Experimental investigation of induction time for double gas hydrate formation in the simultaneous presence of the PVP and L-Tyrosine as kinetic inhibitors in a mini flow loop apparatus

The main objective of the present work is experimental investigation of induction time for double gas hydrate formation in the presence or absence of kinetic inhibitors in a mini flow loop apparatus. For this purpose, a laboratory mini flow loop apparatus is designed and built up to measure the induction time for binary mixtures during gas hydrate formation when a gaseous mixture (such as 70% C1-30% C3, 30% C1-70% C3, 70% C1-30% i-C4 and 30% C1-70% i-C4) is contacted with water in the absence or presence of dissolved inhibitor, such as poly vinylpyrrolidone (PVP) and L-tyrosine under suitable temperature and pressure conditions. In each experiment, water blend saturated with gas mixture is circulated up to a required pressure. Pressure is maintained at a constant value during experimental runs by means of the required gas mixture make-up. In this work, induction time is investigated for of double gas hydrate formation in vitro in the presence of the PVP and L-Tyrosine alone and their simultaneous presence as kinetic inhibitors in a mini flow loop apparatus at various concentrations. The results show that the simultaneous addition of PVP and L-tyrosine increases the induction time of gas hydrate formation several times more than that without using the inhibitor. Indeed, the addition of the small value of L-tyrosine to PVP, the induction time being longer than when PVP is as a kinetic inhibitor only, because the L-tyrosine is stronger than the PVP as an inhibitor. (C) 2014 Elsevier B.V. All rights reserved.