東麗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:34973目前我國生產東麗合成鎂鈣砂所使用(yong)的(de)原料(liao)有(you)菱鎂石(shi)(shi)(shi)(shi)(shi)、白云(yun)石(shi)(shi)(shi)(shi)(shi)和(he)(he)石(shi)(shi)(shi)(shi)(shi)灰石(shi)(shi)(shi)(shi)(shi)。所采用(yong)的(de)工(gong)(gong)藝(yi)(yi)為二(er)步煅燒(shao)(shao)、入工(gong)(gong)合(he)成工(gong)(gong)藝(yi)(yi)。即先(xian)將菱鎂石(shi)(shi)(shi)(shi)(shi)、白云(yun)石(shi)(shi)(shi)(shi)(shi)和(he)(he)石(shi)(shi)(shi)(shi)(shi)灰石(shi)(shi)(shi)(shi)(shi)在較低的(de)溫(wen)(wen)度下(xia)輕燒(shao)(shao),生(sheng)產(chan)出輕燒(shao)(shao)氧(yang)化(hua)鎂、輕燒(shao)(shao)白云(yun)石(shi)(shi)(shi)(shi)(shi)和(he)(he)生(sheng)石(shi)(shi)(shi)(shi)(shi)灰。然后進行配料(liao)、磨細、混料(liao)、成型,最后經過高溫(wen)(wen)煅燒(shao)(shao),煅燒(shao)(shao)出不同(tong)牌號的(de)合(he)成鎂鈣砂。具體(ti)的(de)煅燒(shao)(shao)工(gong)(gong)藝(yi)(yi)有(you)半(ban)(ban)干法壓(ya)坯、隧(sui)道(dao)窯(yao)煅燒(shao)(shao)工(gong)(gong)藝(yi)(yi);半(ban)(ban)干法壓(ya)球、焦炭豎窯(yao)煅燒(shao)(shao)工(gong)(gong)藝(yi)(yi);干法壓(ya)球、高溫(wen)(wen)燃油豎窯(yao)和(he)(he)回(hui)轉窯(yao)煅燒(shao)(shao)工(gong)(gong)藝(yi)(yi)。
1、半干法壓坯、隧道窯煅燒(shao)工藝該煅燒(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(gan)法壓球(qiu)、焦炭豎窯煅燒(shao)工藝(yi)
該(gai)煅燒(shao)(shao)(shao)工(gong)(gong)藝(yi)(yi)生(sheng)產(chan)(chan)合(he)(he)成(cheng)(cheng)鎂(mei)鈣砂是以輕(qing)燒(shao)(shao)(shao)白云石(shi)和輕(qing)燒(shao)(shao)(shao)氧化(hua)鎂(mei)為(wei)(wei)原(yuan)料(liao)(liao)。將(jiang)輕(qing)燒(shao)(shao)(shao)白云石(shi)和輕(qing)燒(shao)(shao)(shao)氧化(hua)鎂(mei)分(fen)別(bie)磨成(cheng)(cheng)細粉,計量后(hou)按(an)比例(li)加(jia)入(ru)(ru)(ru)輪碾(nian)機中再加(jia)水混(hun)(hun)合(he)(he),混(hun)(hun)好的(de)合(he)(he)成(cheng)(cheng)料(liao)(liao)在(zai)雙(shuang)輥(gun)壓(ya)球(qiu)(qiu)機上壓(ya)成(cheng)(cheng)料(liao)(liao)球(qiu)(qiu),干燥后(hou)裝(zhuang)入(ru)(ru)(ru)以焦(jiao)炭或(huo)無煙(yan)煤(mei)為(wei)(wei)燃料(liao)(liao)的(de)豎(shu)窯(yao)內煅燒(shao)(shao)(shao)。裝(zhuang)料(liao)(liao)方(fang)式(shi)是焦(jiao)炭或(huo)無煙(yan)煤(mei)和料(liao)(liao)球(qiu)(qiu)分(fen)層裝(zhuang)入(ru)(ru)(ru)。我(wo)國遼寧省生(sheng)產(chan)(chan)合(he)(he)成(cheng)(cheng)鎂(mei)鈣砂的(de)企業中,大部分(fen)采用該(gai)煅燒(shao)(shao)(shao)工(gong)(gong)藝(yi)(yi)。所(suo)用豎(shu)窯(yao)的(de)規(gui)格一(yi)般為(wei)(wei)3m×16m。該(gai)煅燒(shao)(shao)(shao)工(gong)(gong)藝(yi)(yi)簡(jian)單,產(chan)(chan)品成(cheng)(cheng)本低,但在(zai)煅燒(shao)(shao)(shao)過程中料(liao)(liao)球(qiu)(qiu)和焦(jiao)炭混(hun)(hun)在(zai)一(yi)起,焦(jiao)炭燃燒(shao)(shao)(shao)產(chan)(chan)生(sheng)的(de)灰分(fen)有一(yi)部分(fen)混(hun)(hun)入(ru)(ru)(ru)到(dao)料(liao)(liao)球(qiu)(qiu)中,增加(jia)了產(chan)(chan)品的(de)雜(za)質(zhi)含量。
