濟寧合成鎂鈣砂的煅燒工藝和煅燒設備
發(fa)布日期:2022-01-21 瀏覽(lan)次數:34868目前我國生產濟寧合成鎂鈣砂所使用(yong)的(de)原料(liao)有(you)菱鎂(mei)石(shi)(shi)(shi)(shi)、白云石(shi)(shi)(shi)(shi)和石(shi)(shi)(shi)(shi)灰石(shi)(shi)(shi)(shi)。所采用(yong)的(de)工(gong)藝(yi)(yi)為二步(bu)煅燒(shao)(shao)(shao)、入工(gong)合(he)成(cheng)工(gong)藝(yi)(yi)。即先(xian)將菱鎂(mei)石(shi)(shi)(shi)(shi)、白云石(shi)(shi)(shi)(shi)和石(shi)(shi)(shi)(shi)灰石(shi)(shi)(shi)(shi)在(zai)較低的(de)溫(wen)(wen)度下輕(qing)燒(shao)(shao)(shao),生(sheng)產出(chu)(chu)輕(qing)燒(shao)(shao)(shao)氧化鎂(mei)、輕(qing)燒(shao)(shao)(shao)白云石(shi)(shi)(shi)(shi)和生(sheng)石(shi)(shi)(shi)(shi)灰。然后(hou)進行配料(liao)、磨細、混(hun)料(liao)、成(cheng)型(xing),最后(hou)經過(guo)高(gao)溫(wen)(wen)煅燒(shao)(shao)(shao),煅燒(shao)(shao)(shao)出(chu)(chu)不同牌(pai)號的(de)合(he)成(cheng)鎂(mei)鈣砂。具體的(de)煅燒(shao)(shao)(shao)工(gong)藝(yi)(yi)有(you)半干(gan)法(fa)壓坯、隧道窯煅燒(shao)(shao)(shao)工(gong)藝(yi)(yi);半干(gan)法(fa)壓球(qiu)、焦炭豎(shu)窯煅燒(shao)(shao)(shao)工(gong)藝(yi)(yi);干(gan)法(fa)壓球(qiu)、高(gao)溫(wen)(wen)燃油豎(shu)窯和回轉(zhuan)窯煅燒(shao)(shao)(shao)工(gong)藝(yi)(yi)。
1、半干法(fa)壓坯(pi)、隧道(dao)窯煅(duan)燒(shao)(shao)工(gong)藝(yi)該煅(duan)燒(shao)(shao)工(gong)藝(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(gan)法壓球(qiu)、焦炭豎窯煅燒工(gong)藝
該煅(duan)燒(shao)(shao)工(gong)藝生(sheng)(sheng)產合成(cheng)(cheng)鎂(mei)(mei)鈣砂是以輕(qing)燒(shao)(shao)白云(yun)石(shi)和輕(qing)燒(shao)(shao)氧(yang)(yang)化鎂(mei)(mei)為(wei)原料(liao)(liao)。將輕(qing)燒(shao)(shao)白云(yun)石(shi)和輕(qing)燒(shao)(shao)氧(yang)(yang)化鎂(mei)(mei)分(fen)別磨(mo)成(cheng)(cheng)細(xi)粉,計量后按(an)比(bi)例加(jia)入(ru)輪碾機中(zhong)(zhong)再加(jia)水(shui)混(hun)合,混(hun)好(hao)的(de)(de)合成(cheng)(cheng)料(liao)(liao)在(zai)雙(shuang)輥壓球(qiu)(qiu)機上壓成(cheng)(cheng)料(liao)(liao)球(qiu)(qiu),干燥后裝入(ru)以焦(jiao)炭(tan)或無煙煤為(wei)燃(ran)料(liao)(liao)的(de)(de)豎(shu)窯內煅(duan)燒(shao)(shao)。裝料(liao)(liao)方式是焦(jiao)炭(tan)或無煙煤和料(liao)(liao)球(qiu)(qiu)分(fen)層裝入(ru)。我(wo)國遼寧省生(sheng)(sheng)產合成(cheng)(cheng)鎂(mei)(mei)鈣砂的(de)(de)企業中(zhong)(zhong),大(da)部分(fen)采用(yong)該煅(duan)燒(shao)(shao)工(gong)藝。