Identification of a New Experimental Method to Measure the Induction Time for Gas Hydrates

Abstract

- The gas hydrate formation process is divided in two main phases: the initial nucleation and the following massive growth phase. The time required for the production of a quantifiable quantity of hydrates is referred as “induction time”. Different solutions have been proposed to measure this interval; however, the low accuracy of the measure and the difficulties in evaluating it in the medium – scale lab reactors, have been not still solved. The most diffused technique consists of the visual confirmation of the production of a numerable quantity. In this work, a new alternative approach was proposed and experimentally validated. Being the formation process exothermic, the formation of the target quantity of hydrates leads to the appearance of peaks in temperature in a confined environment. These peaks cannot be exploited, due to their casual occurrence, associated to the stochastic nature of the process. Differently, the quantity of heat produced, can be directly used to calculate the moles of hydrates formed; thus, it allows to characterize the induction period for the process. In this research, the induction time was evaluated during the formation of methane and carbon dioxide hydrates, in order to detect any potential difference between the two species .