| The spontaneous combustion phenomenon of coal occurred more frequently with the increase of underground mining depth and the environmental temperature of coal,which causing a growing number of secondary disasters and serious restricted the development of deep mining of coal mine in our country.Sun-cun is located in the eastern of the Xinwen coal mine in Shandong province, the mining depth has already reached-1300 m, downhole temperature is more than 40 ℃ in local area.Serious disasters has caused by the frequent phenomenon of coal spontaneous combustion that has affected the safety of normal production of Sun-cun coal mine, therefore, the study on the characteristics of coal low temperature oxidation process in high temperature environment like Sun-cun is an urgent need, and thus offers Corresponding help to further prevention and control work in Sun-cun coal mine.Firstly, because in the process of spontaneous combustion of coal oxidation reflect the nonlinear characteristics of the significant, the cusp mutation theory is introduced in this paper systematic analysis model of the mine coal spontaneous combustion process,and combined with the measured data of the Sun-cun coal mine, based on the two types of hazard theory selection in the process of coal spontaneous combustion of internal and external factors as variables in the model to calculate, finally it is concluded that the mine mutation model expression.The formation of coal spontaneous combustion is the result of many factors, According to the theory of the two kinds of risk sources, many factors are summarized as the intrinsic influence factor set U and the external influence factor set V, and gives the quantitative description of the method in the U and V realizes the quantification processing, then to mine coal spontaneous combustion process of formation and development of mutation analysis. according to the mathematic expression of the model to draw its mutation popular figure to explain the change of the system function characteristics and ore Sun-cun hysteresis characteristics of coal spontaneous combustion,and taking the multiple coal seam of the mine as sample, the mathematical expression of the catastrophe model and its catastrophe manifold diagram are used to verify the analysis of the spontaneous combustion.The calculation results of the test sample show that the model can better reflect the whole process of coal oxidation and spontaneous combustion.From the above analysis, it can be concluded that the more likely to be spontaneous combustion, the more likely it is to be in the right boundary.In the actual production process of the Sun-cun coal mine, the process shouldbe paid enough attention to in order to ensure the safe production of coal mine.The occurrence and development of coal mine spontaneous combustion is a nonlinear process.Using the theory of cusp catastrophe theory, the nonlinear bifurcation theory is able to analyze the complex, dynamic and nonlinear phenomena of mine natural fire.In the safety management of coal mine, the lag of the coal spontaneous combustion catastrophe model should be paid enough attention.Once the occurrence of coal spontaneous combustion accidents, the disturbance energy must make the input energy greater than the spontaneous formation, to extinguish the fire.That is to say, the consequences of coal spontaneous combustion is quite painful, to extinguish the fire, the cost will be greater.Secondly,combined with the existing coal self-ignition orientation evaluation method analysis of the advantages and disadvantages,This paper uses fuzzy extension found theory is suitable for the mine the truth Coal spontaneous combustion propensity to judge model is established.In view of the traditional laboratory evaluation method,and previous development of all kinds of comprehensive evaluation model of deficiency,Introduced the concept of fuzzy membership degree theory.The unit of different linear dimensionless parameters,and a handle,This paper proposes a fuzzy hierarchy analysis was then used a simple correlation functions,finally using the theory of extension evaluation,according to the actual situation of Sun-cun coal mine.There can be a destination measured the various factors affecting the required parameters,considering to get better results.Calculated with the actual situation of exactly the same results, confirmed on the basis of extension theory based on fuzzy basic can achieve accurate judging criteria of coal self-ignition orientation.In accordance with the established evaluation model and level of coal self-ignition orientation variable characteristic value can be obtained.In the same way, calculated 13#coal seam 72036 working face illustrate the self-ignition orientation level and 15# coal seam working face in more than 91053 mining face to the second level,that is to say self-ignition orientation is relatively small.According to this,Sun-cun coal mine in prevention and treatment of spontaneous combustion of coal mine and a degree of execution of 15# coal seam in 91053 working face is more priority than 13# coal seam in72036 working face.The self-ignition orientation level evaluation includes represents the level of coal self-ignition orientation bias degree of variable characteristic value.The party can be based on this data is simple and efficient and reasonable arrangements for the work to the prevention and control work priority,and can be more targeted toformulate the corresponding prevention management plan.In addition, The according to the measured data of the mining area established relationship model of Sun-cun coal mine this kind of ultra kilometer mine downhole temperature and mining depth, analysis of Sun-cun mine spontaneous combustion period is calculated the core problem is to under the condition of high temperature coal exothermic oxidation of coal oxygen in the process of reaction exothermic in three ways,namely, physical adsorption, chemical adsorption, the chemical reaction of coal and oxygen difference. With this feature, the results of the optimization of the existing models of spontaneous combustion are more in line with the actual spontaneous combustion period in Sun-cun. Based on this, the essence of the exothermic reaction in the first two stages of the coal combustion process is analyzed, and the important value of the differentiation of the three ways of the exothermic reaction of coal is determined,and then the model is optimized by this point of view, and the model is applied to predict the spontaneous combustion period of 15# coal seam of Sun-cun coal mine.The results show that the accuracy of the original model is improved,and this data as the basis,select the most prominent characteristics of the village coal mine, namely the depth of the mine and coal spontaneous combustion process is widely recognized by the concentration of carbon monoxide as a characterization parameter,the mathematical expression of the relationship between the two party and the value of the model is expressed in the form of power function, and it can provide a practical reference value for the actual coal spontaneous combustion prevention and control.Finally,In order to improve the control method of coal spontaneous combustion,this paper first proposed the use of microbial technology to control oxygen concentration and achieve the effect of controlling coal spontaneous combustion. first,the characteristics of coal samples were analyzed by microscopic study. The advantages of Fe and C were analyzed qualitatively by using scanning electron microscope. Process is generated from the micro pores on the surface of the coal and these pores due to the ability to store oxygen and reflect with coal exothermic oxidation caused by temperature rise and gradually become big characteristics. Based on the theoretical premise, the spirit of the idea of the oxygen concentration in the control of coal seam, select Bacillus subtilis culture preparation and laboratory co MParison test and site engineering practice in the prevention and treatment, has been mixed in different culture medium and beef extract peptone liquid, under the condition of room temperature Bacillus subtilis lead to CO2 and O2 evolving rules, experiments show that under the conditions, due to the CO2 produced by Bacillus subtilis leads to oxygen concentration Greatly reduced. With Bacillus subtilis in flour, flour and liquid culture combine to form a viscous liquid can effectively closed pulverized coal leakage effect due to, in the closed and can produce large amounts of CO2, so as to achieve the best effect of prevention of coal spontaneous combustion and the effect through further practice strongly proved. Conclusions are drawn as follows: the microbial flora of CO2 can be effective prevention and control of coal spontaneous combustion, the Bacillus subtilis and different culture base generated CO2 rules and application in engineering has extensive engineering application prospects. |
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