Unit 2 Raw materials for the production of iron

1、SMM, NEU2022-3-621raw material原料原料2iron-bearing material含鐵原料含鐵原料3fuel燃料燃料4flux熔劑，造渣劑熔劑，造渣劑5mineralogical礦物學(xué)的礦物學(xué)的6sinter燒結(jié)燒結(jié)(v)；燒結(jié)礦；燒結(jié)礦(n)7pellet球團(tuán)礦球團(tuán)礦8oxide氧化物氧化物9sulphide硫化物硫化物10sulfur硫硫11carbonate碳酸鹽碳酸鹽12magnetite磁鐵礦磁鐵礦13hematite赤鐵礦赤鐵礦14limonite褐鐵礦褐鐵礦15ilmenite鈦鐵礦鈦鐵礦16siderite菱鐵礦菱鐵礦17pyrite黃鐵礦黃鐵礦1

2、8pyrrhotite磁黃鐵礦磁黃鐵礦SMM, NEU2022-3-6319ferrous含鐵的，亞鐵的含鐵的，亞鐵的20ferric鐵的，三價鐵的鐵的，三價鐵的21gangue脈石脈石22titanium鈦鈦23hydrous含水的含水的24reducible可還原的可還原的25rock巖石巖石26crystallization結(jié)晶化結(jié)晶化27water of crystallization結(jié)晶水結(jié)晶水28alumina氧化鋁氧化鋁29charge爐料爐料(n)；裝爐，裝料；裝爐，裝料(v)30agglomerate結(jié)塊，燒結(jié)結(jié)塊，燒結(jié)31pelletize使成顆粒狀使成顆粒狀32grate

3、箅條，固定篩箅條，固定篩33ignite著火，點火著火，點火34frit熔融熔融(化化)35particle粒子，極小量粒子，極小量36pulverize使使成粉末成粉末SMM, NEU2022-3-6437pulverized粉狀的粉狀的38ultrafine極其細(xì)小的極其細(xì)小的39concentrate精礦，精煤精礦，精煤40binder粘合劑粘合劑41green pellet生球生球42shaft-type furnace豎爐豎爐43kiln窯窯44rotary kiln回轉(zhuǎn)窯回轉(zhuǎn)窯45permeability滲透，滲透性滲透，滲透性46storage儲藏儲藏47swell膨脹膨脹48s

4、tick粘住，粘貼粘住，粘貼49metallic金屬的，含金屬的金屬的，含金屬的50carburize使?jié)B碳使?jié)B碳51strength強(qiáng)度強(qiáng)度52structural結(jié)構(gòu)結(jié)構(gòu)(上上)的的53soft coal煙煤煙煤54hard coal無煙煤無煙煤SMM, NEU2022-3-6555injection噴吹，噴射噴吹，噴射56pulverized coal injection噴煤噴煤57dramatically鮮明地，顯著地鮮明地，顯著地58coke rate焦比焦比59approach方法，途徑方法，途徑60advance進(jìn)步，進(jìn)展進(jìn)步，進(jìn)展61limestone石灰石石灰石62ash灰分

5、灰分63drain排出，流掉排出，流掉64sulphur holding power脫硫能力脫硫能力65fluidity流動性流動性66portion部分，一份部分，一份67dependency依靠，依賴依靠，依賴68harden使變硬，使堅強(qiáng)使變硬，使堅強(qiáng)69traveling grate移動床移動床70compound化合物化合物71chemical composition化學(xué)成分化學(xué)成分72reddish淡紅色的，微紅的淡紅色的，微紅的SMM, NEU2022-3-66 The raw materials for the production of iron in the blast f

6、urnace can be grouped as follows: Iron-bearing materials, fuels and fluxes. The major iron-bearing materials are iron ores, sinter and pellet in the blast furnace. Their function is to supply the element iron, which is 93 to 94 percent of the pig iron produce. Iron ores are classed by their chemical

7、 compositions, such as oxides, sulfides, carbonates, etc, as shown in the table below.Chemical composition of pure mineralCommon designationMagnetiteFe3O4Ferrous-ferric oxideHematiteFe2O3Ferric oxideIlmeniteFeTiO3Iron-titanium oxideLimonitenFe2O3mH2OHydrous iron oxideSideriteFeCO3Iron carbonatePyrit

8、e (iron pyrites)FeS2Pyrrhotite (magnetic iron pyrites)FeSIron sulphidesSMM, NEU2022-3-67 Hematite is one of the most widely used ores. If pure, it would give 70% iron. The typical reddish color is caused by the iron (III). In the case of red iron ore, the compound of iron and oxygen is not so “tight

9、” that the hematite is regarded as “easily reducible”. Magnetite, a magnetic iron ore, is increasing in use for two reasons. Firstly, it can be separated from the rock by magnetic means; secondly, it has high iron content. Iron and oxygen atoms are very closely combined with each other in magnetite,

