銅礦石如何提煉銅

從銅礦中開采出來的銅礦石，經(jing)過選礦(kuang)成為含銅(tong)品位(wei)較(jiao)高的銅(tong)精礦(kuang)或者說是銅(tong)礦(kuang)砂，銅(tong)精礦(kuang)需(xu)要經(jing)過冶煉提成，才能成為精銅(tong)及銅(tong)制品。最早的銅(tong)礦(kuang)石來源是孔雀石。

1、礦石的加工

銅礦石的(de)分類及屬性：

煉(lian)銅(tong)(tong)的原料(liao)是銅(tong)(tong)礦(kuang)石(shi)。銅(tong)(tong)礦(kuang)石(shi)可分(fen)為三類：

（1）硫化礦(kuang)(kuang)，如黃銅(tong)礦(kuang)(kuang)（CuFeS2）、斑銅(tong)礦(kuang)(kuang)（Cu5FeS4）和(he)輝銅(tong)礦(kuang)(kuang)（Cu2S）等。

（2）氧(yang)化(hua)礦(kuang)，如赤銅礦(kuang)（Cu2O）、孔(kong)雀石[Cu?(OH)?CO?]、藍銅礦(kuang)[2CuCO3·Cu(OH)2]、硅(gui)孔(kong)雀石（CuSiO3·2H2O）等。

（3）自然銅(tong)。銅(tong)礦石中銅(tong)的(de)含量(liang)在1%左右（0.5%～3%）的(de)便有(you)開采價值，因為采用浮(fu)選法可以把礦石中一(yi)部分脈石等(deng)雜(za)質除去，而(er)得到含銅(tong)量(liang)較(jiao)高（8%～35%）的(de)精(jing)礦砂。

2、冶煉過程

（1）火法煉銅

通過熔(rong)融冶煉(lian)(lian)和電解(jie)精火煉(lian)(lian)生產出陰極銅(tong)(tong)，也即電解(jie)銅(tong)(tong)，一(yi)般適于高品位的(de)(de)(de)硫(liu)化(hua)(hua)銅(tong)(tong)礦。火法冶煉(lian)(lian)一(yi)般是先將含(han)銅(tong)(tong)百分之幾或千分之幾的(de)(de)(de)原礦石(shi)，通過選礦提(ti)高到(dao)20%～30%，作為銅(tong)(tong)精礦，在密閉鼓風爐(lu)、反射(she)爐(lu)、電爐(lu)或閃速爐(lu)進行造(zao)锍熔(rong)煉(lian)(lian)，產出的(de)(de)(de)熔(rong)锍（冰銅(tong)(tong)）接著(zhu)送入轉爐(lu)進行吹煉(lian)(lian)成(cheng)粗(cu)銅(tong)(tong)，再在另(ling)一(yi)種反射(she)爐(lu)內經過氧化(hua)(hua)精煉(lian)(lian)脫雜，或鑄成(cheng)陽極板(ban)進行電解(jie)，獲得(de)品位高達99.9%的(de)(de)(de)電解(jie)銅(tong)(tong)。該流程簡短、適應性(xing)強(qiang)，銅(tong)(tong)的(de)(de)(de)回收率可達95%，但因礦石(shi)中(zhong)的(de)(de)(de)硫(liu)在造(zao)锍和吹煉(lian)(lian)兩階段作為二氧化(hua)(hua)硫(liu)廢氣排出，不易(yi)回收，易(yi)造(zao)成(cheng)污染(ran)。

