郴州合成鎂鈣砂的煅燒工藝和煅燒設備
發布日期:2022-01-21 瀏覽次數:36132目前我國生產郴州合成鎂鈣砂所(suo)使(shi)用(yong)的(de)原(yuan)料(liao)有(you)(you)菱(ling)鎂(mei)石(shi)(shi)、白(bai)云石(shi)(shi)和(he)石(shi)(shi)灰(hui)石(shi)(shi)。所(suo)采用(yong)的(de)工(gong)(gong)藝(yi)(yi)為二步(bu)煅(duan)燒(shao)(shao)(shao)(shao)(shao)、入工(gong)(gong)合(he)成(cheng)工(gong)(gong)藝(yi)(yi)。即(ji)先(xian)將菱(ling)鎂(mei)石(shi)(shi)、白(bai)云石(shi)(shi)和(he)石(shi)(shi)灰(hui)石(shi)(shi)在較低的(de)溫(wen)度下輕(qing)燒(shao)(shao)(shao)(shao)(shao),生產出輕(qing)燒(shao)(shao)(shao)(shao)(shao)氧(yang)化鎂(mei)、輕(qing)燒(shao)(shao)(shao)(shao)(shao)白(bai)云石(shi)(shi)和(he)生石(shi)(shi)灰(hui)。然后(hou)進行配料(liao)、磨細(xi)、混料(liao)、成(cheng)型,最(zui)后(hou)經過(guo)高(gao)溫(wen)煅(duan)燒(shao)(shao)(shao)(shao)(shao),煅(duan)燒(shao)(shao)(shao)(shao)(shao)出不同牌號的(de)合(he)成(cheng)鎂(mei)鈣砂(sha)。具體的(de)煅(duan)燒(shao)(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)(yi)有(you)(you)半(ban)干(gan)(gan)法(fa)壓坯、隧道窯(yao)(yao)煅(duan)燒(shao)(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)(yi);半(ban)干(gan)(gan)法(fa)壓球、焦炭豎窯(yao)(yao)煅(duan)燒(shao)(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)(yi);干(gan)(gan)法(fa)壓球、高(gao)溫(wen)燃(ran)油豎窯(yao)(yao)和(he)回(hui)轉窯(yao)(yao)煅(duan)燒(shao)(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)(yi)。
1、半干法(fa)壓坯、隧道窯煅燒工(gong)藝該煅燒工(gong)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(jiao)炭豎窯煅燒工藝
該(gai)煅燒(shao)(shao)(shao)(shao)工藝(yi)生產(chan)合(he)成(cheng)鎂(mei)(mei)(mei)鈣(gai)砂是以輕(qing)燒(shao)(shao)(shao)(shao)白(bai)云(yun)石和輕(qing)燒(shao)(shao)(shao)(shao)氧(yang)(yang)化(hua)鎂(mei)(mei)(mei)為原料(liao)(liao)。將輕(qing)燒(shao)(shao)(shao)(shao)白(bai)云(yun)石和輕(qing)燒(shao)(shao)(shao)(shao)氧(yang)(yang)化(hua)鎂(mei)(mei)(mei)分(fen)別磨成(cheng)細(xi)粉,計量后按比例(li)加(jia)入(ru)輪碾(nian)機(ji)(ji)中再加(jia)水混合(he),混好的(de)(de)(de)(de)合(he)成(cheng)料(liao)(liao)在(zai)雙輥壓球(qiu)(qiu)機(ji)(ji)上壓成(cheng)料(liao)(liao)球(qiu)(qiu),干(gan)燥(zao)后裝(zhuang)入(ru)以焦(jiao)炭(tan)或無(wu)煙煤為燃(ran)料(liao)(liao)的(de)(de)(de)(de)豎窯(yao)內煅燒(shao)(shao)(shao)(shao)。裝(zhuang)料(liao)(liao)方式(shi)是焦(jiao)炭(tan)或無(wu)煙煤和料(liao)(liao)球(qiu)(qiu)分(fen)層裝(zhuang)入(ru)。我(wo)國(guo)遼(liao)寧省生產(chan)合(he)成(cheng)鎂(mei)(mei)(mei)鈣(gai)砂的(de)(de)(de)(de)企業中,大部分(fen)采用(yong)該(gai)煅燒(shao)(shao)(shao)(shao)工藝(yi)。所用(yong)豎窯(yao)的(de)(de)(de)(de)規(gui)格一般(ban)為3m×16m。該(gai)煅燒(shao)(shao)(shao)(shao)工藝(yi)簡單,產(chan)品成(cheng)本低,但在(zai)煅燒(shao)(shao)(shao)(shao)過程中料(liao)(liao)球(qiu)(qiu)和焦(jiao)炭(tan)混在(zai)一起(qi),焦(jiao)炭(tan)燃(ran)燒(shao)(shao)(shao)(shao)產(chan)生的(de)(de)(de)(de)灰分(fen)有(you)一部分(fen)混入(ru)到料(liao)(liao)球(qiu)(qiu)中,增加(jia)了產(chan)品的(de)(de)(de)(de)雜質含量。
