摘要
当发生液体火灾时,常使用泡沫快速扑灭.但传统泡沫存在较多缺陷,如泡沫所含成分全氟辛烷磺酰基化合物(PFOS)难以降解,长期积累会造成环境污染;热稳定性差,灭火后液体火灾易发生复燃.该文通过添加瓜尔豆胶制备了一种适用于液体火灾的环保型多糖聚合物泡沫,分析了该环保型多糖聚合物泡沫的发泡性能和稳定性能,明确了发泡剂、稳泡剂的浓度和配比,并与氟蛋白泡沫灭火性能进行了对比.结果表明:当脂肪醇聚氧乙烯醚葡糖苷(AEG)和椰油基糖苷(APG-0810)这2种环保型表面活性剂的质量比为2∶8且质量分数均为0.5％时,泡沫综合值最佳.随后分别添加质量分数为0.3％、0.4％和0.5％的瓜尔豆胶,发现质量分数为0.4％时,泡沫的灭火效果最好,灭火时间为82 s,比氟蛋白泡沫灭火时间缩短10s.使用该环保型多糖聚合物泡沫灭火后,25％复燃和90％复燃的对应时间分别为501和638s,比氟蛋白泡沫延长了 96.5％和114.1％,表明该环保型多糖聚合物泡沫具有良好的抗复燃性.该成果可为针对液体火灾的抗复燃泡沫配方研发提供参考.
Abstract
[Objective]Liquid fuel fires are commonly extinguished using foam;however,conventional foam formulations include perfluorooctane sulfonate,which does not degrade easily,causing environmental pollution and posing a threat to human health.Furthermore,traditional foams exhibit poor thermal stability and are prone to reignition after extinguishing.Thus,developing a foam that is both safe and environmentally friendly while exhibiting strong resistance to reignition is urgently needed.However,most of the current research is limited to laboratory parameter measurements and mainly focuses on the development of new foams for solid fires,such as coal fires,which have considerable differences in fire suppression mechanisms and foam performance requirements from liquid fires.At present,research on highly stable and environmentally friendly foam formulations specifically designed for liquid fires is limited.This study aims to replace hazardous fluorocarbon surfactants with safe and biodegradable hydrocarbon surfactants and incorporate natural hydrophilic polymer guar gum to develop an environmentally friendly polysaccharide foam suitable for liquid fires.Analysis of the foaming and stability performance of the developed foam is conducted,and the concentrations and ratios of foaming agents and stabilizers are determined.Finally,the fire suppression performance of the developed foam is compared with that of the fluoroprotein foam(FFFP).[Methods]The foam expansion ratio and half-life were estimated,and the comprehensive values were computed to determine the optimal laboratory foam formulation with high comprehensive parameters.However,the direct estimation of the fire suppression time of the foam during liquid fire extinguishment was difficult as it was influenced by various factors such as foaming performance,stability,and flowability.Thus,a 0.8 m-diameter scaled-down oil pan was constructed,and the laboratory foam formulation with higher comprehensive parameters was further tested for its fire suppression performance and compared with the commercial FFFP.After complete extinguishment,a 5-minute cooling period was implemented,followed by an evaluation of the foam's resistance to reignition using a burn-back tank.[Results]The findings revealed that:(1)The foam presented the highest comprehensive value of 133.4 at an mass ratio of AEG and APG-0810 of 2∶8,with a mass fraction of 0.5％.The foam expansion ratio was 14.5,and the half-life was 10.8 min.(2)When the concentration of guar gum was 0.4％,the comprehensive value of the foam stabilized and exhibited the best fire suppression performance.The 90％control time was approximately 52 s,and the extinguishment time was 82 s.Comparing the control and extinguishment times of the developed foam with those of FFFP,the new formulation showed reductions of 16.1％and 10.9％,respectively.(3)At a guar gum concentration of 0.4％,the developed foam exhibited the best resistance to reignition.The 25％,90％,and complete reignition times compared to FFFP were extended by 96.5％,114.1％and 113.7％,respectively.[Conclusions]By replacing hazardous fluorocarbon surfactants with biodegradable hydrocarbon surfactants(APG-0810 and AEG)and introducing the natural hydrophilic polymer guar gum,the developed foam has improved viscous and water-retention properties,leading to a substantially improvement in its resistance to reignition.This study offers a reference for developing new reignition-resistant foam formulations specifically designed for liquid fires.
基金项目
重点研发计划(十四五)(2022YFC3004902)
应急管理部消防救援局重点研发项目(2022XFZD04)
中央高校基本科研业务费专项(2023JCCXAQ05)
维普
万方数据