爐(lu)(lu)(lu)渣(zha)(zha)的(de)(de)(de)組分(fen)靠(kao)加入(ru)適量的(de)(de)(de)熔劑(石灰、石英石、螢石等(deng))進(jin)行調整。在冶(ye)煉(lian)過(guo)程(cheng)中(zhong)通過(guo)對爐(lu)(lu)(lu)渣(zha)(zha)組分(fen)和(he)性質的(de)(de)(de)控(kong)制,能使脈石和(he)氧(yang)(yang)化(hua)雜(za)質的(de)(de)(de)產物與熔融金(jin)屬或硫順(shun)利分(fen)離,脫除金(jin)屬中(zhong)的(de)(de)(de)害雜(za)質,吸(xi)收液態金(jin)屬中(zhong)的(de)(de)(de)非金(jin)屬夾雜(za)物不直接受(shou)爐(lu)(lu)(lu)氣污染,富集有用的(de)(de)(de)金(jin)屬氧(yang)(yang)化(hua)物;在電爐(lu)(lu)(lu)冶(ye)煉(lian)中(zhong)還是電阻發熱體。爐(lu)(lu)(lu)渣(zha)(zha)在保(bao)證冶(ye)煉(lian)操作(zuo)順(shun)利進(jin)行、冶(ye)煉(lian)產品質量、金(jin)屬回收率等(deng)各(ge)方面起著(zhu)決定(ding)性作(zuo)用,例如煉(lian)鋼(gang)作(zuo)業中(zhong)有"煉(lian)好(hao)渣(zha)(zha),才(cai)能煉(lian)好(hao)鋼(gang)"的(de)(de)(de)說法。
根據(ju)冶金(jin)過程的不同,爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)可分為熔煉渣(zha)(zha)(zha)(zha)(zha)、精(jing)煉渣(zha)(zha)(zha)(zha)(zha)、合成渣(zha)(zha)(zha)(zha)(zha);根據(ju)爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)性(xing)質,有(you)堿性(xing)渣(zha)(zha)(zha)(zha)(zha)、酸性(xing)渣(zha)(zha)(zha)(zha)(zha)和中(zhong)性(xing)渣(zha)(zha)(zha)(zha)(zha)之分。許(xu)多爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)有(you)重要(yao)用(yong)(yong)處。例如(ru)高(gao)爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)可作(zuo)水(shui)(shui)泥(ni)原(yuan)料(liao);高(gao)磷渣(zha)(zha)(zha)(zha)(zha)可作(zuo)肥料(liao);含(han)釩、鈦渣(zha)(zha)(zha)(zha)(zha)分別(bie)可作(zuo)為提煉釩、鈦的原(yuan)料(liao)等。有(you)些爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)可用(yong)(yong)來制(zhi)爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)水(shui)(shui)泥(ni)、爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)磚、爐(lu)(lu)(lu)渣(zha)(zha)(zha)(zha)(zha)玻璃等。
煤(mei)在(zai)鍋(guo)爐燃燒室中產生的熔融物,由煤(mei)灰組成。可(ke)作磚、瓦等原料。
火(huo)法(fa)冶(ye)金(jin)(jin)過程(cheng)中(zhong)生成(cheng)(cheng)的以氧化物(wu)(wu)(wu)(wu)為(wei)主的熔(rong)(rong)體;它是鋼鐵(tie)、鐵(tie)合金(jin)(jin)及(ji)有(you)色重(zhong)金(jin)(jin)屬(shu)(shu)冶(ye)煉(lian)和精煉(lian)等(deng)(deng)過程(cheng)的重(zhong)要產(chan)物(wu)(wu)(wu)(wu)之(zhi)一。主要成(cheng)(cheng)分(fen)是CaO、FeO、MgO、MnO(堿性氧化物(wu)(wu)(wu)(wu))等(deng)(deng),SiO2、P2O5、Fe2O3(酸性氧化物(wu)(wu)(wu)(wu))等(deng)(deng)及(ji)Al2O3(兩性氧化物(wu)(wu)(wu)(wu));此外,經常含(han)(han)有(you)硫化物(wu)(wu)(wu)(wu),如鋼鐵(tie)冶(ye)煉(lian)爐(lu)渣(zha)中(zhong)含(han)(han)有(you)少(shao)量CaS,有(you)色重(zhong)金(jin)(jin)屬(shu)(shu)冶(ye)煉(lian)爐(lu)渣(zha)中(zhong)有(you)時含(han)(han)有(you)較多FeS、Cu2S或 Ni3S2等(deng)(deng);爐(lu)渣(zha)中(zhong)還(huan)夾帶少(shao)量金(jin)(jin)屬(shu)(shu);個(ge)別強還(huan)原性爐(lu)渣(zha)含(han)(han)有(you)CaC2。在冶(ye)金(jin)(jin)過程(cheng)中(zhong),熔(rong)(rong)融(rong)(rong)爐(lu)渣(zha)與熔(rong)(rong)融(rong)(rong)金(jin)(jin)屬(shu)(shu)、熔(rong)(rong)融(rong)(rong)鐵(tie)合金(jin)(jin)、熔(rong)(rong)锍及(ji)爐(lu)氣等(deng)(deng)產(chan)物(wu)(wu)(wu)(wu)之(zhi)間(jian)起著各種(zhong)物(wu)(wu)(wu)(wu)理(li)化學反(fan)應,達到該過程(cheng)所預期的冶(ye)金(jin)(jin)目(mu)的。由于(yu)爐(lu)渣(zha)與金(jin)(jin)屬(shu)(shu)或熔(rong)(rong)锍間(jian)的溶解度小以及(ji)兩者比重(zhong)不同(tong)而(er)得(de)與分(fen)離。依據組成(cheng)(cheng)不同(tong),熔(rong)(rong)渣(zha)冷(leng)凝后成(cheng)(cheng)為(wei)巖石(shi)狀或玻璃狀物(wu)(wu)(wu)(wu)質。