Methane hydrate dissociation from anti-agglomerants containing oil dominated dispersed systems

Abstract

In this work, methane hydrate dissociation has been systematically studied in consideration of anti-agglomerant type, water cut, and anti-agglomerant dosage. The anti-agglomerant was sorbitan monolaurate (Span 20), rhamnolipid, and (Span 20 + esters polymer), respectively. Water cut ranged from 5 vol% to 30 vol%, and dosage of anti-agglomerant ranged from 0.5 wt% to 3.0 wt%. The results suggested that Span 20 may act as a dissociated kinetic inhibitor to prevent methane hydrate from dissociation, while rhamnolipid may act as a dissociated kinetic promoter to improve methane hydrate dissociation. 3.0 wt% of Span 20 decreased the maximum dissociation rate to 0.006 mol/min at 5 vol% water cut, while 3.0 wt% of rhamnolipid increased maximum dissociation rate to 0.029 mol/min at 10 vol% water cut. Water cut not only affected the amount of dissociated methane hydrate, but also affected maximum dissociation rate. The increase of water cut obviously increased maximum dissociation rate, and the maximum dissociation rate can reach 0.043 mol/min.