10、 thus making magnetite “difficult to reduce”. Limonite is a brown iron ore and contains water, which means that the iron oxides have formed a stable compound with water (water of crystallization). Containing 30 to 40% Fe, siderites are relatively easy to reduce. Most ores contain only 50 to 60% iron

11、 because they contain 10 to 20% gangue (which consists mostly of alumina and silica). If the gangue contains mainly lime, the ore is “basic”; if silicon oxide (SiO2) predominates, the ore is “acid”.SMM, NEU2022-3-68 The portion of the ore that is too fine to be charged directly into blast furnace is

12、 usually agglomerated. The most important processes are: sintering and pelletizing. The sintering process is in five stages: (1) mixing of the raw materials and fine coal/or coke, (2) placing the mixture on a grate, (3) igniting and sintering. Air drawn through the mixture burns the fuel at a temper

13、ature high enough to frit the small particles together into a cake so that they can be charged into the blast furnace satisfactorily, (4) cooling, (5) crushing and screening before charging to the furnaces. For best results, pulverized flux is added to the sinter mix to combine with the gangue of th

14、e ore in the sintering process. Sinter usually contains 50 to 60% iron. During pelletizing, the mixtures made from ultrafine (minus 0.074mm or minus 200 mesh) iron ore concentrates and binders of grain sizes far less than 1mm are balled to form “green” pellets slightly larger than 6mm but smaller th

15、an 15mm in diameter. The green pellets SMM, NEU2022-3-69are then hardened by firing in a shaft-type furnace or rotary kiln or on a traveling grate. Pellets usually contain from 60 to 67% of iron. Compared with lump ores and sinter, the advantages of pellets are: a narrow size range, constant quality

16、 and good permeability during reduction. Furthermore, pellets are well suited for transport and storage. But, any swelling and sticking of pellets during the reduction phase must be avoided. The fuels enter the blast furnace as coke, coal, oil or gas. They are used for producing the heat required fo

17、r smelting, and reducing the iron oxides into metallic iron and carburizing the iron (about 40 to 50 kilograms per ton of iron). In addition, because the coke retains its strength at high temperature, it provides the structural support that keeps the unmelted burden materials from falling into the h

18、earth. SMM, NEU2022-3-610 At present, some of the coke in the blast furnace is usually replaced by coal. The blast furnace can inject hard coal, soft coal and mixed coal. BF pulverized coal injection can dramatically reduce coke rate and the dependency on increasing shortage of coke resource, so it

19、is the most effective approach to reducing the ironmaking cost and has become an important part in BF ironmaking technology advances. Fluxes include limestone, dolomite and lime mainly, whose major functions are to combine with the ash in the coke and the acid gangue in the ores to make a fluid slag

20、 that can be drained readily from the furnace hearth. The ratio of basic oxides to acid oxides must be controlled carefully to preserve the sulphur-holding power of the slag as the fluidity.SMM, NEU2022-3-611What are raw materials for the production of iron at the BF?Why is magnetite increasing in u

21、se of iron making?Can you describe the sintering process?What are functions of the coke?What coals can be injected in the blast furnace?Why must the ratio of basic oxides to acid oxides be controlled carefully?What are the advantages of pellets compared with lump ores?What is some of the coke in the

22、 blast furnace usually replaced by at present?What do fluxes mainly include?SMM, NEU2022-3-612 1. 煉鐵原料煉鐵原料 2. 易還原礦石易還原礦石 3. 酸性脈石酸性脈石 4. 堿性脈石堿性脈石 5. 球團(tuán)礦球團(tuán)礦 6. 含鐵原料含鐵原料 7. 噴煤噴煤 8. 磁鐵礦磁鐵礦 9. 赤鐵礦赤鐵礦 10. 焦炭灰分焦炭灰分 11. 燒結(jié)礦燒結(jié)礦 12. 熔劑熔劑SMM, NEU2022-3-6131. The major iron b_ materials are iron ores, sinter an

23、d pellets.2. Iron oxides are always mixed with impurities which are called the g_.3. If the gangue contains mainly lime, the ore is b_.4. H_ is one of the most widely used ores.5. L_ is a brown iron ore.6. The portion of the ore that is too fine to be charged directly is usually a_.7. Compared with

24、lump ores, p_ have a narrow size range, constant quality and good permeability during reduction.8. The f_ enter the blast furnace as coke, coal, oil or gas.9. Fluxes include l_, d_ and lime mainly.SMM, NEU2022-3-614Hematite is _ (one; a; an) of the most widely used ores. If pure, would give 70% iron

25、. The typical reddish color is caused by the iron (III). In the case of red iron ore, the compound of iron and oxygen _ (are; am; is) not so “tight” and so the _ (magnetite; hematite) is regarded as “easily reducible”.Iron and oxygen atoms are very closely _ (combined; combining; combines) with each

26、 other in magnetite, thus making magnetite “difficult to reduce”. Limonite _ (is; are; was) an brown iron ore. It contains water, which means that the iron oxides have formed a stable compound with water (water of crystallization).SMM, NEU2022-3-6151. Iron ores are classed by their chemical compositions, such as oxides, carbonates