Natural gas hydrates

intricate crystalline structures formed by water molecules and small gas molecules

have emerged as a significant and globally impactful clean energy resource. However

their commercial exploitation faces challenges

particularly operational disruptions caused by sand-related blockages. Understanding the rheological properties of hydrate slurry

especially in the presence of micron-sized sand particles

is imperative for ensuring the flow assurance of subsea hydrate exploitation. This study extensively investigates the rheological properties of sand-containing hydrate slurries. The findings reveal that these slurries exhibit non-Newtonian fluid characteristics

including yield stress

thixotropy

and shear-thinning behavior. Solid-like elastic features are observed in sand-containing hydrate slurries before yielding

transitioning to viscous behavior after yielding. Even with a minimal amount of sand

both static yield stress and yield strain experience substantial changes

correlating with the increase in sand concentration. The research conclusively establishes the thixotropic nature of sand-hydrate slurries

where the viscosity decay rate is directly influenced by the shear rate. These insights aim to contribute comprehensively to the development of effective flow assurance strategies

ensuring the safe and stable operation of subsea hydrate exploitation.