Rankin Chemical Technologies, Inc.
engineering · consulting · process design

Emergency Relief System Design

Rankin Chemical Technologies has acquired extensive experience in the evaluation and design of hundreds of emergency relief devices for a variety of chemical systems.  This expertise can be applied in your facility to ensure protection of critical assets with detailed documentation that can hold up under scrutiny from audits.  Some typical services provided with this work include the following:

  • Development of overpressure scenarios for chemical systems, including multi-component mixtures.
  • State-of-the-art sizing of rupture discs and pressure relief valves using latest methods from API Standards 520/521.
  • Hydraulic analyses of inlet piping and tailpipe systems for liquid, vapor and two-phase flows.  Calculation of critical flow velocities and pressures, and reaction forces at the PRD and pipe discharge point.
  • Determination and modeling of two-phase vapor+liquid relief events using DIERS technology with churn-turbulent, bubbly and homogeneous vessel flow models.  Sizing carried out using the homogeneous equilibrium flow model (HEM) with the well established two-point Omega method.
  • Rigorous time-dependent dynamic analysis of two-phase flow events from initiation of relief through disengagement to all-vapor flow.

Visit our site Rankin ERS Services for more detailed information related to this important topic.

To better appreciate the intricacies involved in the proper sizing of relief systems, an example pressure relief valve case is presented.

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