The Destruction of High-Expansion Fire-Fighting Foam by the Components of Fuel Pyrolysis and Combustion.

摘要

Combustion and pyrolysis products in the air supply of high-expansion foam generators generally inhibit foam production. While this phenomenon is well documented,the mechanism is not known. The purpose of this research was to identify both the foam-breaking constituents and the mechanisms. Chemical constituents were identified both through literature search and measurements. Foam-breaking parameters were measured by the quality and quantity of foam generated when combustion products were introduced into a laboratory-scale foam generator,from the foamability of foam solution-containing products,by surface tension measurements with product-contaminated foam solutions,and by product gas diffusion through bubble walls. Half of the compounds tested detrimentally affect the production and/or stability of Hi-X foam. In an environment of high smoke concentration it is possible,at least on laboratory scale,to remove enough foam-breaking chemicals by water-spray scrubbing techniques so that foam formation will resume. (Author)