和平合成鎂鈣砂的煅燒工藝和煅燒設備
發布日期:2022-01-21 瀏覽(lan)次數(shu):34754目前我國生產和平合成鎂鈣砂所(suo)使用的(de)(de)原料(liao)有(you)菱鎂(mei)(mei)石(shi)(shi)(shi)、白云石(shi)(shi)(shi)和(he)石(shi)(shi)(shi)灰(hui)(hui)石(shi)(shi)(shi)。所(suo)采用的(de)(de)工(gong)(gong)藝(yi)為(wei)二步煅(duan)(duan)燒(shao)(shao)(shao)(shao)、入工(gong)(gong)合成(cheng)工(gong)(gong)藝(yi)。即先將菱鎂(mei)(mei)石(shi)(shi)(shi)、白云石(shi)(shi)(shi)和(he)石(shi)(shi)(shi)灰(hui)(hui)石(shi)(shi)(shi)在較低的(de)(de)溫(wen)度下輕燒(shao)(shao)(shao)(shao),生產出輕燒(shao)(shao)(shao)(shao)氧化鎂(mei)(mei)、輕燒(shao)(shao)(shao)(shao)白云石(shi)(shi)(shi)和(he)生石(shi)(shi)(shi)灰(hui)(hui)。然后(hou)進行(xing)配料(liao)、磨細、混料(liao)、成(cheng)型,最后(hou)經過高溫(wen)煅(duan)(duan)燒(shao)(shao)(shao)(shao),煅(duan)(duan)燒(shao)(shao)(shao)(shao)出不同牌號的(de)(de)合成(cheng)鎂(mei)(mei)鈣砂。具(ju)體的(de)(de)煅(duan)(duan)燒(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)有(you)半(ban)干法(fa)壓(ya)(ya)坯、隧道(dao)窯煅(duan)(duan)燒(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi);半(ban)干法(fa)壓(ya)(ya)球(qiu)、焦炭豎窯煅(duan)(duan)燒(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi);干法(fa)壓(ya)(ya)球(qiu)、高溫(wen)燃油(you)豎窯和(he)回轉窯煅(duan)(duan)燒(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)。
1、半干法壓坯、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、焦炭(tan)豎窯煅燒工藝
該(gai)煅(duan)燒(shao)(shao)工(gong)藝生產合成(cheng)(cheng)鎂(mei)鈣砂是以(yi)輕(qing)燒(shao)(shao)白云(yun)石和(he)(he)輕(qing)燒(shao)(shao)氧化鎂(mei)為(wei)(wei)(wei)原料(liao)(liao)(liao)。將輕(qing)燒(shao)(shao)白云(yun)石和(he)(he)輕(qing)燒(shao)(shao)氧化鎂(mei)分別磨成(cheng)(cheng)細粉,計量后(hou)按比例加入(ru)輪碾機中再加水(shui)混(hun)合,混(hun)好的(de)合成(cheng)(cheng)料(liao)(liao)(liao)在雙輥壓球(qiu)機上壓成(cheng)(cheng)料(liao)(liao)(liao)球(qiu),干(gan)燥后(hou)裝(zhuang)(zhuang)(zhuang)入(ru)以(yi)焦炭或無(wu)煙煤(mei)為(wei)(wei)(wei)燃(ran)料(liao)(liao)(liao)的(de)豎窯內(nei)煅(duan)燒(shao)(shao)。裝(zhuang)(zhuang)(zhuang)料(liao)(liao)(liao)方式是焦炭或無(wu)煙煤(mei)和(he)(he)料(liao)(liao)(liao)球(qiu)分層裝(zhuang)(zhuang)(zhuang)入(ru)。我國遼寧省生產合成(cheng)(cheng)鎂(mei)鈣砂的(de)企(qi)業中,大(da)部(bu)分采用該(gai)煅(duan)燒(shao)(shao)工(gong)藝。所用豎窯的(de)規格一(yi)般(ban)為(wei)(wei)(wei)3m×16m。該(gai)煅(duan)燒(shao)(shao)工(gong)藝簡(jian)單,產品(pin)成(cheng)(cheng)本低(di),但(dan)在煅(duan)燒(shao)(shao)過程中料(liao)(liao)(liao)球(qiu)和(he)(he)焦炭混(hun)在一(yi)起,焦炭燃(ran)燒(shao)(shao)產生的(de)灰(hui)分有一(yi)部(bu)分混(hun)入(ru)到料(liao)(liao)(liao)球(qiu)中,增加了產品(pin)的(de)雜質含(han)量。
