菏澤合成鎂鈣砂的煅燒工藝和煅燒設備
發布日期(qi):2022-01-21 瀏覽次數:34946目前我國生產菏澤合成鎂鈣砂所使用的(de)原(yuan)料有菱(ling)鎂石(shi)(shi)(shi)(shi)(shi)、白(bai)云(yun)石(shi)(shi)(shi)(shi)(shi)和(he)石(shi)(shi)(shi)(shi)(shi)灰(hui)石(shi)(shi)(shi)(shi)(shi)。所采(cai)用的(de)工(gong)藝(yi)(yi)(yi)(yi)為二步煅(duan)(duan)(duan)燒(shao)(shao)、入工(gong)合成工(gong)藝(yi)(yi)(yi)(yi)。即先將(jiang)菱(ling)鎂石(shi)(shi)(shi)(shi)(shi)、白(bai)云(yun)石(shi)(shi)(shi)(shi)(shi)和(he)石(shi)(shi)(shi)(shi)(shi)灰(hui)石(shi)(shi)(shi)(shi)(shi)在較低的(de)溫度下(xia)輕(qing)燒(shao)(shao),生產出輕(qing)燒(shao)(shao)氧(yang)化(hua)鎂、輕(qing)燒(shao)(shao)白(bai)云(yun)石(shi)(shi)(shi)(shi)(shi)和(he)生石(shi)(shi)(shi)(shi)(shi)灰(hui)。然后(hou)進行配料、磨細(xi)、混料、成型,最后(hou)經過高(gao)溫煅(duan)(duan)(duan)燒(shao)(shao),煅(duan)(duan)(duan)燒(shao)(shao)出不(bu)同牌號的(de)合成鎂鈣砂。具體的(de)煅(duan)(duan)(duan)燒(shao)(shao)工(gong)藝(yi)(yi)(yi)(yi)有半干(gan)法(fa)壓坯、隧道(dao)窯煅(duan)(duan)(duan)燒(shao)(shao)工(gong)藝(yi)(yi)(yi)(yi);半干(gan)法(fa)壓球、焦(jiao)炭豎窯煅(duan)(duan)(duan)燒(shao)(shao)工(gong)藝(yi)(yi)(yi)(yi);干(gan)法(fa)壓球、高(gao)溫燃油豎窯和(he)回轉窯煅(duan)(duan)(duan)燒(shao)(shao)工(gong)藝(yi)(yi)(yi)(yi)。
1、半干法壓坯、隧道窯煅燒工藝該煅燒工藝
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(gan)法壓球、焦炭豎窯煅燒工藝(yi)
該煅燒(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)生產(chan)合成(cheng)(cheng)鎂(mei)鈣砂(sha)是以(yi)輕燒(shao)(shao)(shao)(shao)白云石和(he)輕燒(shao)(shao)(shao)(shao)氧化鎂(mei)為(wei)(wei)原料(liao)(liao)。將輕燒(shao)(shao)(shao)(shao)白云石和(he)輕燒(shao)(shao)(shao)(shao)氧化鎂(mei)分(fen)(fen)別磨成(cheng)(cheng)細粉,計量后按比(bi)例加入(ru)輪碾機(ji)中再(zai)加水混(hun)合,混(hun)好的(de)合成(cheng)(cheng)料(liao)(liao)在(zai)(zai)雙輥壓球(qiu)(qiu)機(ji)上壓成(cheng)(cheng)料(liao)(liao)球(qiu)(qiu),干燥后裝入(ru)以(yi)焦(jiao)(jiao)炭或(huo)無(wu)煙(yan)煤(mei)為(wei)(wei)燃(ran)料(liao)(liao)的(de)豎窯(yao)內煅燒(shao)(shao)(shao)(shao)。裝料(liao)(liao)方式是焦(jiao)(jiao)炭或(huo)無(wu)煙(yan)煤(mei)和(he)料(liao)(liao)球(qiu)(qiu)分(fen)(fen)層(ceng)裝入(ru)。