Accession Number:

ADA456229

Title:

Improving Water Spray Efficacy for Fire Suppression via CO2 Addition at High Pressures and Low Temperatures: Evidence for CO2 Clathrate Hydrate Formation

Descriptive Note:

Journal Article

Corporate Author:

APPLIED RESEARCH ASSOCIATES INC TYNDALL AFB FL

Report Date:

2006-01-01

Pagination or Media Count:

13.0

Abstract:

This paper describes a technique for achieving a compact aqueous spray that incorporates CO2 into the spray at low temperatures T 10C and high pressures P 10 MPa. A high-pressure spray apparatus was used to explore the effects of temperature 4-25 C, nominal CO2 mole fraction 0-0.12, in-line filter pore size 0.5-7 micrometer, and additives on the high-pressure 12-19 MPa water spray patterns. Divergence of the high-pressure H2O-CO2 spray was significantly reduced at low temperatures, with addition of sodium lauryl sulfate or aqueous film-forming foam AFFF, and with a small-pore-size 0.5 micrometer filter. The observed trends, based on digital images, can be explained by the formation of CO2 clathrate hydrate within the continuous-flow system. The concepts discussed herein may be applied to conventional H2OAFFF fire-suppression systems, where the introduction of CO2 as a foaming agent can increase fire-suppression efficacy.

Subject Categories:

  • Inorganic Chemistry
  • Organic Chemistry
  • Safety Engineering
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE