中国电机工程学报
中國電機工程學報
중국전궤공정학보
ZHONGGUO DIANJI GONGCHENG XUEBAO
2013年
23期
68-74
,共7页
惠贺龙%付兴民%王小华%韦云钊%贾晋炜%舒新前
惠賀龍%付興民%王小華%韋雲釗%賈晉煒%舒新前
혜하룡%부흥민%왕소화%위운쇠%가진위%서신전
洗选%结构%热解%煤焦%灰
洗選%結構%熱解%煤焦%灰
세선%결구%열해%매초%회
coal preparation%structure%pyrolysis%coal char%ash
为了探讨煤炭洗选对煤结构及其热解特性的影响,本文选择贺西煤矿原煤(RC)、精煤(CC)、尾煤(TC)和脱灰煤(DC),利用 X 射线衍射(XRD)及傅里叶红外光谱(FT-IR)分析了洗选前后煤炭的结构变化,通过热重(TG/DTG)实验研究了煤热解特性,并对热解焦微晶结构作出分析。结果表明:煤炭洗选前后主要是灰分变化,对煤炭微晶结构和大分子结构的影响并不明显;从微观角度分析发现洗选造成脂肪富氢程度(Hal/Har)和脂芳氢比降低,特别是化学处理造成脂链上富氢基团(CH3、CH2)的脱落,但对脂链结构没有影响。在煤的热解过程中,灰分的存在降低了煤炭的热解缩聚程度,增加了热解活化能,造成热解特征温度均向高温区推移;并阻碍了煤焦基本晶格单元纵向的热缩聚,抑制了煤焦的石墨化进程。
為瞭探討煤炭洗選對煤結構及其熱解特性的影響,本文選擇賀西煤礦原煤(RC)、精煤(CC)、尾煤(TC)和脫灰煤(DC),利用 X 射線衍射(XRD)及傅裏葉紅外光譜(FT-IR)分析瞭洗選前後煤炭的結構變化,通過熱重(TG/DTG)實驗研究瞭煤熱解特性,併對熱解焦微晶結構作齣分析。結果錶明:煤炭洗選前後主要是灰分變化,對煤炭微晶結構和大分子結構的影響併不明顯;從微觀角度分析髮現洗選造成脂肪富氫程度(Hal/Har)和脂芳氫比降低,特彆是化學處理造成脂鏈上富氫基糰(CH3、CH2)的脫落,但對脂鏈結構沒有影響。在煤的熱解過程中,灰分的存在降低瞭煤炭的熱解縮聚程度,增加瞭熱解活化能,造成熱解特徵溫度均嚮高溫區推移;併阻礙瞭煤焦基本晶格單元縱嚮的熱縮聚,抑製瞭煤焦的石墨化進程。
위료탐토매탄세선대매결구급기열해특성적영향,본문선택하서매광원매(RC)、정매(CC)、미매(TC)화탈회매(DC),이용 X 사선연사(XRD)급부리협홍외광보(FT-IR)분석료세선전후매탄적결구변화,통과열중(TG/DTG)실험연구료매열해특성,병대열해초미정결구작출분석。결과표명:매탄세선전후주요시회분변화,대매탄미정결구화대분자결구적영향병불명현;종미관각도분석발현세선조성지방부경정도(Hal/Har)화지방경비강저,특별시화학처리조성지련상부경기단(CH3、CH2)적탈락,단대지련결구몰유영향。재매적열해과정중,회분적존재강저료매탄적열해축취정도,증가료열해활화능,조성열해특정온도균향고온구추이;병조애료매초기본정격단원종향적열축취,억제료매초적석묵화진정。
The samples of raw coal (RC), clean coal (CC), tailings (TC) and demineralized coal (DC) used in this study were provided by Hexi Coal. The effects of coal preparation on the coal structure and pyrolysis characteristics were investigated by XRD, FT-IR and TG/DTG, and the crystalline structure of pyrolysis char has been analyzed simultaneously in this paper. The results indicate that coal preparation has a notable impact on the ash content of coal and little effect on the microcrystalline structure and macromolecular structure of coal. On a micro level, it was found that coal preparation led to the decrease of aliphatic hydrogen-enriched degree and the ratio of aliphatic hydrocarbon and aromatic hydrocarbon (Hal/Har), especially the loss of hydrogen-enriched group from the aliphatic chain caused by the chemical treatment, while have no effect on chain structures of aliphatic. In the process of coal pyrolysis, the existence of ash reduced the polycondensation degree of the chars, increased the reaction activation energy and pushed the process of the pyrolysis into high temperature scale. Moreover, the ash in chars also hindered the longitudinal coalescence of basic crystalline structure unit, and cramped the progress of char graphitizing.