Effectiveness of water spray mitigation systems for accidental releases of hydrogen fluoride

Abstract

Accidental releases of pressurized, superheated hydrogen fluoride (HF) can result in initially dense clouds which will typically contain a mixture of HF vapor, aerosol, and droplets. Previous experiments were performed by Amoco Oil Company and Lawrence Livermore National Laboratories (the Goldfish series in 1986) to study atmospheric dispersion of these HF clouds. The present study examines the effect of water application on the mitigation of these clouds. To assess the effectiveness of water application (via either sprays or monitor) in mitigating HF clouds two series of tests were conducted in separate flow chambers. Bench scale experiments identified key variables for testing in a larger facility. The larger scale field tests demonstrated that HF releases can be mitigated with water. The impact of numerous design variables on mitigation effectiveness has also been quantified. HF removal efficiencies of 25 to 90+% have been demonstrated at water to HF liquid ratios of 6/1 to 40/1 and higher. 6 refs., 22 figs., 2 tabs.