FlowPhase Examples Page 1 of 15. Table of Contents

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1 FlowPhase Examples Page 1 of 15 Table of Contents 1. VLE Flash Basic Input Entering Components Entering mol fractions Performing a flash Changing Units Exporting data to Excel Additional Features K Factors, Component mol fractions in vapor/liquid phases Heating Contents, Wobbe Index and Liquid Content Rate and Sizing Calculator Phase Envelope Temperature Drop Across a Valve... 14

2 FlowPhase Examples Page 2 of VLE Flash 1.1 Basic Input Suppose you want to know the conditions of a stream with the following characteristics: Component Mol% N CO H2S Methane Ethane Propane i-butane n-butane i-pentane n-pentane Hexane Heptane At 10 F and 400 PSIA Start VLEFlash which will give the following screen at left: In the pull down box Initial Conditions, a menu of options will be found similar to the screen on the right above. Select Temperature Pressure Flash. Filling in the temperature and pressure, the units can be selected from either Field or SI equivalents.

3 FlowPhase Examples Page 3 of Entering Components Selecting Component brings up a sub-menu shown at the left below. Choosing from a list of possible components, as the entries are highlighted, they are automatically inserted under the Input Stream. 1.3 Entering mol fractions Next, we need to insert the component breakdown. Here, we can enter the mol fractions: Oops, we really need mol%. No problem, just hit Normalize and the program computes the entries on a 100% basis as shown at right.

4 FlowPhase Examples Page 4 of Performing a flash Now, we are ready to perform a flash. Simply click and enter on Execute Flash and the following screen leaps into view: 1.5 Changing Units Notice that the output values are in SI. No problem, simply go to the drop down menu Units and select US. Field Units (or use the Ctrl+M hotkey). The equivalent field units will replace the calculated SI values. Individual results may be converted to a variety of units by clicking on the appropriate units drop down boxes and selecting the available choices. Note that changing the initial temperature or pressure values, or changing the units they were initialized in will make the results box disappear and will necessitate re-executing the flash.

5 FlowPhase Examples Page 5 of Exporting data to Excel The results can be printed directly to a printer or exported to an Excel spreadsheet: Excel will be started and the values inserted into a blank sheet. Note that you may wish to do some additional formatting on the values and column widths.

6 FlowPhase Examples Page 6 of Additional Features K Factors, Component mol fractions in vapor/liquid phases Using the Composition button can be selected to show a mol fraction of components in the vapor or liquid states, along with the corresponding K factors:

7 FlowPhase Examples Page 7 of Heating Contents, Wobbe Index and Liquid Content These parameters may be accessed by selecting the More Properties button. Yields:

8 FlowPhase Examples Page 8 of 15 Further information may be obtained by selecting the Liquid Detail button: The Liquid Content is the amount of propane plus components in the gas stream converted to liquid by molar calculation. This number has nothing to do with a real flash calculation but is often shown on laboratory analyses to help reservoir engineers estimate recoverable liquids.

9 FlowPhase Examples Page 9 of Rate and Sizing Calculator Often, the Engineer knows a feed rate and wants to extimate how much liquid will be produced at a separator. Press Rate Calc. Yields: From this panel, a flow rate may be entered.

10 FlowPhase Examples Page 10 of 15 In this example, sizing is based on 10 MMSCFD Notice you also get some quick rules of thumb type sizing information for pipe ID required at 2 psi/100 ft pressure drop, mesh pad diameter for a vertical separator and a bubble cap tray for a dehydrator. Further information regarding the mesh pad, line sizing basis may be called up by selecting Info :

11 FlowPhase Examples Page 11 of Phase Envelope A Pressure/ Temperature phase envelope of the input stream may be printed/viewed by selecting Charts and highlighting Phase Envelope. which will yield the following for the example stream:

12 FlowPhase Examples Page 12 of Format Options Noted from the above screen is a single pull-down menu Format. A variety of items may be selected: Included are options for changing line colours, of which the dew point curve has been altered from magenta to red in the screen above. Various units of Temperature and Pressure may be selected as well as changing the range over which the phase envelope is presented. The Grid may be shown as in the example, or switched off. The critical point is marked on the graph, however further format selections allow a numerical print-out which is superimposed on the graph. In the example above, Critical Point is highlighted which yields the following:

13 FlowPhase Examples Page 13 of Vapor Compositional Line(s) Various percentages of vapor may be superimposed on the Phase Envelope graph by selecting Vapor Compositional Line. A few examples have been generated for 95, 90 and 80% vapor. The graph may be saved or printed.

14 FlowPhase Examples Page 14 of Temperature Drop Across a Valve Calculation is a two step process, where a feed stream is flashed (as in the previous examples). The enthalpy is automatically calculated and used to flash the stream at a different (lower) pressure using the Pressure-Enthalpy Flash. Note the units for Enthalpy have been changed to BTU/lb-mol for illustration purposes. The flash method has been poised on the Pressure Enthalpy Flash method. Selection of the flash method will yield the screen as illustrated. Note that the enthalpy has been carried over in the corresponding Enthalpy box. From here, simply adjust the pressure for an estimate of the conditions downstream of the valve, noting that a valve is a constant enthalpy device.

15 FlowPhase Examples Page 15 of 15 Finally, perform Execute Flash to yield the following results: It can be noted that the temperature has decreased to 57.4 F which is an indication that cold temp steel would be a requirement, for example, if the contents were flashed down into a flare header.