Aspen property method
Thread Content
There is an existing ethanol solution that contains some sodium chloride in it. What property methods should be used for ethanol distillation simulation? Using only the NRTL equation presents many problems. The feed rate is about 6,000 kg/h; it contains 45% ethanol and around 5% sodium chloride. The required ethanol concentration at the top of the tower is 92%, while it should be 1% at the bottom of the tower. Please provide guidance.
The presence of sodium salts may affect the physical properties of ethanol solutions; therefore, when simulating ethanol distillation, other methods for determining physical properties can be considered, such as using UNIFAC or ASOG for calculations. Furthermore, some appropriate measures must be taken during the separation process, such as the addition of chemicals or the use of special tray structures, to improve separation efficiency. It is recommended that you seek the help of professional chemical companies or engineers to obtain more accurate results. .
Is it to design a tower, or to calculate the operating parameters of an existing tower?
It is necessary to design a tower; the direct NRTL module cannot perform complete calculations
Try the UN… type material property scheme.
Then just use Uniquac for the calculation; the results obtained should be fine for use in design. The main reason is that, in theory, salt can increase the distance between the y and x axes, making separation easier, whereas the built-in Uniquac calculation is somewhat conservative.