成都合成鎂鈣砂的煅燒工藝和煅燒設備
發布(bu)日期:2022-01-21 瀏覽次數:34742目前我國生產成都合成鎂鈣砂所使用(yong)(yong)的(de)原(yuan)料(liao)有菱(ling)鎂(mei)石(shi)、白(bai)云(yun)石(shi)和(he)石(shi)灰(hui)石(shi)。所采用(yong)(yong)的(de)工(gong)(gong)藝(yi)為二(er)步煅(duan)(duan)(duan)(duan)燒、入工(gong)(gong)合成(cheng)工(gong)(gong)藝(yi)。即先將菱(ling)鎂(mei)石(shi)、白(bai)云(yun)石(shi)和(he)石(shi)灰(hui)石(shi)在(zai)較(jiao)低的(de)溫(wen)度(du)下輕燒,生(sheng)產出(chu)輕燒氧(yang)化(hua)鎂(mei)、輕燒白(bai)云(yun)石(shi)和(he)生(sheng)石(shi)灰(hui)。然后進行配料(liao)、磨細、混料(liao)、成(cheng)型(xing),最后經過高(gao)溫(wen)煅(duan)(duan)(duan)(duan)燒,煅(duan)(duan)(duan)(duan)燒出(chu)不同牌號的(de)合成(cheng)鎂(mei)鈣砂。具(ju)體的(de)煅(duan)(duan)(duan)(duan)燒工(gong)(gong)藝(yi)有半(ban)干法壓(ya)坯(pi)、隧道窯煅(duan)(duan)(duan)(duan)燒工(gong)(gong)藝(yi);半(ban)干法壓(ya)球(qiu)、焦炭豎窯煅(duan)(duan)(duan)(duan)燒工(gong)(gong)藝(yi);干法壓(ya)球(qiu)、高(gao)溫(wen)燃油豎窯和(he)回轉窯煅(duan)(duan)(duan)(duan)燒工(gong)(gong)藝(yi)。
1、半干法(fa)壓坯、隧道窯煅(duan)燒工藝該(gai)煅(duan)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(ban)干(gan)法壓(ya)球、焦炭豎(shu)窯煅燒工藝
該煅(duan)燒(shao)(shao)工藝生產(chan)(chan)(chan)(chan)合成鎂鈣(gai)砂是以(yi)(yi)輕(qing)(qing)(qing)燒(shao)(shao)白云(yun)石(shi)和(he)(he)輕(qing)(qing)(qing)燒(shao)(shao)氧化鎂為原料。將輕(qing)(qing)(qing)燒(shao)(shao)白云(yun)石(shi)和(he)(he)輕(qing)(qing)(qing)燒(shao)(shao)氧化鎂分(fen)別磨成細(xi)粉,計量后按比例加入輪碾機(ji)中再加水混合,混好的(de)(de)合成料在雙輥壓(ya)球機(ji)上壓(ya)成料球,干(gan)燥后裝入以(yi)(yi)焦(jiao)炭(tan)或無煙(yan)煤為燃料的(de)(de)豎窯(yao)內煅(duan)燒(shao)(shao)。裝料方式是焦(jiao)炭(tan)或無煙(yan)煤和(he)(he)料球分(fen)層裝入。我國(guo)遼寧(ning)省(sheng)生產(chan)(chan)(chan)(chan)合成鎂鈣(gai)砂的(de)(de)企業中,大部(bu)分(fen)采用(yong)該煅(duan)燒(shao)(shao)工藝。所用(yong)豎窯(yao)的(de)(de)規格一(yi)般(ban)為3m×16m。該煅(duan)燒(shao)(shao)工藝簡單,產(chan)(chan)(chan)(chan)品(pin)(pin)成本低,但(dan)在煅(duan)燒(shao)(shao)過程中料球和(he)(he)焦(jiao)炭(tan)混在一(yi)起,焦(jiao)炭(tan)燃燒(shao)(shao)產(chan)(chan)(chan)(chan)生的(de)(de)灰分(fen)有一(yi)部(bu)分(fen)混入到料球中,增加了產(chan)(chan)(chan)(chan)品(pin)(pin)的(de)(de)雜質含量。
