商业厨房典型固体可燃物燃烧性能试验

Experimental study on the combustion characteristics of the solid fuel for the typical business kitchens

典型固体可燃物燃烧性能是研究商业厨房火灾发展的基础。利用锥形量热仪对商用厨房中油垢、大米和面粉3种典型固体可燃物的燃烧性能进行了研究,分析了可燃物的燃烧现象、点燃特性参数、热释放速率和烟气浓度、毒性等。结果表明,面粉容易点燃,采用封闭容器承装时,引燃时间会明显降低;油垢的热释放速率最高,在高热辐射功率时,峰值达到692.95 k W/m2,约为其他两种样品的5倍,面粉的火势增长指数随热辐射功率增高迅速增大;油垢的烟气浓度和CO、CO2产量最高,烟气产量高于其他两种样品100倍,CO、CO2产量是其他两种样品的1.4~11.65倍。

This article intends to report the results of our experiments with the solid fuels adopted by the typical business kitchens via a cone-shaped calorimeter. As is known, restaurant fires are character- ized with their beginning with or from the kitchen fire. Statistically speaking, kitchen fire tends to cost millions of loss of Yuan （RMB） and financial damage in the state or private revenue. What is more, thousands of people lust their lives, including the staff members of the restaurants and the diners over there. In this paper, we have adopted a cone-shaped calorimeter to study the combustion behaviors of the three kinds of typical solid fuels in the commercial kitchen, that is, fires caused by the cooked grease, rice and wheat flour. We have al- so analyzed the combustion behaviors of the fuel, the ignition parame- ters, the heat-releasing rate and the smoke density, as well as the toxicity the fires would bring about along with them. The results of our experiments show that, in the combustion process, it is likely for such accidents to come about as wheat flour and rice agglomeration, the intermediate muster and the carbonization. For example, the melting cooked grease tends to come about at first followed by the flash combustion. When the ignition time is analyzed, we have found that wheat flour is easy to get ignited, though the ignition time can be significantly reduced when it can be put out in the container. When the Janssens model is used to calculate the relation between the radia- tion intensity and the ignition time, it can be found that wheat flour and rice are the heat-thick substance prone to get fire for the fitted value of n is close to 0.5, though the cooked grease is not in the fit- ted value of n between 0.75 and 1. In addition, the peak thermos releasing rate for the aforementioned three samples tends to increase when the heat radiation intensity increases with the shortening of the combustion time. As a result of our study, the mean thermos release rate of the three samples has been detected between 50 - 80 kW/m2, with the peak value being between 88 - 145 kW/m2 in the sphere of the three thermos radiation capability. What is more, we have dis- covered the toxicity of the smoke, the cooked grease smoke toxicity and the specific extinction area can be made much higher than that of rice and flour. The result of our experimental study we have gained in the paper can thus be qualified to provide a series of important basic data for the design of a fire passive defense system for the commercial kitchen, as well as for fire prevention and fire extinction system.