PHASE ENVELOPE WITH CO2 FREEZING/ FROST CURVE CALCULATOR

Vapor liquid equilibrium software
Vapor liquid equilibrium software
Vapor liquid equilibrium software

Phase Envelope with CO2 Freezing Curve Calculator

Carbon dioxide (CO2) freezing and frost curve for a hydrocarbon mixture containing CO2 marks the section of pressure-temperature plot in which the hydrocarbon mixture containing CO2 exists in three phase solid-liquid-vapor (SLV) equilibrium. Phase envelope of a hydrocarbon mixture is generally a closed region on pressure temperature plot with bubble point curve on one side and hydrocarbon dew point curve on the other side and with bubble point and hydrocarbon dew point curve meeting at critical point of the hydrocarbon mixture. However for hydrocarbon mixtures containing carbon dioxide (CO2), at low pressure values, the hydrocarbon mixture exists in three phase  equilibrium instead of usual two phase vapor liquid equilibrium existing inside phase envelope. The third phase in equilibrium with vapor and liquid phase in this region of phase envelope is solid carbon dioxide or dry ice. The triple point of carbon dioxide is at around 5.18 bars pressure and 216.5 K temperature implying that carbon dioxide can not exist in liquid state below a pressure of 5.18 bars. At atmospheric pressure (=1.013 bars) and below 5.18 bars pressure, solid carbon dioxide also known as dry ice converts directly from solid state to gaseous state. This endothermic process of direct conversion of a solid to gas without transitioning into liquid is known as sublimation. Among the commonly known hydrocarbons and inorganic gases composing oil and natural gas mixtures, carbon dioxide has got the highest triple point. Although other hydrocarbons and inorganic gases composing oil and natural gas mixtures can also solidify but under cryogenic conditions, carbon dioxide solidifies at the highest pressure as its triple point pressure is the highest. Under cryogenic conditions, proper care should be taken to avoid solidification of gaseous carbon dioxide into dry ice as it may damage the handling equipment.

Accurate calculation of CO2 freezing and frost curve is very much desirable for all of the processes involving handling of hydrocarbon mixtures containing carbon dioxide under cryogenic conditions to avoid damage to handling equipment.

Phase envelope with CO2 freezing and frost curve 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 temperatures at increments of 0.4 bars throughout the phase envelope and phase envelope curve on pressure-temperature plot.

Equilibrium temperature, vapor and liquid compositions and molar fractions of vapor, liquid and dry ice (solid CO2) at pressure values throughout the carbon dioxide freezing and frost curve at increments of 0.4 bars.

CO2 freezing and frost temperatures at increments of 0.4 bars throughout the carbon dioxide freezing and frost curve and carbon dioxide freezing and frost curve on pressure-temperature plot.

Sample Result – Download

Calculation cost (with temperature dependent BIPs) : USD 100

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