A Medium-Scale Cryogenic Spill Study to Estimate Vapor Formation on Concrete Substrate
Abstract
This paper presents the findings of medium-scale (5 - 15 kg) cryogenic liquid experiments on a concrete substrate which may represent an industrial grade diking material. The temperature varying thermal characteristics, i.e. the conductivity (k) and heat capacity (Cp) of the concrete substrate were measured in the range of -160°C to 50°C using guarded hot plate and DSC, respectively. Vaporization rate of liquid nitrogen (LN2), liquid oxygen (LO2) and a mixture of 80% LN2 and 20% LO2, (i.e. liquid air) were studied on the same concrete substrate. It was found that conductive heat transfer from the concrete substrate has the greatest contribution in the vaporization of cryogenic liquids. The evidence of phase change from film boiling to nucleate boiling was observed during the pool vaporization of LO2. The effect of preferential boiling on the temperature and heat flux profiles inside the concrete substrate was also observed. The change of heat fluxes due to the preferential boiling after each refill of mixture liquids were found to vary from 3% to 15%. Finally, the recorded heat flux during the early and later stages of pool vaporization were 12.4 kW/m2 and 3.7 kW/m2 for LN2 and 12.9 kW/m2 and 2.96 kW/m2 for LO2.
Description
PresentationSubject
Vapor Formation on ConcreteCollections
Citation
Ahmmad, Monir; Quraishy, Syed; Olewski, Tomasz; Mannan, Sam; Véchot, Luc (2016). A Medium-Scale Cryogenic Spill Study to Estimate Vapor Formation on Concrete Substrate. Mary Kay O'Connor Process Safety Center; Texas &M University. Libraries. Available electronically from https : / /hdl .handle .net /1969 .1 /193627.