yongyuyejinshengchandelantanhuizaiganliuluneishoudaohuilumeiqiranshaoheshixijiaochanshengdeshuizhengqideyingxiang。weimingqueshuizhengqiduilantankongxijiegoujiliuhanliangdeyingxiang,xuanqumoudijiemeizaibutongrejietiaojianxiajinxingrejieshiyan,kaochabutongrejiezhongwen(500~900 ℃)和水蒸氣通入量(質量分數為0、20%、40%、60%)對低階煤熱解產物中硫含量的影響。采用比表麵及孔徑分析儀和定硫儀分析了蘭炭孔隙結構及蘭炭中全硫相對含量的變化,采用X射線光電子能譜對蘭炭表麵含硫官能團的賦存形態進行了分析。試驗結果表明,在惰性氣氛下,當溫度成為限製性環節時,中低溫(500~700 ℃)條件下硫的脫除效果較好,熱解終溫進一步升高則不利於硫的脫除。當在熱解過程中通入水蒸氣時,低溫條件下(500~600 ℃),少量(20%)水蒸氣脫硫顯著,大量(40%~60%)水蒸氣則不利於脫硫,此時不同形式的硫會出現相互轉化的情況,水蒸氣促使硫主要以氣相形式析出。較高溫度條件下(700~800 ℃)水shui蒸zheng氣qi雖sui促cu進jin孔kong隙xi結jie構gou發fa育yu,但dan硫liu無wu法fa以yi氣qi相xiang形xing式shi析xi出chu,水shui蒸zheng氣qi和he縮suo聚ju反fan應ying共gong同tong作zuo用yong下xia使shi硫liu主zhu要yao在zai固gu相xiang中zhong進jin行xing轉zhuan化hua,從cong而er導dao致zhi脫tuo硫liu率lv降jiang低di。高gao溫wen條tiao件jian下xia(900 ℃)水(shui)蒸(zheng)氣(qi)對(dui)孔(kong)隙(xi)結(jie)構(gou)破(po)壞(huai)嚴(yan)重(zhong),使(shi)硫(liu)主(zhu)要(yao)以(yi)氣(qi)相(xiang)形(xing)式(shi)析(xi)出(chu),顯(xian)著(zhu)提(ti)高(gao)脫(tuo)硫(liu)率(lv),但(dan)會(hui)生(sheng)成(cheng)部(bu)分(fen)無(wu)機(ji)硫(liu)和(he)較(jiao)難(nan)分(fen)解(jie)的(de)有(you)機(ji)硫(liu)。因(yin)此(ci),在(zai)幹(gan)餾(liu)爐(lu)生(sheng)產(chan)蘭(lan)炭(tan)的(de)過(guo)程(cheng)中(zhong),應(ying)嚴(yan)格(ge)控(kong)製(zhi)中(zhong)高(gao)溫(wen)區(qu)域(yu)生(sheng)產(chan)流(liu)程(cheng),避(bi)免(mian)水(shui)蒸(zheng)氣(qi)的(de)進(jin)入(ru),在(zai)低(di)溫(wen)區(qu)域(yu)的(de)水(shui)蒸(zheng)氣(qi)添(tian)加(jia)量(liang)也(ye)應(ying)盡(jin)量(liang)控(kong)製(zhi)在(zai)20%以內。
02
關 鍵 詞
蘭炭;熱解;水蒸氣;硫形態;脫硫率;X射線光電子能譜
03
引 言
蘭炭作為煤熱解的固相產物之一,因其具有低灰低硫的特點,近年來逐步應用於高爐、tiehejindenggangtieyejinlingyu。yidijiemeiweiyuanliaoshengchanlantanderejieguochengzhuyaozaiganliuluneijinxing,ganliuludibudehuilumeiqiranshaoheshixijiaochanshengdeshuizhengqihuishangshengzhirejieduan,duichuyurejieduanlantandekongxijiegoujiliudeqianyizhuanhuaguochengchanshengyingxiang。