本文選題：煤自燃 + 高溫區(qū)域��； 參考：《重慶大學(xué)》2016年碩士論文

【摘要】：煤炭自燃是常見的煤礦災(zāi)害之一,在特定環(huán)境下,一旦某一區(qū)域的煤體氧化放出的熱量不能及時被漏風(fēng)產(chǎn)生的對流換熱和表面導(dǎo)熱作用帶走,溫度就會不斷升高導(dǎo)致火災(zāi),甚至引發(fā)爆炸。煤體自燃是由于煤體表面活性分子與氧氣接觸發(fā)生物理吸附、化學(xué)吸附和化學(xué)反應(yīng)三個階段,且放熱大于吸熱導(dǎo)致煤體溫度上升所引起的。煤體與氧氣接觸的過程中,將會伴隨著氣態(tài)產(chǎn)物的增加而氧含量減少的現(xiàn)象,并且同時會有吸熱與發(fā)熱效應(yīng)。熱量的產(chǎn)生導(dǎo)致煤與空隙內(nèi)氣體內(nèi)能改變及煤體內(nèi)部產(chǎn)生溫差,從而造成熱對流、熱傳導(dǎo)以及熱量的積聚。煤體內(nèi)部氣體成分、含量和內(nèi)能的變化將對氣體的運(yùn)移過程產(chǎn)生影響,而氣體運(yùn)移又與空氣滲流息息相關(guān),進(jìn)而引起氧氣含量的變化,又進(jìn)一步影響到熱傳導(dǎo)、熱對流、熱積聚、煤氧復(fù)合等一系列過程。影響煤自燃的因素有很多,不同地區(qū)煤體所處環(huán)境的不同導(dǎo)致引起煤自燃的因素有所差異。針對這一現(xiàn)狀,本文運(yùn)用絕熱氧化實(shí)驗(yàn)裝置、自然發(fā)火實(shí)驗(yàn)爐及熱分析儀等技術(shù),探討影響煤自燃過程的多種因素,為防滅火工作的開展提供一定的理論支撐。(1)供風(fēng)量對煤自燃全過程高溫區(qū)域時空變化規(guī)律影響的實(shí)驗(yàn)研究。利用絕熱氧化實(shí)驗(yàn)爐模擬煤自燃的全過程,深入分析不同階段煤體高溫區(qū)域的運(yùn)移機(jī)理,并且闡述指標(biāo)氣體的時空變化情況。(2)灰分對煤自燃影響的實(shí)驗(yàn)研究。采用絕熱氧化法探索不同含量灰分與煤自燃特性的相關(guān)關(guān)系,分析灰分的作用機(jī)理,并討論R70、CPT、B-M指標(biāo)受灰分影響的變化情況。(3)初始溫度對煤自然發(fā)火期的影響研究。本文運(yùn)用Boddington自然發(fā)火模型計(jì)算得自然發(fā)火期,將此模型所得值與實(shí)際測量值進(jìn)行驗(yàn)證,并且比較不同初始溫度下的自然發(fā)火期,建立了起始溫度與自然發(fā)火期關(guān)系模型,此模型為y=aexp(-x/b)+c。(4)煤自燃特性影響的熱重實(shí)驗(yàn)研究。運(yùn)用差熱熱重分析儀探索不同影響因素下煤樣各個特征溫度的變化規(guī)律,研究粒徑、升溫速率、煤質(zhì)對煤自燃反應(yīng)速率及放熱強(qiáng)度的影響。
[Abstract]:Spontaneous combustion of coal is one of the common coal mine disasters. In a specific environment, once the heat released by oxidation of coal body in a certain area cannot be taken away by convection heat transfer and surface heat conduction caused by air leakage in time, the temperature will keep rising and lead to fire. It even triggered an explosion. Spontaneous combustion of coal is caused by the three stages of physical adsorption, chemical adsorption and chemical reaction when the surface active molecules of coal are in contact with oxygen, and the exothermic is larger than the endothermic heat, which leads to the rise of coal temperature. In the process of contact between coal and oxygen, the increase of gaseous products will lead to the decrease of oxygen content, and there will be endothermic and heating effects at the same time. The heat production results in the change of gas energy in coal and air gap and the temperature difference in coal body, which results in heat convection, heat conduction and heat accumulation. The change of gas composition, content and internal energy in coal body will affect the gas migration process, and the gas migration is closely related to the air percolation, which causes the change of oxygen content, and further affects the heat conduction and thermal convection. A series of processes, such as thermal accumulation, coal and oxygen recombination, etc. There are many factors influencing coal spontaneous combustion. In view of this situation, this paper uses adiabatic oxidation experimental device, natural combustion furnace and thermal analyzer to discuss the factors that affect the process of coal spontaneous combustion. An experimental study on the effect of air supply on the space-time variation of coal spontaneous combustion in high temperature region is carried out in order to provide a theoretical support for the development of fire prevention and extinguishing. By using adiabatic oxidation furnace to simulate the whole process of coal spontaneous combustion, the migration mechanism of high temperature region of coal body in different stages is analyzed in depth, and the influence of ash content on coal spontaneous combustion is described. The relationship between ash content and spontaneous combustion characteristics of coal was investigated by adiabatic oxidation method, the mechanism of ash action was analyzed, and the effect of initial temperature on coal spontaneous combustion period was discussed. In this paper, the natural ignition period is calculated by using the Boddington spontaneous ignition model. The model is verified with the actual measured value, and the relation model between the starting temperature and the natural ignition period is established by comparing the natural ignition period at different initial temperatures. This model is a thermogravimetric experimental study on the effect of coal spontaneous combustion characteristics. By using differential thermogravimetric analyzer (DTA), the variation law of characteristic temperature of coal samples under different influence factors was explored, and the effects of particle size, heating rate and coal quality on coal spontaneous combustion reaction rate and exothermic intensity were studied.
【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：TD752.2

