaches gradually to a stable size. The hydrate particle concentration in the aqueous phase increases with pressure and circulating liquid flow rate. Based on the material balance, the mathematical model among gas consumption, average hydrate particle size and shading ratio has been established. The calculated results using the mathematical model accord well with the experimental gas consumption data.