liuzaimeirejieguochengzhongdeqianyijizhiyuwendu、氣qi氛fen等deng熱re解jie條tiao件jian密mi切qie相xiang關guan,通tong過guo改gai變bian熱re解jie條tiao件jian,探tan究jiu煤mei中zhong各ge含han硫liu官guan能neng團tuan的de轉zhuan化hua行xing為wei,探tan索suo硫liu的de遷qian移yi機ji製zhi,從cong而er達da到dao脫tuo硫liu的de效xiao果guo,對dui煤mei的de清qing潔jie生sheng產chan及ji應ying用yong具ju有you重zhong要yao意yi義yi。
目前,已有學者對煤熱解過程中溫度及水蒸氣對硫的影響進行了研究。部分研究發現,隨著熱解溫度的升高,大部分無機硫、亞碸型硫和碸型硫會被脫除,以H2S、SO2、COS的形式逸出到氣相中,而穩定的噻吩硫則在較高溫度下才開始分解,且存在二次生成的情況。李梅等通過XPS(X射線光電子能譜)對高硫煉焦煤熱解過程中有機硫賦存形態變化規律的研究發現,脫除礦物後有機硫以有機硫化物硫、噻吩硫和亞碸硫這3種存在形式,證明這3種有機硫存在形式更為穩定。文獻進一步對Rasa煤中分布的有機硫利用XPS進行了研究發現,無機硫分解產生的H2S捕(bu)獲(huo)有(you)機(ji)基(ji)質(zhi)形(xing)成(cheng)有(you)機(ji)硫(liu),不(bu)同(tong)有(you)機(ji)硫(liu)之(zhi)間(jian)存(cun)在(zai)相(xiang)互(hu)轉(zhuan)化(hua)的(de)情(qing)況(kuang),且(qie)主(zhu)要(yao)向(xiang)更(geng)穩(wen)定(ding)的(de)噻(sai)吩(fen)類(lei)硫(liu)化(hua)物(wu)轉(zhuan)化(hua)。可(ke)見(jian),噻(sai)吩(fen)硫(liu)的(de)難(nan)以(yi)脫(tuo)除(chu)是(shi)影(ying)響(xiang)煤(mei)脫(tuo)硫(liu)的(de)主(zhu)要(yao)原(yuan)因(yin)之(zhi)一(yi)。HU H Q等利用GC-MSdengduisaifenliuhuahewujinxinglefenxi,jieguobiaoming,suizhewendudezengjiasaifenleiliuhuichuxianjiangdidequshi,shuomingtigaorejiewenduyouliyuliudetuochu。chuwenduyingxiangwai,shuizhengqidecunzaijinyibuzengjialerejieguochengzhongliusuiwendubianhuadefuzaxing。xujunjiedengzaibutongrejietixixiaduiyoujiliudeyanjiufaxian,shuifenziduiyoujiliuderejiejuyouyidingdeyingxiang。WANG M等deng將jiang煤mei在zai水shui蒸zheng氣qi和he氬ya氣qi氛fen下xia進jin行xing熱re解jie,發fa現xian水shui蒸zheng氣qi能neng夠gou促cu進jin噻sai吩fen硫liu化hua合he物wu分fen解jie。部bu分fen學xue者zhe認ren為wei在zai水shui分fen子zi的de影ying響xiang下xia,噻sai吩fen的de硫liu原yuan子zi發fa生sheng質zhi子zi化hua,水shui分fen子zi通tong過guo攻gong擊ji質zhi子zi化hua中zhong間jian體ti從cong而er降jiang低di噻sai吩fen環huan開kai環huan的de難nan度du。NAG N K通過對煤加H2O熱解試驗,發現氫原子通過降低C—S鍵(jian)強(qiang)度(du)促(cu)進(jin)噻(sai)吩(fen)分(fen)解(jie)。