3、干法(fa)壓球(qiu)、燃油豎(shu)窯煅燒工藝
該(gai)(gai)煅(duan)(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝用(yong)(yong)于生(sheng)(sheng)(sheng)產(chan)(chan)高純度合成鎂(mei)鈣砂(sha)。將高純度輕(qing)燒(shao)(shao)(shao)氧化鎂(mei)和輕(qing)燒(shao)(shao)(shao)白云(yun)石配(pei)料(liao)(liao)(liao)、混合磨細后,直(zhi)接將干(gan)粉(fen)料(liao)(liao)(liao)送(song)入(ru)高壓(ya)壓(ya)球(qiu)機(ji)中(zhong)干(gan)壓(ya)成球(qiu),然后再送(song)入(ru)高溫(wen)燃(ran)油豎(shu)窯(yao)內煅(duan)(duan)燒(shao)(shao)(shao)。這種煅(duan)(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝的(de)(de)(de)(de)優勢是燃(ran)料(liao)(liao)(liao)油噴入(ru)到料(liao)(liao)(liao)層內,在料(liao)(liao)(liao)層內部(bu)燃(ran)燒(shao)(shao)(shao),煅(duan)(duan)燒(shao)(shao)(shao)溫(wen)度高,可達到1800℃以(yi)(yi)上(shang);燃(ran)料(liao)(liao)(liao)燃(ran)燒(shao)(shao)(shao)后不產(chan)(chan)生(sheng)(sheng)(sheng)灰分,對物料(liao)(liao)(liao)的(de)(de)(de)(de)純度沒有影響。目前,國內采(cai)用(yong)(yong)該(gai)(gai)煅(duan)(duan)燒(shao)(shao)(shao)工(gong)(gong)(gong)藝生(sheng)(sheng)(sheng)產(chan)(chan)合成鎂(mei)鈣砂(sha)的(de)(de)(de)(de)企業,只有南方(fang)一(yi)家公司。該(gai)(gai)公司燃(ran)油豎(shu)窯(yao)的(de)(de)(de)(de)規格(ge)為(wei)(wei)(wei)φ1.75m×11.5m,窯(yao)的(de)(de)(de)(de)工(gong)(gong)(gong)作襯用(yong)(yong)高純度堿性(xing)耐火制(zhi)(zhi)品砌筑,厚(hou)度為(wei)(wei)(wei)350mm。工(gong)(gong)(gong)作襯于窯(yao)體鋼殼之間用(yong)(yong)輕(qing)質保溫(wen)磚砌筑。以(yi)(yi)重(zhong)柴油為(wei)(wei)(wei)燃(ran)料(liao)(liao)(liao),煅(duan)(duan)燒(shao)(shao)(shao)溫(wen)度>1800℃。設計4排(pai)(pai)燒(shao)(shao)(shao)嘴,上(shang)下布置,間距(ju)900mm。每排(pai)(pai)設計16支燒(shao)(shao)(shao)嘴,沿圓周(zhou)均布。采(cai)用(yong)(yong)無冷卻燒(shao)(shao)(shao)嘴,每支燒(shao)(shao)(shao)嘴配(pei)一(yi)臺計量(liang)泵供油,一(yi)次空氣由羅茨(ci)風機(ji)供應。實(shi)際生(sheng)(sheng)(sheng)產(chan)(chan)中(zhong)使用(yong)(yong)一(yi)排(pai)(pai)燒(shao)(shao)(shao)嘴。連(lian)續裝窯(yao)和出(chu)窯(yao),全部(bu)自動化控制(zhi)(zhi),生(sheng)(sheng)(sheng)產(chan)(chan)能力(li)。
4、干法(fa)壓球、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。