Quantitative Risk Assessment of City Gas Distribution Networks in India: Enhancing Safety with PHAST Modeling

Abstract

City Gas Distribution (CGD) networks in India have evolved remarkably since their inception in the 1960s and 1970s, expanding from their initial industrial use in metropolitan areas like Mumbai, Delhi, Surat, Indore, and Mathura to serve domestic, commercial, and industrial consumers across multiple cities. This paper presents a comprehensive Quantitative Risk Assessment (QRA) of CGD networks in Indian cities, emphasizing safety, reliability, and sustainability. The scope includes a QRA of all existing infrastructures and facilities within the geographical areas of each CGD network. By analyzing historical incident data and utilizing advanced modeling techniques, potential hazards are identified, their probabilities estimated, and their consequences evaluated. The study highlights the critical importance of implementing robust risk mitigation measures to enhance the safety and reliability of CGD networks, ensuring sustainable urban energy distribution. Additionally, the integration of eco-friendly fuels like compressed biogas and LNG is addressed, underscoring the need for continuous improvement in risk management practices. Risk assessments were conducted using PHAST-8.22 software, and risk reduction measures were proposed based on the assessed risk levels. The adopted methodology includes the study of pipeline and terminal operations, examination of operating parameters, hazard identification, probability-based risk analysis, and the formulation of risk reduction strategies.