超细粉体三相泡沫灭火剂热稳定性研究

Study on thermostability of three-phase foam extinguishing agent incorporating ultra-fine powder

为探讨超细粉体的加入对水基泡沫灭火剂油面热稳定性的影响,用自行设计的小尺寸可视化油池,完成不同粉体类型、不同添加量的泡沫油面热稳定性试验。观察高温条件下三相泡沫的形态变化过程,并用热电偶测定试验过程中的油品温度,优选2种适合制备防灭火三相泡沫的超细粉体。结果表明:向泡沫灭火剂中加入超细粉体,可使其在高温下的稳定时间延长10倍以上;对于空心玻璃微珠和炭粉,泡沫灭火剂的油面热稳定性随粉体添加量的增加而增强,发泡倍数随粉体添加量增加而减小,炭粉对发泡性能的影响更为显著,空心玻璃微珠和炭粉的最优添加量(质量分数)分别为11.2%和13.2%;高温条件下,粉体在泡沫表层形成致密外壳,阻碍油品与环境的传热传质过程,防止油品复燃。

To study thermostability of aqueous foam extinguishing agent incorporating ultra-fine powders,experiments were carried out in a self-designed small scale oil pool. Shape changing process of the threephase foam at high temperature was analyzed. Two kinds of ultrafine powders suitable for preparation of the fire-extinguishing three-phase foam were selected. The results show that the foam stabilization time at high temperature can be extended more than 10 times with the ultra-fine powders incorporated,that thermostability of foam on oil surfaces increase with an increase in the additive amount of hollow glass microsphere and graphite powder,but the foaming performance has opposite regularity,the addition of graphite powder has a more obvious effect on the foaming process,that the optimum adding amounts of hollow glass microsphere and graphite powder are 11. 2wt. % and 13. 2wt. % respectively,and that the ultra-fine powders can create a denser and uniform protective layer spreading on the top of the oil to block the heat and mass transfer processes between the oil and environment.