Study on the effectiveness of compressed air foam to inhibit water-soluble liquid fire
Study on the Effectiveness of China's Safe Production Science and Technology Compressed Air Bubbles to Suppress Water-Soluble Liquid Fires Bao Zhiming 12, Chen Tao, Fu Xuecheng, Zhang Yizhong, Wang Rongji 1 a Tianjin Fire Research Institute, Ministry of Public Security, Tianjin 300381, China; 2. Fire Fighting and Rescue Technology Ministry of Public Security. Table 1 Compressed air bubble extinguishes the fire extinguishing performance level of the liquid fire. Fire extinguishing performance level Anti-burning level Fire extinguishing time Anti-burning time 矣 3 15矣3 10矣5 15矣5 10 2 Test results and discussion 6% anti-resistant is used in this test The water-soluble film-forming foam fire extinguishing agent and 6% synthetic anti-solvent foam fire extinguishing agent were used as test samples, and the fire extinguishing test results are shown in Table 2. The test results show that: (1) The anti-solvent foam extinguishing agent is used in the compressed air foam fire extinguishing system, and the sound is capable of fighting water-soluble liquid fire. The fire-fighting performance is measured and evaluated, generally through the use of fire extinguishing agent, fire control time, fire-extinguishing time, anti-burning time and other indicators, of which fire-fighting time and anti-burning time are the two most important indicators. The data in Table 2 shows that AFFF/AR and S/AR have a certain ability to extinguish water-soluble liquid fires when considering the fire-extinguishing time and 25% anti-burning time; (2) The suitable foam state plays an important role in foam fire-extinguishing effect. important. Whether it is AFFF/AR or S/AR, the fire extinguishing time is shorter and the anti-burning time is longer under the condition of higher expansion ratio, and then the foam fire extinguishing performance level is improved from ARIB to ARIA. Table 2 anti-foaming agent Dehydration water-soluble liquid fire test result sample number: 曰 比 ratio /% foaming multiple liquid time extinguishing time burning time fire extinguishing performance level The traditional low-fold foam generating system is generally an aspirating foam generating system, when the foam solution is under a certain pressure When passing through a foam nozzle or orifice plate. Due to the sharp reduction of the flow cross section. The pressure position of the liquid stream can be rapidly converted into kinetic energy to make the foam solution a high-speed jet. The fluid micelles in the jet move irregularly, collide with the surrounding air, collide, blend, and transmit momentum to the air layer in contact with the jet boundary, and continuously entrain this part of the air into the mixed diffusion tube to form gas- Liquid mixed stream. As the air is continuously taken away, a certain negative pressure is formed in the suction hole area, and external air continuously enters the air chamber under the action of atmospheric pressure, so that a certain number of foams are continuously generated 08. The compressed air foam generating system can adopt air compression. Machine or compressed gas cylinders fill the foam solution with an appropriate amount of compressed air into the foam solution, and according to the amount of different foaming foams, which are different foaming ratios, which is important for the production of compressed air foam and the way of aspirating foam. The difference lies in the way the foam is produced. 09 Different foam generation methods often have different fire extinguishing effects. In order to have a more intuitive understanding of the fire-retardant performance of the anti-solvent fire extinguishing agent in the way of compressed air foam generation, we conducted a comparative test on the fire-extinguishing performance of the compressed air foam generation method and the aspirating foam production mode. The test results are as follows. Table 3 shows. The test results show that when the compressed air foam is adjusted to a suitable expansion ratio, the fire-extinguishing performance of the compressed air foam is superior to that of the aspirating foam. The main reason is that the compressed air foam can be produced by the foam solution. The method of actively charging the air allows the foaming ratio of the foam to be adjusted as needed within a certain range, and generally can obtain a foaming multiple higher than that in the manner of generating the aspirating foam. Higher foaming ratios generally provide better foam stability M and, in turn, increase the fire resistance time of the fire fighting foam. It can be seen from Table 3 that the 25% liquid separation time of the compressed air foam is generally longer than that of the aspirating foam, and the 25% anti-burning time also follows this rule. The main reason for the improvement of foam stability is that the compressed air foam generation method improves the microstructure of the fire-fighting foam and obtains a fire-fighting foam with a more uniform particle size distribution, and the bubble particle size uniformity of the fire-fighting foam is important for its stability. Factor 111. Table 3 Comparison of fire-fighting performance of compressed air bubble generation mode and aspirating bubble generation mode Sample foam production foaming fire extinguishing property number mode multiple liquid time time burning time energy level compressed air foam system aspirating foam generation system The compressed air foam system aspirating foam generation system must point out that due to the high cost of the standard oil pan fire test and the high requirements for the test environment, this study is currently only for the effectiveness of compressed air foam to inhibit water-soluble liquid fire. Initial verification was carried out. If you want to further clarify the optimal use conditions of each foam fire extinguishing agent on the basis of suitable foam state, it should be optimized and verified according to the characteristics of the product and further standard fire and fire fighting, and further research through relevant basic research. The rheological properties of the compressed air foam structure and liquid separation stability are clearly defined. Nevertheless, the results of this experiment still have a strong theoretical and practical significance. The importance of this is to prove the effectiveness of compressed air foam to suppress aqueous liquid fire on the one hand, and provide an effective guidance for expanding the scope of combat of compressed air foam fire trucks that have become the main firefighting force of some local firefighting forces. At the same time, the compressed air foam fire truck with dubbing A foam fire extinguishing agent and anti-foam foam extinguishing agent can simultaneously adapt to solid fire, water-insoluble and water-soluble liquid fire, and improve the application range of advanced sounding. On the other hand, it provides important technical support for the application of compressed air foam fire extinguishing technology in fixed foam fire extinguishing systems, and provides an important role for fixed foam fire extinguishing systems in fire protection applications of water soluble liquid storage tanks. 3 Conclusions Anti-solvent fire extinguishing agents have the property of inhibiting aqueous liquid fires when used in compressed air foam systems. The suitable foam state is extremely important for the foam fire-extinguishing effect. When the foaming multiple is more than 20 times, the fire-extinguishing performance indexes such as fire-extinguishing time and anti-burning time are improved. The improvement in foam stability is an important reason for the excellent fire-extinguishing properties of compressed air foam generation. At the same time, dubbing A foam fire extinguishing agent and anti-foam foam extinguishing agent can make compressed air foam fire trucks adapt to various fire types such as solid fire, water-insoluble and water-soluble liquid fire. Coating Machinery,Bottom Spray Coater,Pharmaceutical Coating Machine,Tablet Film Coating Machine Changzhou Bole Tech Co.,Ltd , https://www.boledrying.com