Introduction to Aspen Plus Topics Covered Starting Aspen Specifying Units (English, Metric, SI) Specifying Property Methods & Components Developing the Flowsheet and Adding Blocks Connecting and Renaming Streams / Blocks Next Button / Data Browser Determining the Proper Physical Property Methods Viewing Results (Model Summary, Report Options) These topics will be covered while illustrating Aspen Plus using an example

Example Problem 1 1500 lb/hr of a process stream at atmospheric pressure containing 0.10 mole fraction methanol, 0.35 n-butane and 0.55 n-hexane is blended with 500 lb/hr of n-pentane also at atmospheric pressure. Both streams are initially at 70 OF and after mixing are to be heated (cooled for part D) for use in a downstream process. Use the Peng Robinson Equation of State for the problem. Use a pump to pressurize the mixed feed from atmospheric pressure up to 60 psia.   Determine the brake power in HP required for the pump to pressurize the stream at 30% efficiency. Determine the brake power in HP required for the pump to pressurize the stream at 70% efficiency. Use the 70% efficient pump for the remaining parts of the example.

Determine the energy required in BTU/hr to heat the process stream to 130 F using a heater block.   Determine the energy required in BTU/hr to cool the process stream to 40 F using a heater block. Determine the energy required in BTU/hr to heat the process stream to its bubble point using a heater block. What is the bubble point temperature? Determine the energy required in BTU/hr to heat the process stream to its dew point using a heater block. What is the dew point temperature? What is the heat of vaporization for this fluid?

Determine the amount of 150 psia saturated steam in lb/hr needed to heat the process stream from 70 to 130 OF using a HEATX block and give the heat exchanger area (ft2). The steam used is to be condensed but not sub-cooled on the shell side of the exchanger. Assume a 5 psia drop in the process fluid across the exchanger tubes and a 3 psia drop across the shell for the steam.   Determine the amount of 150 psia saturated steam in lb/hr needed to heat the process stream from 70 to 130 OF using a HEATX block if the steam is allowed to be subcooled 50 F after condensing on the shell side of the exchanger. Also give the exchanger area (ft2). Again assume a 5 psia drop in the process fluid across the exchanger tubes and a 3 psia drop across the shell for the steam.

There are various physical property methods

Mole and mass fraction are not presented unless selected under report options

Additional properties can be displayed for streams that are not normally given. This requires defining a property set

After creating a property set it can be populated with various properties of interest. For example the molar heat capacity of the mixture (CPMX) and the mass heat capacity of the mixture (CPMX-M) with Units specified

Some properties may require the specification of a phase qualifier (e Some properties may require the specification of a phase qualifier (e.g. viscosity)

Once specified the property set needs to be added to the stream report in order to get the results

Some properties may require the specification of a phase qualifier (e Some properties may require the specification of a phase qualifier (e.g. viscosity)

To review results for the properties you can select report and display the streams