Investigations into the distribution of hydrocarbon concentrations in underground tanks of petrol stations

• Published in: Journal of hazardous materials 1995, Vol.42 (1), p.1-14
• Main Author: Frobese, Dirk-Hans
• Format: Article
• Language: English
• Subjects: Air; Applied sciences; Crude oil, natural gas and petroleum products; Crude petroleum; Energy; Evaporation; Exact sciences and technology; Fuels; Laws and legislation; Oil tanks; Oil terminals; Soils; Transportation and distribution of crude oils and liquid petroleum products. Ships. Pipelines. Terminals. Service stations
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/0304-3894(94)00102-M

Underground tanks in petrol stations for the storage of petrol need not be equipped with flame-arresting devices provided some conditions stipulated in the relevant technical rules are met. These conditions are to ensure that the gas atmosphere in storage tanks is always overrich. Investigations carried out in an arrangement of tanks corresponding to the practice showed that the air entering the tank during the delivery of petrol leads to a dilution of the gas atmosphere in the tank and that the upper explosion limit is not reached in partial volumes. These partial volumes are thus explosive. The extent of the explosive partial volumes essentially depends on the impulse associated with the inflowing air. The greater this impulse, the stronger the evaporation of petrol and the smaller the explosive partial volume to be expected. The limitation of the delivery rate to 2001/min as required in the Technische Regeln für brennbare Flüssigkeiten (TRbF, Technical rules for flammable liquids) [4] is therefore an unsuitable criterion to ensure an overrich tank atmosphere.