伊春合成鎂鈣砂的煅燒工藝和煅燒設備
發(fa)布日(ri)期(qi):2022-01-21 瀏覽次數:34701目前我國生產伊春合成鎂鈣砂所使用的原(yuan)料有(you)菱鎂石(shi)(shi)、白(bai)云(yun)(yun)石(shi)(shi)和(he)(he)石(shi)(shi)灰(hui)石(shi)(shi)。所采用的工(gong)(gong)藝為二步煅(duan)(duan)燒(shao)(shao)、入(ru)工(gong)(gong)合(he)成工(gong)(gong)藝。即(ji)先將菱鎂石(shi)(shi)、白(bai)云(yun)(yun)石(shi)(shi)和(he)(he)石(shi)(shi)灰(hui)石(shi)(shi)在較低的溫(wen)度下輕燒(shao)(shao),生產(chan)出輕燒(shao)(shao)氧化鎂、輕燒(shao)(shao)白(bai)云(yun)(yun)石(shi)(shi)和(he)(he)生石(shi)(shi)灰(hui)。然后(hou)進行配(pei)料、磨細(xi)、混料、成型,最后(hou)經過高溫(wen)煅(duan)(duan)燒(shao)(shao),煅(duan)(duan)燒(shao)(shao)出不同牌(pai)號的合(he)成鎂鈣砂。具體(ti)的煅(duan)(duan)燒(shao)(shao)工(gong)(gong)藝有(you)半干法(fa)壓(ya)(ya)坯(pi)、隧道窯(yao)煅(duan)(duan)燒(shao)(shao)工(gong)(gong)藝;半干法(fa)壓(ya)(ya)球、焦(jiao)炭(tan)豎窯(yao)煅(duan)(duan)燒(shao)(shao)工(gong)(gong)藝;干法(fa)壓(ya)(ya)球、高溫(wen)燃油豎窯(yao)和(he)(he)回轉窯(yao)煅(duan)(duan)燒(shao)(shao)工(gong)(gong)藝。
1、半干(gan)法壓坯、隧道窯煅燒(shao)(shao)工藝該煅燒(shao)(shao)工藝
生產合成鎂鈣砂是以生石灰和輕燒氧化鎂為原料。首先將生石灰加水消化成消石灰,然后將消石灰與輕燒氧化鎂配料,經過攪拌混合,入筒磨機內共同磨細、均化,再將磨細的合成料在輪碾機內加水混合成半干料,在摩擦壓力機上壓成具有一定外形尺寸的磚坯,經過干燥,裝于隧道窯車上,推入隧道窯內高溫煅燒成合成鎂鈣砂熟料。我國某公司煅燒合成鎂鈣砂使用的隧道窯規格為104.5m×2.0m×1.2m,共52個車位,以熱發生爐煤氣為燃料,設12對套管式煤氣燒嘴,煅燒溫度1620~1650℃,年產量1.5萬t。以隧道窯作為煅燒設備煅燒溫度均勻,保溫時間長,物料達到充分燒結。因此,可獲得高致密度的合成耐火原料。
2、半干法壓球、焦炭豎(shu)窯煅燒工藝
該(gai)煅(duan)燒(shao)(shao)工(gong)藝生(sheng)產(chan)(chan)合(he)成(cheng)(cheng)(cheng)鎂鈣砂(sha)是以輕燒(shao)(shao)白云石和(he)輕燒(shao)(shao)氧化(hua)鎂為原料。將輕燒(shao)(shao)白云石和(he)輕燒(shao)(shao)氧化(hua)鎂分(fen)(fen)(fen)別磨成(cheng)(cheng)(cheng)細粉,計(ji)量后按比例加入輪碾機中(zhong)再(zai)加水混(hun)(hun)(hun)合(he),混(hun)(hun)(hun)好(hao)的(de)合(he)成(cheng)(cheng)(cheng)料在(zai)雙輥(gun)壓(ya)球(qiu)(qiu)(qiu)機上壓(ya)成(cheng)(cheng)(cheng)料球(qiu)(qiu)(qiu),干燥后裝(zhuang)(zhuang)入以焦炭或(huo)無煙(yan)煤(mei)為燃(ran)料的(de)豎窯內煅(duan)燒(shao)(shao)。裝(zhuang)(zhuang)料方式是焦炭或(huo)無煙(yan)煤(mei)和(he)料球(qiu)(qiu)(qiu)分(fen)(fen)(fen)層裝(zhuang)(zhuang)入。我國遼寧省生(sheng)產(chan)(chan)合(he)成(cheng)(cheng)(cheng)鎂鈣砂(sha)的(de)企業中(zhong),大部(bu)分(fen)(fen)(fen)采用(yong)該(gai)煅(duan)燒(shao)(shao)工(gong)藝。所用(yong)豎窯的(de)規格一(yi)般為3m×16m。該(gai)煅(duan)燒(shao)(shao)工(gong)藝簡(jian)單,產(chan)(chan)品成(cheng)(cheng)(cheng)本低,但(dan)在(zai)煅(duan)燒(shao)(shao)過程中(zhong)料球(qiu)(qiu)(qiu)和(he)焦炭混(hun)(hun)(hun)在(zai)一(yi)起,焦炭燃(ran)燒(shao)(shao)產(chan)(chan)生(sheng)的(de)灰分(fen)(fen)(fen)有一(yi)部(bu)分(fen)(fen)(fen)混(hun)(hun)(hun)入到料球(qiu)(qiu)(qiu)中(zhong),增加了產(chan)(chan)品的(de)雜質含量。
