Investigation of Inhibition Effect of Wax on Hydrate Decomposition in Emulsions

During the development and production of offshore oil and gas, the deposition of hydrate and wax in low-temperature and high-pressure flow pipelines can pose a serious risk of blockage. Common methods for plugging removal include reducing pressure, heating, and injecting chemical inhibitors. However, the hydrate decomposition mechanism in the presence of wax during the plugging removal process is still unclear. This study used a high-pressure reactor to investigate the decomposition process of hydrate in wax containing systems, and analyzed the pressure drop trend and hydrate morphology. The results show that the wax will wrap the hydrate particles in the gel like structure, restrict the diffusion of gas into the gas phase space, and thus delay the decomposition of hydrate. The gas release rate and average decomposition rate both decrease with the increase of wax concentration. In a system containing 10 wt% wax, the removal time is more than ten times longer than in a system without wax. This study elaborates on the inhibition effect of wax on the decomposition behavior of hydrate, providing a theoretical basis for flow assurance in marine oil and gas production.