Summary for the CC3 example simulation

Conventional methods (like the unbalanced heat method) that calculate column relief loads are generally conservative. This leads to overly-sized relief devices and flare networks. Alternatively, we can use dynamic simulation to accurately predict the transient pressure increase. According to API 5211, section 4.3.3, dynamic simulation is an accepted way to calculate column relief loads.

This example demonstrates how you can use AVEVA Process Simulation to quickly build dynamic simulations for column relief. We use AVEVA Process Simulation's modeling capabilities to make customizations that reflect the API 521 guidelines for relief estimation.

The objectives of this example are to:

• Build a column simulation that reflects the pressure relief guidelines in API 521.

• Identify the peak relief flow for the following scenarios:

  • Partial power failure

  • Total power failure

The following figure illustrates the benzene column simulation that we use for the relief study in AVEVA Process Simulation.

Figure 1: Benzene column simulation