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 晉明月;董超;孫浩博;;煤自燃影響因素權(quán)重的灰色關(guān)聯(lián)度分析[J];煤礦安全;2012年12期

2 張立紅;;井下遺煤自燃的影響因素分析與研究[J];山西煤炭;2012年12期

3 譚波;胡瑞麗;高鵬;李凱;;煤自燃災(zāi)害氣體指標(biāo)的階段特征試驗(yàn)研究[J];中國安全科學(xué)學(xué)報(bào);2013年02期

4 賈淑潔;;煤自燃的原因及傾向性預(yù)測[J];科技傳播;2013年10期

5 高曉群;;煙煤自燃的分析與預(yù)防[J];中小企業(yè)管理與科技(下旬刊);2013年12期

6 郭興明,徐精彩,惠世恩;煤自燃過程中極限參數(shù)的研究[J];西安交通大學(xué)學(xué)報(bào);2001年07期

7 徐精彩,王華;煤自燃極限參數(shù)的神經(jīng)網(wǎng)絡(luò)預(yù)測方法[J];煤炭學(xué)報(bào);2002年04期

8 文虎,許滿貴,李莉,代愛萍;煤自燃的熱量積聚過程及影響因素分析[J];遼寧工程技術(shù)大學(xué)學(xué)報(bào);2003年02期

9 余明高,賈海林,潘榮錕;烏達(dá)礦區(qū)煤自燃預(yù)測標(biāo)志氣體研究[J];河南理工大學(xué)學(xué)報(bào)(自然科學(xué)版);2005年02期

10 劉愛華;蔡康旭;;青山礦煤自燃預(yù)報(bào)標(biāo)志氣體研究[J];煤炭科學(xué)技術(shù);2006年07期

相關(guān)會議論文 前9條

1 陸偉;;防治煤自燃新技術(shù)一高倍阻化泡沫[A];2007年全國煤礦安全學(xué)術(shù)年會會議資料匯編[C];2007年

2 豐丙章;;煤自燃火災(zāi)防治技術(shù)研究[A];2004全國阻燃學(xué)術(shù)年會論文集[C];2004年

3 肖e，

本文編號：1853477