Building the Model in Aspen HYSYS

This section documents some of the key steps required to model the representative crude unit described in the previous section. We use a 50%-50% mixture of the assays presented in Table 2.5 to Table 2.8 as the feed to the column. In the workshop examples accompanying this chapter, we will simulate this column on the basis of back-blending alone and compare the results. 

Asseji I Cut/Blend User Property ] Corfelatior Install Oi T 

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At this point, we can return to the main flowsheet to complete building the model. Before leaving the basis environment Aspen HYSYS asks if we should hold the solver as shown in Figure 2.65. We recommend holding the solver until all changes in the process flowsheet are complete. This prevents erroneous solutions in the feed vaporization loop. 

This work represents the workflow to build an integrated HCR process model using Aspen HYSYS Petroleum Refining and routine measurement in refinery. 

A related problem is the conversion of kinetic lumps back to fractionation lumps required to build rigorous fractionation models. For our models. Aspen HYSYS gives a method to transition the kinetic lumps to pseudocomponents based on boiling points typically used to model the petroleum fractionation. We also propose an alternative technique that can provide similar results using methods developed in earlier in this section. Essentially, we must convert the kinetic lumps back into a TBP curve. The key steps in converting the kinetic lumps to pseudocomponents based on boiling point are ... 

The initial flowsheet presents a blank interface where we can place different objects from the Object palette shown in Figure 4.48. The initial tool palette only shows typical unit operations anddoesnot show the advanced Aspen HYSYS Petroleum Refining objects. We will use both toolbars to build the complete FCC model. We can bring up the advanced palette by pressing F6. 

Figure 4.72 shows the converged FCC unit operation window after Aspen HYSYS has successfully solved the model. We connect an effluent stream by bringing up the Connections section of the Design Tab and typing in Effluent for the Reactor Effluent stream. A stream titled Effluent will appear on the FED and we can use this stream to build further downstream fractionation units. 

In the following workshops, we demonstrate how to organize data, build and calibrate a model for a catalytic reformer using Aspen HYSYS Petroleum Refining. We discuss some key issues in model development and how to estimate missing data required by Aspen HYSYS Petroleum Refining. We divide this task into four workshops ... 

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