泰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(ci)數:34682目前我國生產泰州合成鎂鈣砂所(suo)使用(yong)的(de)(de)原料有(you)菱鎂(mei)石(shi)(shi)(shi)、白云石(shi)(shi)(shi)和石(shi)(shi)(shi)灰石(shi)(shi)(shi)。所(suo)采(cai)用(yong)的(de)(de)工(gong)(gong)(gong)藝(yi)為二步煅燒(shao)(shao)(shao)、入工(gong)(gong)(gong)合成工(gong)(gong)(gong)藝(yi)。即先將菱鎂(mei)石(shi)(shi)(shi)、白云石(shi)(shi)(shi)和石(shi)(shi)(shi)灰石(shi)(shi)(shi)在較低(di)的(de)(de)溫(wen)度下輕(qing)燒(shao)(shao)(shao),生(sheng)產出(chu)輕(qing)燒(shao)(shao)(shao)氧(yang)化鎂(mei)、輕(qing)燒(shao)(shao)(shao)白云石(shi)(shi)(shi)和生(sheng)石(shi)(shi)(shi)灰。然后進行配料、磨細、混料、成型,最后經過高溫(wen)煅燒(shao)(shao)(shao),煅燒(shao)(shao)(shao)出(chu)不同牌號的(de)(de)合成鎂(mei)鈣砂。具(ju)體的(de)(de)煅燒(shao)(shao)(shao)工(gong)(gong)(gong)藝(yi)有(you)半干法(fa)壓坯、隧道(dao)窯(yao)煅燒(shao)(shao)(shao)工(gong)(gong)(gong)藝(yi);半干法(fa)壓球、焦炭豎(shu)窯(yao)煅燒(shao)(shao)(shao)工(gong)(gong)(gong)藝(yi);干法(fa)壓球、高溫(wen)燃(ran)油豎(shu)窯(yao)和回轉窯(yao)煅燒(shao)(shao)(shao)工(gong)(gong)(gong)藝(yi)。
1、半干(gan)法壓坯、隧道窯(yao)煅燒(shao)(shao)工藝(yi)(yi)該煅燒(shao)(shao)工藝(yi)(yi)
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(ya)球(qiu)、焦炭豎(shu)窯煅燒工(gong)藝
該煅(duan)(duan)燒(shao)(shao)(shao)工(gong)藝生(sheng)產(chan)合(he)(he)成(cheng)鎂(mei)鈣砂(sha)是以(yi)輕(qing)燒(shao)(shao)(shao)白云(yun)石(shi)和輕(qing)燒(shao)(shao)(shao)氧化鎂(mei)為原(yuan)料(liao)(liao)(liao)(liao)。將輕(qing)燒(shao)(shao)(shao)白云(yun)石(shi)和輕(qing)燒(shao)(shao)(shao)氧化鎂(mei)分別磨成(cheng)細粉,計量(liang)后按比例加入(ru)輪碾機中(zhong)(zhong)再加水混(hun)合(he)(he),混(hun)好的(de)(de)合(he)(he)成(cheng)料(liao)(liao)(liao)(liao)在(zai)雙(shuang)輥(gun)壓球(qiu)(qiu)(qiu)機上壓成(cheng)料(liao)(liao)(liao)(liao)球(qiu)(qiu)(qiu),干燥(zao)后裝入(ru)以(yi)焦(jiao)炭或無煙煤(mei)為燃(ran)料(liao)(liao)(liao)(liao)的(de)(de)豎窯內煅(duan)(duan)燒(shao)(shao)(shao)。裝料(liao)(liao)(liao)(liao)方式是焦(jiao)炭或無煙煤(mei)和料(liao)(liao)(liao)(liao)球(qiu)(qiu)(qiu)分層(ceng)裝入(ru)。我國(guo)遼寧省生(sheng)產(chan)合(he)(he)成(cheng)鎂(mei)鈣砂(sha)的(de)(de)企業(ye)中(zhong)(zhong),大部分采(cai)用該煅(duan)(duan)燒(shao)(shao)(shao)工(gong)藝。