Consequences analysis of a natural gas pipeline: The case of the trans-Anatolian natural gas pipeline

Industrial accidents include fire, explosion, and toxic substance spread involving hazardous substances. They threaten the health of many people, cause permanent or long-term pollution of the natural environment, cause a high degree of property damage, and require a large-scale emergency response. Pipelines that transfer hazardous chemicals over a large area are risky for industrial accidents. In this study, we aimed to analyze the consequences of a possible industrial accident at the Edirne Ipsala compressor station in the trans-Anatolian natural gas pipeline (TANAP). Analyses were carried out with the ALOHA software on two hypothetical scenarios: In Scenario 1, the chemical escapes from the pipe without the gas burning; and in Scenario 2, the chemical escapes from the pipe with the gas burning (jet fire). In the analysis of overpressure effects, TNT EM and TNO MEM were used besides the software. The largest effect distance (≈5000 m) was determined in the flammable area as a result of Scenario 1, and the prominent hazard property of the chemical was supported. The overpressure effects obtained with TNO MEM and the software were compatible with each other, but the values obtained with TNT EM were less severe and quite different. In the analysis of overpressure effects, it is shown that the ALOHA software provided more conservative results and that buildings would collapse and lethal effects might occur at a distance of 1000 m from the source. ALOHA produced outputs integrated with GIS by providing thermal radiation and toxic effect threat zones as well as overpressure effects. ALOHA turns out to be a more convenient and practical tool for risk assessment studies and emergency plans.