Study on the relationship between the particle size distribution and the effectiveness of the K‐powder fire extinguishing agent

Abstract

Summary The relationship between the particle size distribution and the extinguishing effectiveness of the new K‐powder fire extinguishing agent has been studied experimentally, to explore the reason of the great extinguishing efficiency exhibited by the new K‐powder fire extinguishing agent on Class B fire (liquid fuel fire). The results of the experiment showed that the extinguishing effectiveness increased along with the decrease of the particle size distribution. In addition, a sharp discontinuity appeared around the limiting size, about 40 μm. The powder with the particle size below 40 μm exhibited highly effective extinguishing with the minimum effective extinguishing concentration Cxr = 23 g·m−3, while the powder with the particle size above 40 μm exhibited little fire extinguishing efficiency. Compared with other fire extinguishing agents produced by different substances, the new K‐powder fire extinguishing has the bigger limiting size. That means, in the same particle size distribution, the new K‐powder fire extinguishing agent contains more highly effective powder than others contain, and is more effective.

Fire‐suppression efficiency and extinguishing mechanisms of calcium acetate using heptane cup‐burner flames

“…The flame‐inhibition ability of Ca(OAc) 2 was the highest flame‐inhibition ability among the tested calcium compounds, as summarized in Table 2; however, the CaO powder generated from Ca(OAc) 2 had the largest D 32 value among the samples, as listed in Table 3. Several researchers 33–36 have discovered a negative relation between particle size and fire‐suppression ability; the fact contradicts the findings of particle size analyses. Consequently, we rejected hypothesis (i) and we concluded that Ca(OAc) 2 's extinguishing ability is most likely governed by a factor (ii): its high ability to generate inert gases.…”

Optimization Simulation of Ultrafine Dry Powder Blow-Assisted Pipe Based on CFD

“…However, halon extinguishing agent is harmful to the environment and has been banned for a long time [2][3][4]. In recent years, many scholars have studied a large number of extinguishing agents [5][6][7][8][9][10][11] that can replace halon. After comprehensively considering the spraying cost and extinguishing effect, ultrafine dry powder is considered as the extinguishing agent for the WTFT.…”

Insights into the particle diameter and base chosen for dry powder fire extinguishing agents

“…The search for alternatives promoted the examination of the effectiveness of several gasses, liquids, and dry powder agents 3–6 . It was shown that the dry powder agents that contain the elements Na and K were the most effective in extinguishing fires, especially NaHCO 3 (SB) and KHCO3 (PB), which have been widely used and proved to be several times more effective than Halon 1301 7–9 …”

“…[3][4][5][6] It was shown that the dry powder agents that contain the elements Na and K were the most effective in extinguishing fires, especially NaHCO 3 (SB) and KHCO3 (PB), which have been widely used and proved to be several times more effective than Halon 1301. [7][8][9] In designing dry powder agents, particle diameter and base were important factors. First, there is a significant correlation between particle diameter and the flame-inhibiting effectiveness of dry powder agents.…”

“…10 Laffitte et al 11 studied the influence of particle diameter on the extinction of flames and found that flame was best inhibited by a substance of optimum particle diameter. Yan et al 8 studied the relationship between the particle size distribution and the effectiveness of the K-powder fire extinguishing agent. The particle diameter was closely related to the thermodynamic properties of dry powder agents.…”