所(suo)用(yong)豎(shu)窯的(de)(de)規格一般(ban)為(wei)3m×16m。該煅(duan)燒(shao)(shao)工(gong)藝簡單,產品(pin)成(cheng)(cheng)本低(di),但在(zai)煅(duan)燒(shao)(shao)過程中(zhong)(zhong)料(liao)(liao)球(qiu)(qiu)和焦(jiao)炭(tan)混(hun)在(zai)一起,焦(jiao)炭(tan)燃(ran)燒(shao)(shao)產生(sheng)(sheng)的(de)(de)灰分(fen)有一部分(fen)混(hun)入(ru)到料(liao)(liao)球(qiu)(qiu)中(zhong)(zhong),增(zeng)加(jia)了產品(pin)的(de)(de)雜質(zhi)含(han)量。
3、干法壓球(qiu)、燃油豎(shu)窯(yao)煅燒工藝
該煅(duan)燒(shao)(shao)(shao)(shao)工藝用(yong)于生產(chan)高(gao)純(chun)度(du)(du)合(he)成(cheng)(cheng)鎂鈣砂(sha)。將高(gao)純(chun)度(du)(du)輕燒(shao)(shao)(shao)(shao)氧化(hua)鎂和輕燒(shao)(shao)(shao)(shao)白云石配料(liao)(liao)、混合(he)磨細后,直接將干(gan)粉料(liao)(liao)送入(ru)高(gao)壓壓球(qiu)機中干(gan)壓成(cheng)(cheng)球(qiu),然后再(zai)送入(ru)高(gao)溫(wen)燃油(you)豎窯(yao)內煅(duan)燒(shao)(shao)(shao)(shao)。這種煅(duan)燒(shao)(shao)(shao)(shao)工藝的(de)優勢是燃料(liao)(liao)油(you)噴入(ru)到料(liao)(liao)層內,在料(liao)(liao)層內部燃燒(shao)(shao)(shao)(shao),煅(duan)燒(shao)(shao)(shao)(shao)溫(wen)度(du)(du)高(gao),可達(da)到1800℃以(yi)上;燃料(liao)(liao)燃燒(shao)(shao)(shao)(shao)后不(bu)產(chan)生灰分,對物(wu)料(liao)(liao)的(de)純(chun)度(du)(du)沒有影響。目(mu)前,國內采用(yong)該煅(duan)燒(shao)(shao)(shao)(shao)工藝生產(chan)合(he)成(cheng)(cheng)鎂鈣砂(sha)的(de)企業,只有南方(fang)一(yi)(yi)家公(gong)司。該公(gong)司燃油(you)豎窯(yao)的(de)規格為(wei)φ1.75m×11.5m,窯(yao)的(de)工作襯(chen)(chen)用(yong)高(gao)純(chun)度(du)(du)堿(jian)性耐火制品砌筑,厚度(du)(du)為(wei)350mm。工作襯(chen)(chen)于窯(yao)體鋼殼之間(jian)用(yong)輕質保溫(wen)磚砌筑。以(yi)重(zhong)柴油(you)為(wei)燃料(liao)(liao),煅(duan)燒(shao)(shao)(shao)(shao)溫(wen)度(du)(du)>1800℃。設計4排燒(shao)(shao)(shao)(shao)嘴,上下布置(zhi),間(jian)距900mm。每(mei)排設計16支(zhi)燒(shao)(shao)(shao)(shao)嘴,沿圓周(zhou)均布。采用(yong)無冷卻燒(shao)(shao)(shao)(shao)嘴,每(mei)支(zhi)燒(shao)(shao)(shao)(shao)嘴配一(yi)(yi)臺計量泵供油(you),一(yi)(yi)次空氣由羅茨風機供應。實(shi)際生產(chan)中使用(yong)一(yi)(yi)排燒(shao)(shao)(shao)(shao)嘴。連(lian)續裝窯(yao)和出窯(yao),全部自動化(hua)控制,生產(chan)能(neng)力。
4、干法壓球、回轉(zhuan)窯煅燒(shao)工(gong)藝(yi)
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。