Investigation of wax on hydrate formation in emulsions: Dual-scale experiments and mechanism

Hydrate and wax phase transitions are typical flow risks during oil and gas development. The wax on hydrate formation was systematically studied based on dual-scale experimental platform. The sensitivity analysis on hydrate growth illustrates that the wax inhibits hydrate growth and the maximum reduction of hydrate growth rate is 79.6 % in waxy emulsions, and the wax on hydrate conversion ratio decreased the most by 27.2 %. The promoting effect of water content, subcooling, and stirring rate on hydrate growth increased by more than 10 times, 2 times, and 7 times, respectively. The droplet size first decreases and then increases as the wax concentration increases in emulsions. The mechanism of hydrate growth in waxy emulsions considers bidirectional growth and pores renewal of hydrate particles, and the mean error of the prediction model is 8.4 %. This work provides data basis and theoretical foundation for flow assurance management in oil and gas filed.