Study On Bubble Purification Mechanism Of Flame Retardant Cable Fire Smoke

The initial stage of the fire is the best time for the trapped people to evacuate and rescue.However,the high-temperature toxic and harmful smoke leads to the reduction of visibility at the fire site and hinders the escape and rescue of personnel.Therefore,smoke purification is the key to the escape and rescue of personnel at the initial stage of the fire.Therefore,a new technology of fire smoke purification based on bubble is proposed in this paper.Through the research and development of bubble purifying agent suitable for specific fire smoke,the huge amount of free bubbles generated by the self-developed foaming device are used to wet and adsorb the smoke,neutralize the acid gas therein,so as to achieve the purpose of quickly purifying the smoke and increasing the escape and rescue opportunities.According to statistics,about 80%of fires are electrical fires.In this paper,the smoke from cable fire is taken as the research object,and the bubble purifying agent suitable for flame retardant cable fire smoke is developed,and its theoretical and experimental research is carried out.The main results are as follows:（1）Through the study of pyrolysis kinetics and reaction mechanism of flame retardant cable,it is found that the heat resistance of PVC material in flame retardant cable is weaker than that of cross-linked polyethylene（PE）material;In the pyrolysis reaction of PVC materials,hydrogen chloride（HCl）gas,water（H₂O）and carbon dioxide（CO₂）are mainly produced;The pyrolysis reaction of crosslinked PE materials is mainly the production of alkane groups.（2）Through the study on the performance of surfactants,it is concluded that the fm-20ab:alsa mixed solution with a concentration of 0.7%is used as the foaming agent of bubble purifier,in which the ratio of FM-20AB to ALSA is FM-20AB:ALSA=2:1.（3）By adding different foam stabilizers and neutralizers to the foaming agent of the bubble purifier,the types and concentrations of the additives of the bubble purifier are determined.Finally,the ratio of the bubble purifier is（FM-20AB:ALSA=2:1）:pva:low viscosity sodium carboxymethyl cellulose:Na₂SO₃=0.7%:0.08%:0.05%:0.15%.（4）Under the wetting action of bubble cleaner,the hydrogen bonds on the surface of carbon black increased,the van der Waals force between carbon black particles increased,and the hydrophilicity increased;The HCl gas produced in the flue gas is neutralized by adding weak alkaline sodium sulfite（Na₂SO₃）,so as to achieve the purpose of flue gas purification.In conclusion,the bubble purifier can effectively deal with the smoke hazards caused by the burning of flame-retardant cables at the initial stage of the fire,and extend the evacuation time and rescue opportunities of people at the initial stage of the fire.The research results of this paper will provide theoretical and technical support for fire rescue and escape.