Risk of Fire and Explosion in Electrical Substations Due to the Formation of Flammable Mixtures.
Ontology highlight
ABSTRACT: Transformers reduce the voltage from overhead powerlines to voltages acceptable for city/neighbourhood needs. Overheating of transformer cooling fluids presents a serious hazard. In this work, the risk of fires and explosions due to vaporisation of the hydrocarbon components of mineral oil, which is used as a transformer cooling fluid in electrical substations, was investigated. The compositions of new and used mineral oil from an electrical substation in Riyadh were analysed using gas chromatography-mass spectrometry, and C6 to C41 hydrocarbons were detected. The majority of the components were alkanes, alkenes, or alkynes; some ketone, alcohol, aromatic, and anhydride species were also detected. Approximately 25% of the compounds comprising the new oil sample were alkanes, whereas more than 33% of the used oil sample components were alkanes. The lower and upper flammability limits (LFL and UFL) of the mixtures were found to be 0.88 and 5.75 vol.% for the new oil and 0.47 and 3.05 vol.% for the used oil, respectively. These values were used to construct a flammability diagram. The results indicated that the new and used oil vapour mixtures were not flammable at 25?°C and 1?atm, but would become flammable at 77 and 115?°C.
SUBMITTER: El-Harbawi M
PROVIDER: S-EPMC7156400 | biostudies-literature | 2020 Apr
REPOSITORIES: biostudies-literature
ACCESS DATA