Development of an automated, high pressure heat flux calorimeter and its application to measure the heat of dissociation and hydrate numbers of methane hydrate

Abstract This report presents the results of an experimental program to develop a generalized heat flux Calvet calorimeter, modeled after its Mraw-Kleppa (1984) modification,to study the calorimetry of a gas hydrate under free surface and porous media environments. The calorimeter features an aqueous phase electrical conductivity tracking system, and computerized data acquisition and control for both isothermal and isobaric operations. The resulting average heats of dissociation for methane are 58071 J mol−1 ±2.6% at 278.15 K and 53235 J mol−1 ±2.6% at 283.15 K. The respective averaged occupation numbers are 5.97 and 5.98. The data of this study adjusted to 273.15 K are 6–7% higher than those reported by Handa (1986) and by Rueff (1988). The automated nature of the calorimeter allows unattended operation after the initial charging and hydrate formation process have been carefully conducted. Several qualitatively different kinds of experiments for the calorimeter have recently been proposed.

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