從銅礦石冶(ye)煉銅(tong)(tong)(tong)(tong)：以黃(huang)銅(tong)(tong)(tong)(tong)礦為(wei)(wei)例(li)，首先把精礦砂(sha)、熔(rong)劑（石(shi)灰石(shi)、砂(sha)等(deng)）和燃料（焦炭、木炭或(huo)無(wu)煙煤）混合，投入(ru)“密(mi)閉”鼓風(feng)爐(lu)中，在(zai)1000℃左(zuo)右(you)進行熔(rong)煉。于是礦石(shi)中一部(bu)分(fen)硫成(cheng)(cheng)(cheng)為(wei)(wei)SO?（用于制(zhi)硫酸），大部(bu)分(fen)的(de)砷、銻等(deng)雜(za)質(zhi)成(cheng)(cheng)(cheng)為(wei)(wei)As?O?、Sb?O?等(deng)揮發性(xing)物質(zhi)而(er)被除(chu)去：2CuFeS?+O?=Cu?S+2FeS+SO?↑。一部(bu)分(fen)鐵(tie)的(de)硫化(hua)(hua)(hua)(hua)物轉變(bian)為(wei)(wei)氧化(hua)(hua)(hua)(hua)物：2FeS+3O?=2FeO+2SO?↑。Cu?S跟剩(sheng)余的(de)FeS等(deng)便(bian)熔(rong)融在(zai)一起而(er)形成(cheng)(cheng)(cheng)“冰(bing)銅(tong)(tong)(tong)(tong)”（主要由(you)Cu?S和FeS互相溶解形成(cheng)(cheng)(cheng)的(de)，它的(de)含(han)(han)銅(tong)(tong)(tong)(tong)率在(zai)20%～50%之間，含(han)(han)硫率在(zai)23%～27%之間），FeO跟SiO?形成(cheng)(cheng)(cheng)熔(rong)渣(zha)：FeO+SiO?=FeSiO?。熔(rong)渣(zha)浮在(zai)熔(rong)融冰(bing)銅(tong)(tong)(tong)(tong)的(de)上面，容易分(fen)離，借以除(chu)去一部(bu)分(fen)雜(za)質(zhi)。然后(hou)把冰(bing)銅(tong)(tong)(tong)(tong)移(yi)入(ru)轉爐(lu)中，加入(ru)熔(rong)劑（石(shi)英(ying)砂(sha)）后(hou)鼓入(ru)空(kong)(kong)氣(qi)進行吹煉（1100～1300℃）。由(you)于鐵(tie)比(bi)銅(tong)(tong)(tong)(tong)對氧有(you)較大的(de)親(qin)和力，而(er)銅(tong)(tong)(tong)(tong)比(bi)鐵(tie)對硫有(you)較大的(de)親(qin)和力，因(yin)此冰(bing)銅(tong)(tong)(tong)(tong)中的(de)FeS先轉變(bian)為(wei)(wei)FeO，跟熔(rong)劑結(jie)合成(cheng)(cheng)(cheng)渣(zha)，而(er)后(hou)Cu?S才轉變(bian)為(wei)(wei)Cu?O，Cu?O跟Cu?S反應(ying)生成(cheng)(cheng)(cheng)粗(cu)銅(tong)(tong)(tong)(tong)（含(han)(han)銅(tong)(tong)(tong)(tong)量約為(wei)(wei)98.5%）。2Cu?S+3O?=2Cu?O+2SO?↑，2Cu?O+Cu?S=6Cu+SO?↑，再把粗(cu)銅(tong)(tong)(tong)(tong)移(yi)入(ru)反射爐(lu)，加入(ru)熔(rong)劑（石(shi)英(ying)砂(sha)），通入(ru)空(kong)(kong)氣(qi)，使(shi)粗(cu)銅(tong)(tong)(tong)(tong)中的(de)雜(za)質(zhi)氧化(hua)(hua)(hua)(hua)，跟熔(rong)劑形成(cheng)(cheng)(cheng)爐(lu)渣(zha)而(er)除(chu)去。在(zai)雜(za)質(zhi)除(chu)到一定程(cheng)度后(hou)，再噴入(ru)重油(you)，由(you)重油(you)燃燒產生的(de)一氧化(hua)(hua)(hua)(hua)碳等(deng)還(huan)原性(xing)氣(qi)體使(shi)氧化(hua)(hua)(hua)(hua)亞銅(tong)(tong)(tong)(tong)在(zai)高溫下(xia)還(huan)原為(wei)(wei)銅(tong)(tong)(tong)(tong)。得(de)到的(de)精銅(tong)(tong)(tong)(tong)約含(han)(han)銅(tong)(tong)(tong)(tong)99.7%。

除了銅(tong)(tong)(tong)精礦之(zhi)(zhi)外，廢(fei)(fei)(fei)銅(tong)(tong)(tong)作為精煉銅(tong)(tong)(tong)的(de)(de)主要原料(liao)之(zhi)(zhi)一(yi)，包括舊廢(fei)(fei)(fei)銅(tong)(tong)(tong)和(he)(he)新(xin)廢(fei)(fei)(fei)銅(tong)(tong)(tong)，舊廢(fei)(fei)(fei)銅(tong)(tong)(tong)來自舊設備和(he)(he)舊機(ji)器，廢(fei)(fei)(fei)棄(qi)(qi)的(de)(de)樓房(fang)和(he)(he)地(di)下(xia)管(guan)道；新(xin)廢(fei)(fei)(fei)銅(tong)(tong)(tong)來自加工廠棄(qi)(qi)掉的(de)(de)銅(tong)(tong)(tong)屑（銅(tong)(tong)(tong)材的(de)(de)產(chan)出比(bi)為50%左右(you)），一(yi)般廢(fei)(fei)(fei)銅(tong)(tong)(tong)供應(ying)較穩(wen)定，廢(fei)(fei)(fei)銅(tong)(tong)(tong)可以分為：裸雜銅(tong)(tong)(tong)：品(pin)位在90%以上；黃雜銅(tong)(tong)(tong)（電線）：含(han)銅(tong)(tong)(tong)物料(liao)（舊馬(ma)達、電路板）；由(you)廢(fei)(fei)(fei)銅(tong)(tong)(tong)和(he)(he)其他類似材料(liao)生產(chan)出的(de)(de)銅(tong)(tong)(tong)，也稱(cheng)為再生銅(tong)(tong)(tong)。

（2）濕法煉銅

一船適(shi)于(yu)低(di)品位的(de)(de)氧(yang)化銅(tong)，生產出(chu)(chu)(chu)的(de)(de)精銅(tong)稱為電積銅(tong)。現代(dai)濕(shi)法(fa)(fa)冶(ye)煉有硫酸化焙(bei)燒—浸(jin)出(chu)(chu)(chu)—電積，浸(jin)出(chu)(chu)(chu)—萃取—電積，細菌浸(jin)出(chu)(chu)(chu)等(deng)法(fa)(fa)，適(shi)于(yu)低(di)品位復(fu)雜礦、氧(yang)化銅(tong)礦、含銅(tong)廢礦石的(de)(de)堆浸(jin)、槽浸(jin)選用或就地浸(jin)出(chu)(chu)(chu)。濕(shi)法(fa)(fa)冶(ye)煉技(ji)術正在逐步推(tui)(tui)廣，預計本(ben)世(shi)紀末可達總產量(liang)的(de)(de)20%，濕(shi)法(fa)(fa)冶(ye)煉的(de)(de)推(tui)(tui)出(chu)(chu)(chu)使銅(tong)的(de)(de)冶(ye)煉成本(ben)大大降低(di)。