CARBON-DIOXIDE HYDRATE EQUILIBRIUM CONDITIONS IN AQUEOUS-SOLUTIONS CONTAINING ELECTROLYTES AND METHANOL USING A NEW APPARATUS

A knowledge of the gas hydrate formation conditions, i.e., pressure, t emperature, and compositions, of the coexisting phases at equilibrium, is required in formulating processes to avoid their formation in natu ral gas transmission lines or processing equipment. Additives like met hanol and electrolytes are often used to inhibit hydrate formation in industrial ope:rations. Computation of the inhibition effects of these additives is necessary for the design. of such operations. Developmen t of thermodynamic methods to calculate the hydrate equilibria conditi ons requires accurate experimental data. In the present work experimen tal three-phase (aqueous liquid solution, vapor, and incipient hydrate ) equilibrium conditions of CO2 hydrate formation in aqueous solutions of electrolytes and methanol are measured in the temperature range of 263-279 K and pressure range of 0.9-3.0 MPa. A new ''full view'' sapp hire tube equilibrium cell and the associated equipment are designed, fabricated, and used for the measurements. The equipment details and t he measured data are also reported here.