# Phase Envelope Calculator

Phase envelope software / phase envelope calculator uses Peng-Robinson cubic equation of state for phase envelope calculation for oil and natural gas / multicomponent hydrocarbon mixtures.

Phase envelope of a hydrocarbon mixture is the phase transition curve on a pressure temperature plot. The hydrocarbon mixture exists in two phases or partly in liquid phase and partly in vapor phase inside the phase envelope. However the hydrocarbon mixture is either completely in liquid phase or completely in vapor phase outside the phase envelope. The phase envelope consists of a bubble point curve and a hydrocarbon dew point curve. The point on the phase envelope where bubble point curve and hydrocarbon dew point curve meet is known as critical point. The region on a pressure temperature plot above and to the right side of the critical point is known as critical region. In the critical region of a hydrocarbon mixture, the hydrocarbon mixture cannot be distinguished as liquid phase or vapor phase. The point of maximum pressure on the phase envelope is known as cricondenbar whereas the point of maximum temperature on the phase envelope is known as cricondentherm. Generally the phase envelope of a hydrocarbon mixture is a closed region on pressure temperature plot. However for hydrocarbon mixtures consisting of components widely different in size and volatility, the phase envelope can be an open region.

Accurate calculation of phase envelope is very much desirable for all of the processes involving separation of hydrocarbons like distillation and flashing. Also accurate calculation of critical point, cricondenbar and cricondentherm is very much important in characterization of hydrocarbon mixtures. Critical point, cricondenbar and cricondentherm in particular and phase envelope in general are very much important in simulation of oil and gas wells.

Phase envelope software / Phase envelope calculator from EQ-COMP can calculate accurate phase envelopes for any mixture of nonpolar or mildly polar hydrocarbons and inorganic gases. Phase envelope calculation module can calculate open phase transition curves for hydrocarbon mixtures with substantial amounts on non-condensables apart from closed phase envelopes for natural gas mixtures. Phase envelope calculator from EQ-COMP can include constant, user defined and temperature dependent binary interaction parameters (BIPs) in its calculations.

Phase envelope software / phase envelope calculator from EQ-COMP calculates

Critical point temperature and pressure and compositions, K values, liquid and vapour compressibility factor values, liquid and vapour densities and liquid and vapour molecular weight at critical point as per bubble point curve.

Equilibrium temperature, compositions, K values and compressibility factor values at pressure values throughout the bubble point curve at increments of 0.4 bars.

Critical point temperature and pressure and compositions, K values, liquid and vapour compressibility factor values, liquid and vapour densities and liquid and vapour molecular weight at critical point as per hydrocarbon dew point curve.

Equilibrium temperature, compositions, K values and compressibility factor values at pressure values throughout the hydrocarbon dew point curve at increments of 0.4 bars.

Phase envelope temperature at increments of 0.4 bars throughout the phase envelope and phase envelope curve.

**Sample Result** – Download

**Calculation cost (without Binary Interaction Parameters) : USD 25
Calculation cost (with constant or user defined BIPs) : USD 100**

For requesting results of phase envelope software / phase envelope calculator and other modules, visit VLE CALCULATOR page