目前我國生產錦州合成鎂鈣砂所(suo)使用(yong)(yong)的原料有(you)菱(ling)鎂石(shi)(shi)、白云石(shi)(shi)和(he)石(shi)(shi)灰石(shi)(shi)。所(suo)采用(yong)(yong)的工(gong)(gong)(gong)(gong)(gong)藝為(wei)二步煅(duan)(duan)燒(shao)(shao)、入工(gong)(gong)(gong)(gong)(gong)合成工(gong)(gong)(gong)(gong)(gong)藝。即先將(jiang)菱(ling)鎂石(shi)(shi)、白云石(shi)(shi)和(he)石(shi)(shi)灰石(shi)(shi)在較低的溫度下輕(qing)燒(shao)(shao)，生產(chan)出(chu)輕(qing)燒(shao)(shao)氧化鎂、輕(qing)燒(shao)(shao)白云石(shi)(shi)和(he)生石(shi)(shi)灰。然后進(jin)行配料、磨細、混料、成型，最后經過高(gao)溫煅(duan)(duan)燒(shao)(shao)，煅(duan)(duan)燒(shao)(shao)出(chu)不同(tong)牌號的合成鎂鈣(gai)砂。具體的煅(duan)(duan)燒(shao)(shao)工(gong)(gong)(gong)(gong)(gong)藝有(you)半(ban)干(gan)法(fa)壓坯(pi)、隧道窯(yao)煅(duan)(duan)燒(shao)(shao)工(gong)(gong)(gong)(gong)(gong)藝；半(ban)干(gan)法(fa)壓球、焦(jiao)炭豎(shu)窯(yao)煅(duan)(duan)燒(shao)(shao)工(gong)(gong)(gong)(gong)(gong)藝；干(gan)法(fa)壓球、高(gao)溫燃油豎(shu)窯(yao)和(he)回轉(zhuan)窯(yao)煅(duan)(duan)燒(shao)(shao)工(gong)(gong)(gong)(gong)(gong)藝。

1、半干法壓坯、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、半干法壓球(qiu)、焦炭(tan)豎(shu)窯煅燒工藝

該(gai)(gai)煅燒(shao)工(gong)藝(yi)生產合(he)成(cheng)鎂(mei)鈣砂是(shi)以(yi)輕(qing)燒(shao)白云石(shi)和(he)輕(qing)燒(shao)氧化(hua)鎂(mei)為原料。將輕(qing)燒(shao)白云石(shi)和(he)輕(qing)燒(shao)氧化(hua)鎂(mei)分別磨成(cheng)細(xi)粉，計(ji)量后按比例(li)加入輪(lun)碾機中(zhong)再加水混(hun)(hun)合(he)，混(hun)(hun)好的(de)合(he)成(cheng)料在(zai)(zai)雙輥壓(ya)(ya)球機上壓(ya)(ya)成(cheng)料球，干燥后裝入以(yi)焦(jiao)炭(tan)或無煙煤為燃料的(de)豎窯(yao)內煅燒(shao)。裝料方式是(shi)焦(jiao)炭(tan)或無煙煤和(he)料球分層裝入。我國遼寧(ning)省(sheng)生產合(he)成(cheng)鎂(mei)鈣砂的(de)企業中(zhong)，大(da)部分采用該(gai)(gai)煅燒(shao)工(gong)藝(yi)。所用豎窯(yao)的(de)規格一般為3m×16m。該(gai)(gai)煅燒(shao)工(gong)藝(yi)簡單，產品(pin)成(cheng)本低，但(dan)在(zai)(zai)煅燒(shao)過程中(zhong)料球和(he)焦(jiao)炭(tan)混(hun)(hun)在(zai)(zai)一起(qi)，焦(jiao)炭(tan)燃燒(shao)產生的(de)灰分有一部分混(hun)(hun)入到料球中(zhong)，增加了產品(pin)的(de)雜質含量。

