Study of key properties of expansion foam for process safety incident mitigation using an improved foam generator

Expansion foam is a type of aqueous foam that is widely used for mitigating process safety incident, i.e., suppressing vapor dispersion, controlling fire and decontaminating chemical release. High expansion foam has a high volumetric ratio of air to liquid, from 200 up to around 1,000, making it effective in controlling fires in confined spaces and mitigating the hazards of cryogenic releases. Previous studies have investigated foam expansion ratio and foam stability using a research foam generator; however, the effects of air flow rate and mesh hole diameter were not studied, and there is a lack of mathematical models to predict expansion ratio and production rate. This work will design and build an improved foam generator, allowing the control of air flow rate and mesh hole diameter. The improved foam generator will be used to study the key properties of expansion foam for mitigating process safety incident, and the foam generation mechanism. In addition, predictive models of expansion ratio and production rate will be developed based on the experimental results. The findings of this study will provide a scientific basis for the design of foam generation system and the guideline of hazard mitigation operation for a process safety incident.