所(suo)用豎窯的(de)(de)規格(ge)一般(ban)為3m×16m。該煅(duan)(duan)燒(shao)(shao)(shao)工(gong)藝簡單,產(chan)品(pin)成(cheng)本低(di),但在(zai)煅(duan)(duan)燒(shao)(shao)(shao)過(guo)程(cheng)中(zhong)(zhong)料(liao)(liao)(liao)(liao)球(qiu)(qiu)(qiu)和焦(jiao)炭混(hun)在(zai)一起,焦(jiao)炭燃(ran)燒(shao)(shao)(shao)產(chan)生(sheng)的(de)(de)灰分有一部分混(hun)入(ru)到(dao)料(liao)(liao)(liao)(liao)球(qiu)(qiu)(qiu)中(zhong)(zhong),增加了產(chan)品(pin)的(de)(de)雜(za)質含量(liang)。
3、干法壓球、燃油(you)豎窯煅(duan)燒工藝
該煅(duan)(duan)(duan)燒(shao)(shao)工藝用(yong)于生(sheng)產(chan)高(gao)純度(du)合(he)成(cheng)鎂(mei)(mei)鈣砂(sha)。將高(gao)純度(du)輕燒(shao)(shao)氧化鎂(mei)(mei)和輕燒(shao)(shao)白云石配料(liao)、混(hun)合(he)磨細(xi)后(hou),直接將干(gan)粉料(liao)送入(ru)高(gao)壓壓球機中干(gan)壓成(cheng)球,然后(hou)再送入(ru)高(gao)溫燃(ran)(ran)油豎(shu)窯(yao)內(nei)煅(duan)(duan)(duan)燒(shao)(shao)。這(zhe)種煅(duan)(duan)(duan)燒(shao)(shao)工藝的(de)(de)優勢是燃(ran)(ran)料(liao)油噴(pen)入(ru)到料(liao)層(ceng)內(nei),在料(liao)層(ceng)內(nei)部燃(ran)(ran)燒(shao)(shao),煅(duan)(duan)(duan)燒(shao)(shao)溫度(du)高(gao),可(ke)達到1800℃以(yi)上(shang);燃(ran)(ran)料(liao)燃(ran)(ran)燒(shao)(shao)后(hou)不產(chan)生(sheng)灰(hui)分,對(dui)物料(liao)的(de)(de)純度(du)沒有影響。目前,國(guo)內(nei)采用(yong)該煅(duan)(duan)(duan)燒(shao)(shao)工藝生(sheng)產(chan)合(he)成(cheng)鎂(mei)(mei)鈣砂(sha)的(de)(de)企(qi)業,只有南方一家公司。該公司燃(ran)(ran)油豎(shu)窯(yao)的(de)(de)規(gui)格(ge)為φ1.75m×11.5m,窯(yao)的(de)(de)工作襯用(yong)高(gao)純度(du)堿性(xing)耐火(huo)制品砌(qi)筑,厚(hou)度(du)為350mm。工作襯于窯(yao)體鋼(gang)殼(ke)之間用(yong)輕質(zhi)保溫磚砌(qi)筑。以(yi)重柴油為燃(ran)(ran)料(liao),煅(duan)(duan)(duan)燒(shao)(shao)溫度(du)>1800℃。設(she)計4排燒(shao)(shao)嘴,上(shang)下布(bu)置,間距(ju)900mm。每排設(she)計16支(zhi)燒(shao)(shao)嘴,沿圓(yuan)周(zhou)均布(bu)。采用(yong)無冷卻燒(shao)(shao)嘴,每支(zhi)燒(shao)(shao)嘴配一臺(tai)計量泵供油,一次空(kong)氣由羅茨(ci)風機供應。實際生(sheng)產(chan)中使(shi)用(yong)一排燒(shao)(shao)嘴。連續裝窯(yao)和出窯(yao),全(quan)部自動(dong)化控制,生(sheng)產(chan)能(neng)力。
4、干法(fa)壓(ya)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。