由(you)前(qian)人(ren)研(yan)究(jiu)結(jie)果(guo)可(ke)知(zhi),煤(mei)熱(re)解(jie)過(guo)程(cheng)中(zhong)硫(liu)的(de)遷(qian)移(yi)轉(zhuan)化(hua)行(xing)為(wei)十(shi)分(fen)複(fu)雜(za),目(mu)前(qian)研(yan)究(jiu)大(da)多(duo)僅(jin)表(biao)明(ming)了(le)水(shui)蒸(zheng)氣(qi)對(dui)煤(mei)中(zhong)噻(sai)吩(fen)硫(liu)的(de)分(fen)解(jie)有(you)促(cu)進(jin)作(zuo)用(yong),但(dan)在(zai)較(jiao)高(gao)水(shui)蒸(zheng)氣(qi)添(tian)加(jia)量(liang)及(ji)溫(wen)度(du)的(de)共(gong)同(tong)作(zuo)用(yong)下(xia),煤(mei)中(zhong)硫(liu)的(de)遷(qian)移(yi)行(xing)為(wei)研(yan)究(jiu)較(jiao)少(shao)。
gongyelantanzhongdeliuhanliangshiqipinzhidezhongyaohengliangzhibiaozhiyi,shuizhengqiduilantanshengchanguochengzhongliuhanliangdeyingxiangshangweidedaozhongshi。weitanjiushuizhengqitianjialiangduilantanshengchanguochengzhongwujiliuheyoujiliubianhuaguilvdeyingxiang,benwenliyongX射(she)線(xian)光(guang)電(dian)子(zi)能(neng)譜(pu)和(he)定(ding)硫(liu)儀(yi)對(dui)蘭(lan)炭(tan)中(zhong)硫(liu)的(de)賦(fu)存(cun)形(xing)態(tai)及(ji)脫(tuo)硫(liu)率(lv)的(de)變(bian)化(hua)規(gui)律(lv)進(jin)行(xing)研(yan)究(jiu),並(bing)結(jie)合(he)孔(kong)隙(xi)結(jie)構(gou)變(bian)化(hua),探(tan)究(jiu)水(shui)蒸(zheng)氣(qi)添(tian)加(jia)量(liang)和(he)溫(wen)度(du)對(dui)煤(mei)熱(re)解(jie)過(guo)程(cheng)中(zhong)硫(liu)遷(qian)移(yi)的(de)影(ying)響(xiang),從(cong)而(er)為(wei)蘭(lan)炭(tan)的(de)實(shi)際(ji)生(sheng)產(chan)過(guo)程(cheng)控(kong)製(zhi)提(ti)供(gong)理(li)論(lun)依(yi)據(ju)。
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精 選 圖 表

05
結 論
1)在蘭炭熱解過程中,熱解終溫越高並不能有效脫硫。低溫熱解時,少量(20%)水蒸氣通入能有效脫硫,大量(40%~60%)則會導致孔隙堵塞從而不利於硫的脫除。
2)較高溫度(700~800 ℃)熱解時,水蒸氣的通入對硫的脫除有不利影響,且蘭炭中硫以難以分解的硫化物形式存在,蘭炭中的硫難以進一步通過其他方式去除。
3)高溫條件下(900 ℃),水蒸氣添加量增加雖然會促進硫化物的脫除,但對孔隙結構的破壞十分顯著,在生產過程中應盡量避免。
4)綜zong合he考kao慮lv熱re解jie條tiao件jian對dui蘭lan炭tan孔kong隙xi結jie構gou和he熱re解jie過guo程cheng硫liu元yuan素su遷qian移yi的de影ying響xiang,在zai幹gan餾liu爐lu生sheng產chan蘭lan炭tan的de過guo程cheng中zhong,應ying避bi免mian回hui爐lu煤mei氣qi燃ran燒shao和he濕shi熄xi焦jiao產chan生sheng的de水shui蒸zheng氣qi進jin入ru中zhong高gao溫wen區qu域yu,低di溫wen區qu域yu的de水shui蒸zheng氣qi質zhi量liang分fen數shu也ye應ying盡jin量liang控kong製zhi在zai20%以內。
來源:《鋼鐵》2023年第8期