The Challenge
The client was storing reactive materials in vessels that could be subject to fire exposure. They wanted to be sure that the relief protection on the vessels was correctly sized, or if not, what changes were necessary for an
effective relief system.
Our Approach
Reactive systems present additional degrees of complexity. The reactive characteristics of the material should be well understood by the ERS designer, including the potential for reacting with itself, decomposing, rearranging, or reacting with contaminants such as water, air, rust, and other materials that could be present in the system. Also, all reactions that could occur should be identified, and the kinetics of these reactions should be determined either by experiment or through trusted literature sources. Lastly, the characteristics of the vessel contents must be known so that two-phase flow methods may be utilized as deemed appropriate.
Using
Process Safety Office® SuperChems™ and reaction kinetic data supplied by the client, ioMosaic performed dynamic simulations of the vessels and the relief valves containing the reactive materials. From the simulations, plots of the internal pressures and temperatures of the vessels were calculated. For some vessels, due to exposure to the heat input from the fire, the internal temperature could get high enough to cause a runaway reaction. For these vessels, additional dynamic simulations were conducted to determine the effects of adding fireproof insulation or increasing the relief valve size.
The Benefits
From the dynamic simulations made, ioMosaic was able to advise the client on the most economical approach to obtain an effective emergency relief system. The data on the client's existing pressure relief devices was collected and detailed electronic pressure relief valve reports were delivered for their PSM files using
Process Safety Enterprise® Emergency Relief System Design Workflow software.