Research On Test System For Self-heating Characteristics Of Typical Pyrogenic Materials

The spontaneous combustion of the pyrogenic materials is a common way in the fire.In recent years,many accidents have occurred because of the spontaneous combustion of pyrogenic materials.Typical pyrogenic materials,such as coal,ore sulfide,in its process of production,transportation,storage,spontaneous combustion occurs frequently,it threatens human life safety,pollutes the environment,and causes a lot of economic losses.In addition to the above materials,other pyrogenic materials,such as wood chips,tobacco,milk powder,flour,etc.,in the process of stack and transportation will befall spontaneous combustion.As the spontaneous combustion is concealed and dangerous,it is of great practical significance to study the self-heating process of the pyrogenic materials.Through the analysis and summary of the relevant literature at home and abroad,it is found that the spontaneous combustion of the pyrogenic materials is mainly related to the ambient temperature,humidity,water content,oxygen content,pore size and so on.The change of self-heating process temperature is the focus of recent research.Therefore,the test system in this paper is based on the temperature cross point method and is designed for temperature variables.The main contents of the thesis include three aspects: test method research,experimental system design and experimental test.The test method is Wire-Mesh Basket Crossing Point Method,and the temperature of the crossings of the samples at different initial temperatures is tested by measuring the temperature of the crossings of the materials in the specific experimental environment.The apparent activation energy and kinetic parameters were obtained by combining the kinetic equation and linear fitting.The test system consists of thermocouple,data acquisition equipment,constant temperature drying oven and the host computer software.The hardware part of the system mainly completes the temperature data collection during the experiment.The host computer software is based on the LabVIEW software platform.It is mainly responsible for the data collection and display,save and control the data acquisition device.The experimental test part mainly selected coal and sulfide ore as the experimental sample,through the laser particle size experiment to determine the experimental sample particle size range;Refer to the relevant literature to set the initial temperature of 100 ℃,120 ℃,130 ℃,140 ℃,test the temperature rise curve of the two materials,find the intersection temperature According to the slope and intercept of the linear equation,the apparent activation energy and the relevant kinetic parameters were obtained.Based on the spontaneous combustion mechanism of the pyrogenic materials,Wire-Mesh Basket Crossing Point Method and the multi-channel data acquisition system are combined to explore the temperature change of the self-heating process.In this paper,a small-scale simulation test system for the self-heating process of the pyrogenic materials is proposed.The experimental results are used to study the temperature change and correlation of the self-heating process of the pyrogenic materials by comparing the experimental results with the relevant research results.The determination of parameters is feasible and provides a new method and method for the study of self-heating process of pyrogenic materials.