3D. Liquid Density by COSTALD (Hankinson-Thomson) Method Back to Main

This page is used to determine the density of liquid using the Hankinson-Brobst-Thomason method (COSTALD). For pure components, it employs the basic equation: (Equation 3.22), which is the COSTALD density correlation.

Where: = molar volume of saturated liquid

= an empirical constant similar to in equation 3.20

It is typically with in 1 to 4% of

= SRK acentric factor

and = reduced volume factors which depend on

This equation is also applicable for mixtures using mixing rules to determine n * and . For liquid of known composition, the COSTALD methods is probably the most general and most accurate. For crude oils and condensates Density – Temperature Correlation for Liquids (Figure 3.11) and Relative Density of Hydrocarbon Mixtures (Figure 3.12) provides acceptable results for engineering calculations.

To calculate the liquid density the Temperature, Pressure, and Mole % of the Liquid must be entered into their entry spaces. Once this has been done, select Run to execute the solution.

The component table is a list of the possible compounds along with their symbols to be used with this program. In the far right column titled Mole % use the mouse to choose the available cell and enter the Mole % of each component in the mixture. Use the Up and Down arrow keys to move from cell to cell. The total for the Mole % should be 100.00.

Temperature is the temperature of the Liquid in SI units Celsius and Kelvin or in English units Fahrenheit and Rankin.

° C = 0.556 (° F - 32), K = ° C + 273, ° F = (1.8)(° C) + 32, ° R = ° F + 460

Pressure is the force exerted per unit area of the liquid. For engineering purposes, absolute pressure is used.

To convert unit values of data, please refer to “Set Auto Convert and Unit Conversion” in the main page.

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