【摘要】：褐煤的脫水提質(zhì)技術(shù)能夠提高煤炭利用效率、降低能耗損失,已經(jīng)成為低品質(zhì)煤大規(guī)模利用的重點(diǎn)發(fā)展方向。水熱改性作為一種高效、實(shí)用的脫水提質(zhì)手段成為研究的熱點(diǎn)問(wèn)題。本文就水熱改性對(duì)三種低品質(zhì)煤熱轉(zhuǎn)化過(guò)程中氮、硫污染物釋放及遷移影響規(guī)律進(jìn)行了研究。 首先采用高溫高壓反應(yīng)釜對(duì)準(zhǔn)東煙煤、伊敏褐煤、昭通褐煤進(jìn)行了200℃、250℃、300℃的水熱改性實(shí)驗(yàn),獲取改性后煤樣。發(fā)現(xiàn)水熱改性確實(shí)大幅度脫除了煤中水份,提高了低位燃燒熱值。 (1)利用X射線光電子能譜技術(shù)(XPS)對(duì)水熱改性前后三種煤種氮、硫元素的賦存形態(tài)進(jìn)行了研究,利用XPSPEAK分峰軟件進(jìn)行氮、硫元素的分峰擬合。發(fā)現(xiàn)水熱改性確實(shí)破壞了煤中氮、硫官能團(tuán)結(jié)構(gòu),使得煤中的N-5向N-6或者N-Q發(fā)生轉(zhuǎn)化,多環(huán)芳烴結(jié)構(gòu)的N-Q向N-6轉(zhuǎn)化,煤分子邊緣的N-Q向N-X轉(zhuǎn)化；硫醇硫醚、亞砜、砜類硫可能會(huì)向噻吩轉(zhuǎn)化,硫醇硫醚可能向硫鐵礦硫轉(zhuǎn)化,同時(shí)可能存在著砜類、亞砜類硫向硫酸鹽硫轉(zhuǎn)化的過(guò)程。 (2)利用快速熱解儀器-質(zhì)譜色譜聯(lián)用儀(Py-GC/MS)對(duì)三種低品質(zhì)煤改性前后快速熱解時(shí)含氮、硫大分子揮發(fā)份的釋放特性進(jìn)行了研究,發(fā)現(xiàn)水熱改性影響了煤改性前后氮、硫大分子的種類和釋放含量。將氮、硫大分子揮發(fā)份歸類后發(fā)現(xiàn),水熱改性影響了揮發(fā)份中含氮物質(zhì)如胺類、酰胺類、肟類、腈類、唑類,含硫物質(zhì)如硫醇硫醚類等的釋放特性。 (3)利用管式爐實(shí)驗(yàn)平臺(tái)對(duì)三種低品質(zhì)煤改性前后熱解、燃燒過(guò)程中含氮、硫雜質(zhì)的污染物釋放特性進(jìn)行了研究。水熱改性使得熱解過(guò)程中準(zhǔn)東煤及昭通煤含氮、硫污染物的釋放減少,使得伊敏煤含氮污染物釋放增加、含硫污染物釋放減小。水熱改性使得燃燒過(guò)程中準(zhǔn)東煤含氮污染物釋放減少,含硫污染物釋放增大,伊敏煤含氮污染物釋放增大、含硫污染物釋放減小,昭通煤NO釋放量增大,S02第一釋放峰降低第二釋放峰升高。
[Abstract]:The dehydration technology of lignite can improve the efficiency of coal utilization and reduce the loss of energy consumption, which has become the key direction of large-scale utilization of low-quality coal. As an efficient and practical method of dehydration and quality improvement, hydrothermal modification has become a hot issue. In this paper, the effects of hydrothermal modification on the release and migration of nitrogen and sulfur pollutants in the process of thermal conversion of three kinds of low-quality coal were studied. Firstly, the experiments of hydrothermal modification of Dong bituminous coal, Yimin lignite and Zhaotong lignite were carried out at 200 鈩，

本文編號(hào)：2154749