Modification of Katz diagrams in allowable pressure drop across a throttle valve for avoiding gas hydrate formation

One of the first and easiest ways to determine the equilibrium conditions of hydrate formation for gas mixtures is gas gravity method presented by Katz. In addition, based on this fact that pressure depression in a throttle valve is a constant enthalpy process and so the temperature decreases when the pressure of the natural gas decreases, Katz presented a series of curves to estimate the maximum allowable pressure drop before gas hydrate formation.
In this communication, the van der Waals and Platteeuw solid solution theory has been used for predicting of hydrate formation conditions. Moreover, using the Peng Robinson equation of state to predict the enthalpy of natural gas in the inlet and outlet streams of throttling valve, the maximum allowable pressure drop curves, have been reproduced. Finally, results of this work have been compared with the Katz curves for maximum allowable pressure drop.