【摘要】：中低階煤在我國煤炭儲(chǔ)量中占一半以上,具有揮發(fā)分含量高、水含量高和發(fā)熱量低等特點(diǎn)。通過熱解轉(zhuǎn)化可得到提質(zhì)半焦,熱解氣和煤焦油(高附加值化學(xué)品),實(shí)現(xiàn)低階煤分級煉制與清潔轉(zhuǎn)化。為提高熱解焦油收率、改善焦油品質(zhì),方法有:一是要強(qiáng)化煤熱解初期的分解程度,盡可能多的產(chǎn)生小分子,充分利用煤顆粒自身和環(huán)境中的氫及小分子自由基片段;二是要對熱解初次產(chǎn)物(焦油前驅(qū)體)的二次反應(yīng)進(jìn)行調(diào)控,實(shí)現(xiàn)溫和條件下焦油中某一類組分的富集轉(zhuǎn)化。當(dāng)前,采用半焦熱載體的煤熱解提質(zhì)技術(shù),可回收產(chǎn)物半焦部分顯熱,提高系統(tǒng)熱效率;熱解過程釋放的揮發(fā)分可經(jīng)半焦裂解,焦油輕質(zhì)組分含量增加。本文在課題組前期研究基礎(chǔ)上,主要采用固定床反應(yīng)器考察陶瓷球、橄欖石、石英砂、半焦熱載體對呼倫貝爾褐煤和神東長焰煤熱解的影響。結(jié)合焦油輕質(zhì)組分測定結(jié)果,分析揮發(fā)分在不同熱載體作用下的裂解轉(zhuǎn)化;在神東煤熱解中引入神東煤直接液化殘?jiān)?研究兩者共熱解相互作用;考察共熱解焦為固體熱載體類工業(yè)條件的循環(huán)穩(wěn)定性,分析產(chǎn)物組成及半焦粒度變化;對于半焦熱載體神東煤熱解的作用機(jī)制,結(jié)合焦油組成及反應(yīng)前后熱載體半焦物化性質(zhì)改變,分析溫度對半焦熱載體裂解揮發(fā)分的影響。主要結(jié)果如下:1.不同熱載體褐煤熱解實(shí)驗(yàn)表明,陶瓷球作用下褐煤揮發(fā)分深度裂解,伴隨熱解水生成。以褐煤半焦為固體熱載體時(shí),揮發(fā)分與半焦作用,焦油輕質(zhì)組分增加,熱解氣中H2和CO2不同程度的提高。熱重分析表明,褐煤半焦熱載體表面沉積的碳物種可促進(jìn)其在更高溫度下的熱解。2.驗(yàn)證了焦油回收過程-先用四氫呋喃洗滌,旋蒸除去溶劑和熱解水,再用正己烷萃取得到輕質(zhì)組分方法的可靠性。對不同熱載體作用下神東煤焦油輕質(zhì)組分進(jìn)行GC-MS測定,依據(jù)物質(zhì)定性結(jié)果劃分為四類組分;結(jié)合相對含量變化結(jié)果,認(rèn)為焦油中的酚類會(huì)向芳烴結(jié)構(gòu)轉(zhuǎn)化。3.考察了共熱解焦固體熱載體的神東煤與液化殘?jiān)矡峤庀嗷プ饔?與石英砂熱載體相比,共熱解焦對揮發(fā)分有裂解作用;與共熱解理論計(jì)算值相比,共熱解過程中產(chǎn)生正協(xié)同作用(ΔY0)。共熱解焦固體熱載體的10次循環(huán)共熱解實(shí)驗(yàn)表明,經(jīng)過一定次數(shù)循環(huán)后,半焦黏結(jié)團(tuán)聚與新生成半焦補(bǔ)充存在的抵消作用,共熱解焦熱固體載體粒徑分布趨于穩(wěn)定。4.改變半焦熱載體初始溫度得到神東煤熱解焦油收率變化,是由熱載體與反應(yīng)物料的溫差引起的瞬時(shí)加熱速率差異,煤的熱解深度、焦油前驅(qū)體物種的裂解、揮發(fā)分與熱載體半焦作用等因素綜合影響的結(jié)果。5.煤熱解揮發(fā)分受到熱載體半焦催化裂解和高溫?zé)崃呀夤餐饔?前者在較低溫度范圍內(nèi)明顯,后者在高溫范圍內(nèi)明顯。高溫不利于焦油中酚類的穩(wěn)定存在,導(dǎo)致酚羥基分解或縮聚,焦油中多環(huán)芳烴結(jié)構(gòu)含量增加。揮發(fā)分與半焦熱載體作用對半焦碳結(jié)構(gòu)影響不大;揮發(fā)分的部分縮聚產(chǎn)物在半焦表面沉積引起其表面一些官能團(tuán)結(jié)構(gòu)變化,影響半焦的后續(xù)利用。6.隨著半焦熱載體初始溫度增加,在熱載體表面的形成的碳物種不僅有量的區(qū)別,還有結(jié)構(gòu)上的差異。熱解過程中在熱載體半焦表面發(fā)生焦油附著、裂解和縮聚積碳產(chǎn)物的沉積,對半焦CO2氣化反應(yīng)性促進(jìn)作用大于比表面下降的不利影響。
[Abstract]:Medium and low rank coal accounts for more than half of China's coal reserves, and has the characteristics of high volatile content, high water content and low calorific value. One is to enhance the decomposition degree of coal at the initial stage of pyrolysis, to produce as many small molecules as possible, and to make full use of hydrogen and small free radical fragments in coal particles and the environment; the other is to control the secondary reaction of the primary product (tar precursor) of pyrolysis, so as to realize the enrichment and transformation of a certain kind of components in tar under mild conditions. The coal pyrolysis technology with semi-coke heat carrier can recover the sensible heat of semi-coke and improve the thermal efficiency of the system; the volatile matter released during pyrolysis can be pyrolyzed by semi-coke, and the content of light components in tar increases. The pyrolysis of Hulunbeier lignite and Shendong long flame coal was studied. The pyrolysis conversion of volatile under different heat carriers was analyzed by combining the results of determination of light components of tar. The main results are as follows: 1. The pyrolysis experiments of lignite with different heat carriers show that ceramic balls are used as ceramic balls. When lignite semi-coke is used as solid heat carrier, the light components of tar increase, and H2 and CO2 in pyrolysis gas increase in varying degrees. Thermogravimetric analysis shows that carbon species deposited on the surface of lignite semi-coke heat carrier can promote its pyrolysis at higher temperatures. The recovery process of tar was studied. The light components of Shendong coal tar were determined by GC-MS under the action of different heat carriers. According to the qualitative results, the tar was divided into four types. The co-pyrolysis interaction between Shendong coal and liquefied residue was investigated. Compared with the quartz sand heat carrier, the co-pyrolysis coke had a pyrolysis effect on volatile matter. Compared with the theoretical value of co-pyrolysis, the co-pyrolysis process had a positive synergistic effect (Y0). The results of 10 cycles of co-pyrolysis show that the particle size distribution of thermal solid carrier tends to be stable after a certain number of cycles. 4. The change of tar yield of Shendong coal pyrolysis is induced by the temperature difference between thermal carrier and reaction material. The results show that the instantaneous heating rate is different, the pyrolysis depth of coal, the pyrolysis of tar precursor species, and the effect of volatile and heat carrier char on the pyrolysis of coal. 5. High temperature is not conducive to the stable existence of phenols in tar, resulting in the decomposition or condensation of phenolic hydroxyl groups, and the increase of polycyclic aromatic hydrocarbons in tar. 6. As the initial temperature of the semi-coke heat carrier increases, the carbon species formed on the surface of the semi-coke are not only different in quantity, but also in structure. Ringing.
【學(xué)位授予單位】：太原理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TQ530.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 周琦;;低階煤提質(zhì)技術(shù)現(xiàn)狀及完善途徑[J];潔凈煤技術(shù);2016年02期