3、干法壓球(qiu)、燃油豎窯(yao)煅燒工(gong)藝
該(gai)煅(duan)燒(shao)(shao)(shao)(shao)工(gong)藝(yi)用于(yu)生(sheng)產(chan)(chan)高(gao)純度(du)(du)(du)合成(cheng)鎂(mei)(mei)鈣砂。將(jiang)高(gao)純度(du)(du)(du)輕(qing)燒(shao)(shao)(shao)(shao)氧化(hua)鎂(mei)(mei)和(he)輕(qing)燒(shao)(shao)(shao)(shao)白云石配料(liao)(liao)、混合磨(mo)細后,直接將(jiang)干(gan)粉料(liao)(liao)送入高(gao)壓(ya)(ya)壓(ya)(ya)球機中干(gan)壓(ya)(ya)成(cheng)球,然后再(zai)送入高(gao)溫(wen)燃(ran)油豎窯(yao)(yao)(yao)內(nei)煅(duan)燒(shao)(shao)(shao)(shao)。這種(zhong)煅(duan)燒(shao)(shao)(shao)(shao)工(gong)藝(yi)的(de)(de)(de)優(you)勢是燃(ran)料(liao)(liao)油噴入到料(liao)(liao)層內(nei),在料(liao)(liao)層內(nei)部燃(ran)燒(shao)(shao)(shao)(shao),煅(duan)燒(shao)(shao)(shao)(shao)溫(wen)度(du)(du)(du)高(gao),可達到1800℃以上;燃(ran)料(liao)(liao)燃(ran)燒(shao)(shao)(shao)(shao)后不(bu)產(chan)(chan)生(sheng)灰分,對物料(liao)(liao)的(de)(de)(de)純度(du)(du)(du)沒有影(ying)響。目前,國內(nei)采用該(gai)煅(duan)燒(shao)(shao)(shao)(shao)工(gong)藝(yi)生(sheng)產(chan)(chan)合成(cheng)鎂(mei)(mei)鈣砂的(de)(de)(de)企業,只有南方(fang)一(yi)家公(gong)司(si)。該(gai)公(gong)司(si)燃(ran)油豎窯(yao)(yao)(yao)的(de)(de)(de)規格為(wei)φ1.75m×11.5m,窯(yao)(yao)(yao)的(de)(de)(de)工(gong)作襯用高(gao)純度(du)(du)(du)堿性(xing)耐火制品砌筑,厚度(du)(du)(du)為(wei)350mm。工(gong)作襯于(yu)窯(yao)(yao)(yao)體鋼(gang)殼之間(jian)(jian)用輕(qing)質保(bao)溫(wen)磚砌筑。以重柴(chai)油為(wei)燃(ran)料(liao)(liao),煅(duan)燒(shao)(shao)(shao)(shao)溫(wen)度(du)(du)(du)>1800℃。設計(ji)4排燒(shao)(shao)(shao)(shao)嘴(zui),上下布置(zhi),間(jian)(jian)距900mm。每排設計(ji)16支燒(shao)(shao)(shao)(shao)嘴(zui),沿圓周均布。采用無冷卻(que)燒(shao)(shao)(shao)(shao)嘴(zui),每支燒(shao)(shao)(shao)(shao)嘴(zui)配一(yi)臺計(ji)量泵供(gong)油,一(yi)次空(kong)氣由羅茨風機供(gong)應。實際生(sheng)產(chan)(chan)中使用一(yi)排燒(shao)(shao)(shao)(shao)嘴(zui)。連續(xu)裝窯(yao)(yao)(yao)和(he)出窯(yao)(yao)(yao),全部自動化(hua)控制,生(sheng)產(chan)(chan)能力。
4、干法壓球、回轉窯(yao)煅(duan)燒工(gong)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。