A model for estimating flow assurance of hydrate slurry in pipelines

The problem of hydrate blockage of pipelines in offshore production is becoming ever-increasing severe because oil fields in ever-increasing unusual environments have been brought in production. HCFC-141b and THF were selected as the substitutes to study the flow assurance of the hydrates in pipelines. There are critical hydrate volume concentrations for these two slurries. Hydrate slurries behave like Bingham fluids and have high agglomerating tendency when the hydrate volume concentrations are larger than the critical ones. Based on rheological behaviors of these two hydrates, a non-dimensional parameter is proposed through studying the driving forces of agglomeration among hydrate particles, which shows the agglomerating probability of hydrate particles in pipeline and can be used to judge the safety of the pipeline. Moreover, a safe model to judge the safely flow hydrate slurries was presented and verified with the experimental data, which demonstrates that the model is effective to judge whether the pipeline can be run safely or not.