Project Synopsis
Perform a dispersion modeling analysis for a hypothetical LPG pipeline rupture scenario involving a pipeline in Louisiana.
Project Summary
The client, an environmental services provider working for a pipeline operating company, subcontracted Process Engineering Associates, LLC (PROCESS) to perform a dispersion modeling analysis for a hypothetical pipeline rupture scenario involving a pipeline in Louisiana.
The dispersion modeling was conducted using DNV’s Phast Dispersion Modeling Software and evaluated the release of three Liquefied Petroleum Gases (LPGs): propane, n-butane, and iso-butane.
The analysis produced a variety of outputs, including 2D side-view dispersion plots (cloud height versus distance downwind) and maximum cloud footprint graphs (cloud width versus distance downwind). The study focused on both toxic exposure thresholds—specifically Immediately Dangerous to Life or Health (IDLH) levels—and flammability risks, based on the Lower Explosive Limit (LEL).
The scenario’s model assumed a full-bore pipe rupture during pipeline transfer operations, continuing until emergency shut-off valves were fully closed and pump stations were isolated. Multiple atmospheric conditions and Pasquill stability classes were incorporated to ensure a conservative modeling approach.
This scope of work resulted in the following project deliverables:
- Contour plots of key concentration thresholds, as defined by the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA).
- A comprehensive Project Presentation Report, detailing the design basis, modeling methodology, and key dispersion modeling outputs generated using DNV’s Phast software.
- A comparative analysis of the maximum downwind hazard distances under varying wind and weather conditions, across the different LPG product compositions.
With safety as the principal priority, the dispersion modeling results and reporting provided by PROCESS offered the technical detail necessary to support data-driven decision-making for High Consequence Area (HCA) identification and pipeline risk management, helping to ensure the protection of public health and welfare.
Industry Type
Downstream Oil & Gas Pipeline Operations
Utilized Skills
- Dispersion modeling.