3、干法(fa)壓球、燃油豎窯煅燒工藝
該(gai)(gai)煅(duan)(duan)(duan)燒(shao)(shao)(shao)工(gong)藝用(yong)(yong)(yong)(yong)于生(sheng)產(chan)高(gao)純(chun)度(du)合成鎂鈣砂。將(jiang)高(gao)純(chun)度(du)輕燒(shao)(shao)(shao)氧化鎂和輕燒(shao)(shao)(shao)白云石配料(liao)(liao)、混合磨細后,直(zhi)接(jie)將(jiang)干粉料(liao)(liao)送(song)(song)入(ru)高(gao)壓(ya)壓(ya)球(qiu)機中(zhong)干壓(ya)成球(qiu),然后再送(song)(song)入(ru)高(gao)溫燃(ran)油(you)(you)豎窯(yao)內(nei)(nei)煅(duan)(duan)(duan)燒(shao)(shao)(shao)。這種煅(duan)(duan)(duan)燒(shao)(shao)(shao)工(gong)藝的(de)(de)優(you)勢是燃(ran)料(liao)(liao)油(you)(you)噴入(ru)到(dao)料(liao)(liao)層(ceng)內(nei)(nei),在(zai)料(liao)(liao)層(ceng)內(nei)(nei)部(bu)燃(ran)燒(shao)(shao)(shao),煅(duan)(duan)(duan)燒(shao)(shao)(shao)溫度(du)高(gao),可達到(dao)1800℃以上;燃(ran)料(liao)(liao)燃(ran)燒(shao)(shao)(shao)后不產(chan)生(sheng)灰分,對物料(liao)(liao)的(de)(de)純(chun)度(du)沒有影響(xiang)。目前,國內(nei)(nei)采用(yong)(yong)(yong)(yong)該(gai)(gai)煅(duan)(duan)(duan)燒(shao)(shao)(shao)工(gong)藝生(sheng)產(chan)合成鎂鈣砂的(de)(de)企(qi)業,只有南方一家公司。該(gai)(gai)公司燃(ran)油(you)(you)豎窯(yao)的(de)(de)規格為φ1.75m×11.5m,窯(yao)的(de)(de)工(gong)作襯用(yong)(yong)(yong)(yong)高(gao)純(chun)度(du)堿(jian)性耐火制(zhi)品砌筑(zhu),厚度(du)為350mm。工(gong)作襯于窯(yao)體鋼殼之間(jian)用(yong)(yong)(yong)(yong)輕質保(bao)溫磚砌筑(zhu)。以重柴油(you)(you)為燃(ran)料(liao)(liao),煅(duan)(duan)(duan)燒(shao)(shao)(shao)溫度(du)>1800℃。設(she)計4排(pai)燒(shao)(shao)(shao)嘴(zui)(zui),上下布(bu)(bu)置(zhi),間(jian)距900mm。每排(pai)設(she)計16支(zhi)燒(shao)(shao)(shao)嘴(zui)(zui),沿圓周均布(bu)(bu)。采用(yong)(yong)(yong)(yong)無冷卻(que)燒(shao)(shao)(shao)嘴(zui)(zui),每支(zhi)燒(shao)(shao)(shao)嘴(zui)(zui)配一臺計量泵供油(you)(you),一次空氣(qi)由羅茨風(feng)機供應(ying)。實際生(sheng)產(chan)中(zhong)使(shi)用(yong)(yong)(yong)(yong)一排(pai)燒(shao)(shao)(shao)嘴(zui)(zui)。連續裝(zhuang)窯(yao)和出窯(yao),全部(bu)自(zi)動化控制(zhi),生(sheng)產(chan)能力。
4、干法壓球、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。