Mathematical Modeling of Atmospheric Dispersion from Accidental Release of Ammonia (NH3) during Road Transport

Abstract

This work aimed to analyze the atmospheric dispersion of ammonia gas (NH3) caused by a hypothetical leak in a tanker truck due to an accident during its transport. These accidents with dangerous products in road transport are unpredictable and can generate severe impacts on communities' borders and the environment close to the accident site. With the use of mathematical models, it is possible to estimate, assuming that there was an accidental release, how far, from the point of leakage to the cloud formed in the atmosphere will move until it is diluted in a way that does not pose a danger of toxicity. In this work, the ALOHA software and Google Earth will be used to estimate the dispersion of this toxic gas in different scenarios, varying the stability class and the height of the leak orifice. Among the proposed and analyzed scenarios, the results show that the plume with the greatest reach was 948 m in the red zone (AEGL 3 - 1100 ppm or 769 mg/m3), 1900 meters in the orange zone (AEGL 2 - 160 ppm or 112 mg /m3) and 3600 meters in the yellow zone (AEGL 1 - 30 ppm or 21 mg/m3).