Experimental study on micron-sized sand particles transport in the water flow path of hydrates production wellbore

Micron-sized sand settlement in wellbore has led to the failure of several hydrate production tests. Therefore, research on the migration of micron-sized sand particles in hydrate production wellbore is of great significance. In this paper, 384 groups experiments were conducted to study the effect of flow rate, volumetric concentration of sand production (VCSP), sand-diameter and hole inclination on the transport and settlement of micron-sized sand particles. Results suggested that higher flow rate, smaller sand-diameter, lower inclination and smaller VCSP all led to lower sand settlement. A model was developed for the prediction of sand concentration ratio using nonlinear regression. The predictions were in good correspondence with the experimental data. The differences of solid particle transports during hydrate production, conventional oil & gas production and drilling were analyzed. The results presented here provide a useful reference for the determination of a reasonable hydrate production system. •Micron-sized sand transport in water flow of hydrate production wellbore was studied.•The migration law of micron-sized sand in hydrate production is different from that of cuttings in drilling.•Effects of flow rate, sand diameter, hole inclination and volumetric concentration of sand production were studied•A model was developed to predict sand concentration ratio in wellbore.