3、干法(fa)壓球(qiu)、燃油(you)豎窯煅(duan)燒(shao)工藝
該(gai)煅(duan)(duan)(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝用(yong)(yong)(yong)于生(sheng)產(chan)(chan)(chan)高(gao)純度(du)合成(cheng)鎂鈣砂。將高(gao)純度(du)輕燒(shao)(shao)(shao)氧(yang)化鎂和輕燒(shao)(shao)(shao)白云石配料(liao)(liao)(liao)(liao)(liao)(liao)、混合磨細后,直(zhi)接將干(gan)粉料(liao)(liao)(liao)(liao)(liao)(liao)送(song)入高(gao)壓壓球(qiu)(qiu)機中干(gan)壓成(cheng)球(qiu)(qiu),然后再送(song)入高(gao)溫燃(ran)油(you)豎窯內煅(duan)(duan)(duan)燒(shao)(shao)(shao)。這種煅(duan)(duan)(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝的(de)(de)優勢是燃(ran)料(liao)(liao)(liao)(liao)(liao)(liao)油(you)噴入到料(liao)(liao)(liao)(liao)(liao)(liao)層(ceng)內,在料(liao)(liao)(liao)(liao)(liao)(liao)層(ceng)內部(bu)燃(ran)燒(shao)(shao)(shao),煅(duan)(duan)(duan)燒(shao)(shao)(shao)溫度(du)高(gao),可達到1800℃以(yi)上;燃(ran)料(liao)(liao)(liao)(liao)(liao)(liao)燃(ran)燒(shao)(shao)(shao)后不產(chan)(chan)(chan)生(sheng)灰(hui)分,對物料(liao)(liao)(liao)(liao)(liao)(liao)的(de)(de)純度(du)沒有(you)影響。目前(qian),國(guo)內采用(yong)(yong)(yong)該(gai)煅(duan)(duan)(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝生(sheng)產(chan)(chan)(chan)合成(cheng)鎂鈣砂的(de)(de)企業,只有(you)南方一(yi)家(jia)公司。該(gai)公司燃(ran)油(you)豎窯的(de)(de)規格為φ1.75m×11.5m,窯的(de)(de)工(gong)(gong)(gong)作襯用(yong)(yong)(yong)高(gao)純度(du)堿(jian)性耐火(huo)制品砌筑,厚度(du)為350mm。工(gong)(gong)(gong)作襯于窯體鋼殼之間(jian)用(yong)(yong)(yong)輕質保溫磚砌筑。以(yi)重(zhong)柴油(you)為燃(ran)料(liao)(liao)(liao)(liao)(liao)(liao),煅(duan)(duan)(duan)燒(shao)(shao)(shao)溫度(du)>1800℃。設(she)計(ji)4排(pai)燒(shao)(shao)(shao)嘴,上下布(bu)置,間(jian)距900mm。每(mei)排(pai)設(she)計(ji)16支(zhi)(zhi)燒(shao)(shao)(shao)嘴,沿圓周均布(bu)。采用(yong)(yong)(yong)無冷卻燒(shao)(shao)(shao)嘴,每(mei)支(zhi)(zhi)燒(shao)(shao)(shao)嘴配一(yi)臺(tai)計(ji)量泵(beng)供油(you),一(yi)次(ci)空氣由(you)羅茨風機供應。實際生(sheng)產(chan)(chan)(chan)中使用(yong)(yong)(yong)一(yi)排(pai)燒(shao)(shao)(shao)嘴。連續裝窯和出窯,全部(bu)自動化控(kong)制,生(sheng)產(chan)(chan)(chan)能力(li)。
4、干法(fa)壓球、回轉窯煅(duan)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。