Dynamics mode results for the CC2 example simulation

We developed a set of six scenarios in line with the publication by Luyben2 to test the control scheme against the following disturbances:

• Increase the C3 fresh feed from 4600 kg/h to 5200 kg/h.

• Decrease the C3 fresh feed from 4600 kg/h to 4200 kg/h.

• Increase the setpoint of the reactor outlet temperature controller from 350°C to 355°C.

• Decrease the setpoint of the reactor outlet temperature controller from 350°C to 345°C.

• Increase the propylene composition in the C3 fresh feed to 97%.

• Decrease the propylene composition in the C3 fresh feed to 93%.

We composed an additional scenario to run all of the preceding scenarios sequentially and save each scenario’s history to an individual snapshot for review.

We have arranged a series of trend charts with an overview on the following aspects:

• Reactor outlet temperature

• Fresh feed rates, recycle rate, and cumene rate in the reactor outlet

• All liquid levels in the process

• All pressures in the process

• All heat duties in the process

• Benzene column performance

• Cumene column performance

We recommend that you:

• Select the Solve to Steady State button either at the end of a scenario or after stopping it prematurely, and then run the simulation for another 10 minutes to observe where the process stabilizes.

• Run at higher time steps, for example, 1 sec or greater, and compare performance.

Overall, the process stabilizes for each of the preceding 6 scenarios, as shown by the following trend charts for the reactor outlet temperature, the feed rate, and the recycle rate:

Figure 8: Results for the scenarios to increase and decrease C3 feed from 4600 kg/h to 5200 kg/h and 4200 kg/h, respectively

Figure 9: Results for the scenarios to increase and decrease SP of reactor outlet TC from 350°C to 355°C and 345°C, respectively

Figure 10: Results for the scenarios to increase and decrease propylene composition in C3 fresh feed to 97% and 93%, respectively