2 許修強(qiáng);王永剛;陳宗定;白磊;張錕俊;楊薩莎;張書;;勝利褐煤半焦冷卻處理對其微觀結(jié)構(gòu)及反應(yīng)性能的影響[J];燃料化學(xué)學(xué)報(bào);2015年01期

3 王向輝;門卓武;許明;翁力;劉科;;低階煤粉煤熱解提質(zhì)技術(shù)研究現(xiàn)狀及發(fā)展建議[J];潔凈煤技術(shù);2014年06期

4 余振鵬;張丹;郭瑞麗;張建樹;;熱解氣催化活化促進(jìn)石河子煙煤熱解的研究[J];煤炭轉(zhuǎn)化;2014年04期

5 高松平;王建飛;趙建濤;王志青;房倚天;黃戒介;;CO氣氛下褐煤加壓快速熱解過程中CH_4的逸出規(guī)律[J];燃料化學(xué)學(xué)報(bào);2014年06期

6 杜鵬鵬;孫鳴;陳靜;陳繁榮;馬曉迅;;陜北中低溫煤焦油常壓重油餾分GC-MS分析[J];化學(xué)工程;2014年03期

7 王汝成;王寧波;王明峰;霍鵬舉;王永娟;孫鳴;馬曉迅;;中低溫煤焦油中酚類化合物的柱層析分離[J];煤化工;2013年06期

8 喬星星;王永;王影;張永發(fā);;低階煤氣體載熱低溫干餾工藝研究進(jìn)展[J];能源與節(jié)能;2013年12期

9 陳琳;孟雪松;吳洪新;凌鳳香;;一種低溫煤焦油的高分辨核磁共振研究[J];精細(xì)石油化工;2013年06期

10 林雄超;王彩紅;田斌;張書;周劍林;王永剛;;脫灰對兩種煙煤半焦碳結(jié)構(gòu)及CO_2氣化反應(yīng)性的影響[J];中國礦業(yè)大學(xué)學(xué)報(bào);2013年06期

相關(guān)博士學(xué)位論文 前5條

1 趙鋼煒;褐煤熱解定向轉(zhuǎn)化的實(shí)驗(yàn)研究[D];中國科學(xué)院研究生院（工程熱物理研究所）;2014年

2 周劍林;低階煤含氧官能團(tuán)的賦存狀態(tài)及其脫除研究[D];中國礦業(yè)大學(xué)（北京）;2014年

3 王娜;提質(zhì)低階煤熱解特性及機(jī)理研究[D];中國礦業(yè)大學(xué)（北京）;2010年

4 吳詩勇;不同煤焦的理化性質(zhì)及高溫氣化反應(yīng)特性研究[D];華東理工大學(xué);2007年

5 劉生玉;中國典型動(dòng)力煤及含氧模型化合物熱解過程的化學(xué)基礎(chǔ)研究[D];太原理工大學(xué);2004年

相關(guān)碩士學(xué)位論文 前3條

1 馬江山;固體熱載體法神東煤熱解以及與液化殘?jiān)矡峤庋芯縖D];太原理工大學(xué);2015年

2 孔嬌;煤熱解過程中酚類化合物的生成規(guī)律[D];太原理工大學(xué);2013年

3 鄧靖;固體熱載體法褐煤熱解及產(chǎn)物特性的研究[D];太原理工大學(xué);2013年

，

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