Designing a Fluid Curtain System As an Independent Protection Layer

Fluid Curtains are an effective means of post-release mitigation, and are typically intended to dilute, disperse or neutralize toxic vapor cloud dispersions.

When designing a Fluid Curtain System, there are many parameters to consider with regards to the effectiveness and reliability of the system. Focusing on the system effectiveness, these parameters include spray and nozzle characteristics, fluid solubility, contact time, fluid flowrate, and orientation; as well as considering all the Loss Of Containment scenarios (LOCs) that require mitigation.

If the Fluid Curtain System is to be considered as an Independent Protection Layer (IPL), then it must be capable of preventing a LOC from proceeding to the undesired consequence without being adversely affected by the initiating event, or the action of any other protection layer associated with the scenario. Applying this concept to the Fluid Curtain System design, it must guarantee a sufficient level of reliability, typically expressed by Safety Integrity Level (SIL).

This paper discusses the steps and requirements involved in designing a Fluid Curtain System, and the additional effort required to ensure it functions as an IPL.