3、干法壓(ya)球、燃油豎窯煅燒工藝

該(gai)煅(duan)(duan)(duan)燒(shao)(shao)(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)用(yong)(yong)于生(sheng)(sheng)(sheng)產(chan)(chan)高(gao)(gao)(gao)(gao)純度(du)(du)合(he)成鎂鈣砂(sha)。將(jiang)高(gao)(gao)(gao)(gao)純度(du)(du)輕(qing)燒(shao)(shao)(shao)(shao)(shao)(shao)氧化(hua)鎂和輕(qing)燒(shao)(shao)(shao)(shao)(shao)(shao)白云石(shi)配料、混合(he)磨細后(hou)，直接(jie)將(jiang)干粉料送入(ru)高(gao)(gao)(gao)(gao)壓壓球機中(zhong)干壓成球，然(ran)后(hou)再送入(ru)高(gao)(gao)(gao)(gao)溫燃(ran)(ran)油豎(shu)(shu)窯(yao)內(nei)煅(duan)(duan)(duan)燒(shao)(shao)(shao)(shao)(shao)(shao)。這種煅(duan)(duan)(duan)燒(shao)(shao)(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)的(de)優勢是燃(ran)(ran)料油噴入(ru)到料層內(nei)，在料層內(nei)部(bu)燃(ran)(ran)燒(shao)(shao)(shao)(shao)(shao)(shao)，煅(duan)(duan)(duan)燒(shao)(shao)(shao)(shao)(shao)(shao)溫度(du)(du)高(gao)(gao)(gao)(gao)，可(ke)達到1800℃以(yi)(yi)上；燃(ran)(ran)料燃(ran)(ran)燒(shao)(shao)(shao)(shao)(shao)(shao)后(hou)不產(chan)(chan)生(sheng)(sheng)(sheng)灰分，對物料的(de)純度(du)(du)沒有影響。目前(qian)，國內(nei)采用(yong)(yong)該(gai)煅(duan)(duan)(duan)燒(shao)(shao)(shao)(shao)(shao)(shao)工(gong)(gong)藝(yi)生(sheng)(sheng)(sheng)產(chan)(chan)合(he)成鎂鈣砂(sha)的(de)企業，只有南方一(yi)家公司(si)。該(gai)公司(si)燃(ran)(ran)油豎(shu)(shu)窯(yao)的(de)規格(ge)為φ1.75m×11.5m，窯(yao)的(de)工(gong)(gong)作襯(chen)用(yong)(yong)高(gao)(gao)(gao)(gao)純度(du)(du)堿(jian)性耐火制品砌筑，厚(hou)度(du)(du)為350mm。工(gong)(gong)作襯(chen)于窯(yao)體鋼(gang)殼之(zhi)間用(yong)(yong)輕(qing)質保溫磚砌筑。以(yi)(yi)重柴油為燃(ran)(ran)料，煅(duan)(duan)(duan)燒(shao)(shao)(shao)(shao)(shao)(shao)溫度(du)(du)>1800℃。設(she)計4排(pai)燒(shao)(shao)(shao)(shao)(shao)(shao)嘴，上下(xia)布置，間距900mm。每排(pai)設(she)計16支(zhi)燒(shao)(shao)(shao)(shao)(shao)(shao)嘴，沿圓周均(jun)布。采用(yong)(yong)無冷卻(que)燒(shao)(shao)(shao)(shao)(shao)(shao)嘴，每支(zhi)燒(shao)(shao)(shao)(shao)(shao)(shao)嘴配一(yi)臺計量(liang)泵供油，一(yi)次空氣由羅(luo)茨風機供應。實際生(sheng)(sheng)(sheng)產(chan)(chan)中(zhong)使用(yong)(yong)一(yi)排(pai)燒(shao)(shao)(shao)(shao)(shao)(shao)嘴。連(lian)續裝窯(yao)和出窯(yao)，全(quan)部(bu)自動化(hua)控制，生(sheng)(sheng)(sheng)產(chan)(chan)能力。

4、干法壓球、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。