F(HCFC-141b)hydrate in pipelines were conducted in a newly built flow loop with a diameter of 42 mm and length of 30 m. The results show that there are two kinds of hydrate structures in the pipeline
slurrylike hydrates and slushlike hydrates
with superfluous water in the pipeline and the transition from slurrylike hydrates to slushlike hydrates occurred when the hydrate volume fraction is from 30% to 40%. Diameters of the hydrate particles in the pipeline are mainly from 154 μm to 450 μm and the average diameter of the hydrate particles increases with the increase of the hydrate volume fraction. Moreover
the pipeline is completely blocked with the hydrate when the hydrate volume fraction in the pipeline reaches
70%. In addition
the hydrates aggregate quickly with the increase of the hydrate volume fraction when slushlike hydrates occur
which can result in blockage in the whole pipeline.
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references
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