3、干法壓(ya)球、燃(ran)油(you)豎窯(yao)煅燒工(gong)藝
該煅(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝用(yong)(yong)于生產高(gao)(gao)(gao)純(chun)度(du)(du)合(he)成(cheng)鎂(mei)鈣砂。將(jiang)高(gao)(gao)(gao)純(chun)度(du)(du)輕(qing)燒(shao)(shao)(shao)氧(yang)化鎂(mei)和(he)輕(qing)燒(shao)(shao)(shao)白云石配料(liao)(liao)、混合(he)磨細后,直接將(jiang)干粉料(liao)(liao)送入(ru)高(gao)(gao)(gao)壓(ya)(ya)壓(ya)(ya)球機(ji)中(zhong)干壓(ya)(ya)成(cheng)球,然后再送入(ru)高(gao)(gao)(gao)溫燃油豎窯(yao)(yao)內(nei)煅(duan)燒(shao)(shao)(shao)。這(zhe)種煅(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝的(de)優勢是燃料(liao)(liao)油噴入(ru)到料(liao)(liao)層內(nei),在料(liao)(liao)層內(nei)部燃燒(shao)(shao)(shao),煅(duan)燒(shao)(shao)(shao)溫度(du)(du)高(gao)(gao)(gao),可達到1800℃以上(shang);燃料(liao)(liao)燃燒(shao)(shao)(shao)后不產生灰分,對物料(liao)(liao)的(de)純(chun)度(du)(du)沒有影響。目前(qian),國內(nei)采(cai)用(yong)(yong)該煅(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝生產合(he)成(cheng)鎂(mei)鈣砂的(de)企業,只有南方(fang)一(yi)(yi)(yi)家公(gong)司(si)。該公(gong)司(si)燃油豎窯(yao)(yao)的(de)規格為φ1.75m×11.5m,窯(yao)(yao)的(de)工(gong)(gong)(gong)作襯用(yong)(yong)高(gao)(gao)(gao)純(chun)度(du)(du)堿性耐火制品砌(qi)筑,厚(hou)度(du)(du)為350mm。工(gong)(gong)(gong)作襯于窯(yao)(yao)體(ti)鋼殼(ke)之間用(yong)(yong)輕(qing)質(zhi)保溫磚砌(qi)筑。以重(zhong)柴油為燃料(liao)(liao),煅(duan)燒(shao)(shao)(shao)溫度(du)(du)>1800℃。設(she)計(ji)(ji)(ji)4排燒(shao)(shao)(shao)嘴,上(shang)下布(bu)置,間距900mm。每排設(she)計(ji)(ji)(ji)16支燒(shao)(shao)(shao)嘴,沿圓周均布(bu)。采(cai)用(yong)(yong)無冷卻燒(shao)(shao)(shao)嘴,每支燒(shao)(shao)(shao)嘴配一(yi)(yi)(yi)臺計(ji)(ji)(ji)量泵供油,一(yi)(yi)(yi)次空氣由羅茨(ci)風(feng)機(ji)供應。實(shi)際生產中(zhong)使用(yong)(yong)一(yi)(yi)(yi)排燒(shao)(shao)(shao)嘴。連續裝窯(yao)(yao)和(he)出(chu)窯(yao)(yao),全部自動化控制,生產能(neng)力。
4、干(gan)法壓球(qiu)、回轉(zhuan)窯煅燒工藝(yi)
目前,國內有部分企業采用高溫回轉窯煅燒合成鎂鈣砂。其煅燒工藝為:將高純度輕燒氧化鎂和高純度輕燒白云石按比例配料后,經過攪拌昆合,磨成細粉,送入高壓壓球機中干壓成球,然后送入高溫回轉窯內煅燒。如某公司采用φ2.5m×60m超高溫回轉窯煅燒合成鎂鈣砂,以重油作燃料,采用機械霧化燒嘴,窯尾設煙氣換熱器,將一次空氣預熱到450~500℃,煅燒溫度>1850℃。煅燒CaO含量20%~30%合成鎂鈣砂,產量2~2.5t/h,油耗300kg/t。