Investigation of the Flow Characteristics of Methane Hydrate Slurries with Low Flow RatesReport as inadecuate


Investigation of the Flow Characteristics of Methane Hydrate Slurries with Low Flow Rates


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Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China

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CAS Key Laboratory of Gas Hydrate, Guangzhou 510640, China

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Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China

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Guangzhou Center for Gas Hydrate Research, Chinese Academy of Sciences, Guangzhou 510640, China





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Academic Editors: Enrico Sciubba and Alireza Bahadori

Abstract Gas hydrate blockage in pipelines during offshore production becomes a major problem with increasing water depth. In this work, a series of experiments on gas hydrate formation in a flow loop was performed with low flow rates of 0.33, 0.66, and 0.88 m-s; the effects of the initial subcooling, flow rate, pressure, and morphology were investigated for methane hydrate formation in the flow loop. The results indicate that the differential pressure drop ΔP across two ends of the horizontal straight pipe increases with increasing hydrate concentration at the early stage of gas hydrate formation. When the flow rates of hydrate fluid are low, the higher the subcooling is, the faster the transition of the hydrates macrostructures. Gas hydrates can agglomerate, and sludge hydrates appear at subcoolings of 6.5 and 8.5 °C. The difference between the ΔP values at different flow rates is small, and there is no obvious influence of the flow rates on ΔP. Three hydrate macrostructures were observed: slurry-like, sludge-like, and their transition. When the initial pressure is 8.0 MPa, large methane hydrate blockages appear at the gas hydrate concentration of approximately 7%. Based on the gas–liquid two-phase flow model, a correlation between the gas hydrate concentration and the value of ΔP is also presented. These results can enrich the kinetic data of gas hydrate formation and agglomeration and provide guidance for oil and gas transportation in pipelines. View Full-Text

Keywords: natural gas; hydrate; flow assurance; slurry; sludge; flow characteristics natural gas; hydrate; flow assurance; slurry; sludge; flow characteristics





Author: Cuiping Tang 1,2,3,4, Xiangyong Zhao 1,2,3,4, Dongliang Li 1,2,3,4, Yong He 1,2,3,4, Xiaodong Shen 1,2,3,4 and Deqing Liang 1,2,3,4,*

Source: http://mdpi.com/



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