The analytical isothermal cell is used for the purpose of measurement of multi-phase equilibria in hydrocarbon-water-hydrate inhibitor systems, but can be apllied to other similar systems.
The main part of the apparatus is the variable-volume high-pressure equilibrium cell, specially designed for this application and equippede with a 360° sapphire window. The volume of the cell can be varied manually and automatically by means of a high pressure syringe pump. The temperature, measured in different points of the cell by platinum resistance thermometers, is monitored and recorded over time through a computer.
Connected to the cell are three automatic ROLSITM (Rapid On-Line Sampler-Injector) sampler-injectors, which allow for the withdrawing of very small samples from the different phases directly to the carrier gas stream of a gas chromatograph (GC), where the samples are then analysed.
The current analysis is done using an Agilent 6890 GC system, equipped with an Agilent 7683B automatic injector, a HP-PLOT Q capillary column, and a thermal conductivity detector (TCD) coupled in series with a flame ionisation detector (FID). For acquisition and treatment of the GC data, a computer installed with the software GC ChemStation (Agilent Technologies, Inc., USA) is used.
The analytical isothermal cell is used for the purpose of measurement of multi-phase equilibria in hydrocarbon-water-hydrate inhibitor systems, but can be apllied to other similar systems.
The main part of the apparatus is the variable-volume high-pressure equilibrium cell, specially designed for this application and equippede with a 360° sapphire window. The volume of the cell can be varied manually and automatically by means of a high pressure syringe pump. The temperature, measured in different points of the cell by platinum resistance thermometers, is monitored and recorded over time through a computer.
Connected to the cell are three automatic ROLSITM (Rapid On-Line Sampler-Injector) sampler-injectors, which allow for the withdrawing of very small samples from the different phases directly to the carrier gas stream of a gas chromatograph (GC), where the samples are then analysed.
The current analysis is done using an Agilent 6890 GC system, equipped with an Agilent 7683B automatic injector, a HP-PLOT Q capillary column, and a thermal conductivity detector (TCD) coupled in series with a flame ionisation detector (FID). For acquisition and treatment of the GC data, a computer installed with the software GC ChemStation (Agilent Technologies, Inc., USA) is used.
Publications
José M.S. Fonseca and Nicolas von Solms, “Development and testing of a new apparatus for the measurement of high-pressure low-temperature phase equilibria,” Fluid Phase Equilib. 329, 55 (2012).