我國遼寧(ning)省生產(chan)合成(cheng)(cheng)鎂(mei)鈣砂(sha)的(de)企業(ye)中,大部(bu)分(fen)(fen)采用(yong)該煅燒(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)。所(suo)用(yong)豎窯(yao)的(de)規格一般為(wei)(wei)3m×16m。該煅燒(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)簡單,產(chan)品成(cheng)(cheng)本低,但在(zai)(zai)煅燒(shao)(shao)(shao)(shao)過(guo)程中料(liao)(liao)球(qiu)(qiu)和(he)焦(jiao)(jiao)炭混(hun)在(zai)(zai)一起,焦(jiao)(jiao)炭燃(ran)燒(shao)(shao)(shao)(shao)產(chan)生的(de)灰分(fen)(fen)有(you)一部(bu)分(fen)(fen)混(hun)入(ru)到料(liao)(liao)球(qiu)(qiu)中,增加了產(chan)品的(de)雜質含(han)量。
3、干法壓球(qiu)、燃(ran)油豎窯煅(duan)燒工藝
該煅燒(shao)(shao)工(gong)(gong)藝用(yong)于生產(chan)高(gao)純度(du)(du)合(he)成鎂鈣砂。將高(gao)純度(du)(du)輕(qing)燒(shao)(shao)氧化鎂和輕(qing)燒(shao)(shao)白云石配料(liao)(liao)、混合(he)磨細后,直接將干(gan)(gan)粉料(liao)(liao)送(song)(song)入高(gao)壓(ya)壓(ya)球機(ji)中干(gan)(gan)壓(ya)成球,然后再(zai)送(song)(song)入高(gao)溫燃(ran)油(you)(you)豎窯內(nei)煅燒(shao)(shao)。這種煅燒(shao)(shao)工(gong)(gong)藝的優勢是燃(ran)料(liao)(liao)油(you)(you)噴(pen)入到(dao)料(liao)(liao)層內(nei),在料(liao)(liao)層內(nei)部燃(ran)燒(shao)(shao),煅燒(shao)(shao)溫度(du)(du)高(gao),可達到(dao)1800℃以上;燃(ran)料(liao)(liao)燃(ran)燒(shao)(shao)后不(bu)產(chan)生灰(hui)分,對物料(liao)(liao)的純度(du)(du)沒有影(ying)響(xiang)。目(mu)前,國內(nei)采用(yong)該煅燒(shao)(shao)工(gong)(gong)藝生產(chan)合(he)成鎂鈣砂的企業,只(zhi)有南(nan)方一(yi)家公(gong)司。該公(gong)司燃(ran)油(you)(you)豎窯的規格為φ1.75m×11.5m,窯的工(gong)(gong)作襯(chen)(chen)用(yong)高(gao)純度(du)(du)堿性(xing)耐火(huo)制(zhi)(zhi)品砌筑,厚度(du)(du)為350mm。工(gong)(gong)作襯(chen)(chen)于窯體鋼(gang)殼之間用(yong)輕(qing)質保溫磚(zhuan)砌筑。以重柴(chai)油(you)(you)為燃(ran)料(liao)(liao),煅燒(shao)(shao)溫度(du)(du)>1800℃。設計4排燒(shao)(shao)嘴,上下布置,間距900mm。每排設計16支燒(shao)(shao)嘴,沿圓周(zhou)均布。采用(yong)無冷卻燒(shao)(shao)嘴,每支燒(shao)(shao)嘴配一(yi)臺計量(liang)泵供(gong)油(you)(you),一(yi)次空氣由羅茨風機(ji)供(gong)應(ying)。實(shi)際生產(chan)中使用(yong)一(yi)排燒(shao)(shao)嘴。連續裝窯和出窯,全部自動化控制(zhi)(zhi),生產(chan)能力(li)。
4、干法壓球、回轉窯煅燒工藝
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。