外文翻譯---波特蘭水泥的原料準(zhǔn)備

1、<p><b>　　外文資料翻譯</b></p><p>　　Portland Cement Preparation of Raw Materials</p><p>　　1. Crushing</p><p>　　The raw materials as received from the mines are in lump for

2、m and have to be crushed before fine grinding. The size of the lumps would depend upon the raw material and the method of mining, so the size of the crushing equipment used would depend primarily upon the size of the lum

3、ps received. In a modern cement factory, manufacturing 1000 to 2000 tonnes of cement per day, the limestone is mined by mechanical means and hence the size of individual pieces may be 1 meter or so. In smaller factories,

4、</p><p>　　(a) Limestone Crushers: The requirement of limestone per day for a 2000 TPD factory may be about 2600 to 3000 TPD, for a 1000 TPD factory 1300 to1500 TPD and for a 300 TPD factory 400 to 450 TPD. A

5、s the mining operation has to be carried out in daylight hours only, the crushing operation should also be carried out in the 10 or 12 hours of light per day. The capacity of a limestone crusher for a 2000 TPD factory ma

6、y be 300 TPH, for a 1000 TPD factory 150 TPH and for a 300 TPD factory 50 TPH. The </p><p>　　Dumpers--Feed Hopper with Laminated conveyor at the bottom 300 TPH Jaw Crusher (feed size 1000 mm - product size 2

7、00 mm ) 300 TPH Hammer Crusher or Impact Crusher or Cone Crusher (feed size 200 mm -- product size 20mm 300 THP Vibrating screen accepts minus 20 mm -- oversize back to crusher.</p><p>　　Proper dedusting arr

8、angements must be made at the crushers, the vibrating screen and the transfer points and a Dust Collector with fan installed. Power consumed for the crushing operation may vary from 3 to 6 Kwh per tonne of limestone. (b)

9、 Other Crushers. Crushers required for crushing shale, gypsum, coal, etc. may be of suitable design, preferably Hammer Mills, and of suitable size. For the 2000 TPD factory requiring 10 % addition of shale to the raw mix

10、, using the dry process and using 6 % gy</p><p>　　2.Storage of Raw Materials</p><p>　　Limestone in lump form is generally not stored at the factory, it is crushed as soon as it is received at th

11、e factory or even crushed at the mine itself and only crushed limestone is store at the factory. Shale or other corrective materials, coal and gypsum are generally stored in lump form as well as in crushed form. It would

12、, therefore be advisable to have a common covered storage space for all types of crushed materials with proper partitions and proper reclaiming arrangements, Shale, gypsum,</p><p>　　(a) crane gantry with Ele

13、ctric Overhead Travelling (EOT) cranes and </p><p>　　(b) Storage bins with overhead feed belt conveyors and underground reclaiming belt conveyors, the second alternative may be more economical both in first

14、costs and operating costs. The latest development in the storage of crushed raw materials, especially for factories with annual capacities of 0.5 million tonnes or more, is the "Bed Blending System" in which cr

15、ushed limestone from different faces of the mines and correctives are spread in predetermined layers at one end and the material reclaim</p><p>　　3.Fine Grinding</p><p>　　In the manufacture of P

16、ortland Cement types, the calcareous constituent have to combine with the argillaceous constituents are ground and the more intimately they are mixed, the more efficient would be combination. If the limestone is of cemen

17、t grade composition, the argillaceous constituents are intimately dis-seminated in the calcareous matrix, such a raw material can be ground coarse; but if the calcareous constituent is very pure and considerable amount o

18、f clay or shale has to be added, the </p><p>　　4.storage of Ground Material</p><p>　　In the wet process the ground slurry is stored either in silos or in basins with continuous mixing. The stora

19、ge capacity should be 2 to 3 days' consumption for the factory. In the dry process, tall silos are used for storage of the dry raw meal. It is now the general practice that mixing silos or "homogenising silos&qu

20、ot; are placed above the storage silos, so that the ready mixed and corrected raw mix is fed to the storage silos by gravity, result in a saving in power. The various methods of feeding</p><p>　　5.Coal Grind

21、ing</p><p>　　As coal has been considered a raw material, grinding of coal should also considered in this section. Coal has to be ground dry. Raw coal always contains 2% to 10% moisture; during the rainy seas

22、on the moisture content always goes up, sometimes even up to 15% to 20%. Therefore, coal has to be dried suitably before grinding. In early days rotary driers were used, but some forty years ago, mills were designed in w

23、hich the coal could be dried and ground simultaneously with the help of hot air, in ai</p><p><b>　　6.Burning</b></p><p>　　A mixture of pure lime and silica in the proportion of 2. 8:

24、1 should give 100% tricalcium silicate on burning, but it will require a very prolonged heating at 1600℃ or more, to obtain a perfect combination. It is not possible to obtain such prolonged heating conditions in actual

25、plant practice; it is, therefore, necessary to add some fluxing materials to bring about the combination at a lower temperature and in a shorter time. Alumina, iron oxide and, to some extent, magnesia and alkalies presen

26、</p><p>　　Clinker burning takes place in the above mentioned sequence in all the processes of burning, viz. , Long Dry Process Kiln, Long Wet Process Kiln, Short Dry Process kiln with suspension preheaters a

27、nd Short Kilns with great heat exchangers. Lime silicates (C2S and C3S) are the true cementations materials, C3S contributing towards early strength and C2S towards late strength, so the Process Chemist tries to obtain t

28、he highest possible C3S and lowest possible free lime in his clinker commensurate w</p><p>　　波特蘭水泥的原料準(zhǔn)備</p><p><b>　　破碎</b></p><p>　　作為從礦山得到的原料以塊狀形式（存在），必須在研磨之前被破碎。 塊狀的大小

29、取決于原料和采礦的方法，因此，所用破碎設(shè)備的尺寸（規(guī)格）將主要地取決于收到的塊狀大小。在一個(gè)現(xiàn)代化的水泥工廠,每天生產(chǎn)（日產(chǎn)）1000到2000噸的水泥，石灰石采用機(jī)械的方法（手段）挖掘，因此個(gè)別的塊大小可能達(dá)到1米左右。在較小的工廠，石灰石的采礦可能是人工的，個(gè)別塊的大小可能達(dá)到200毫米左右。同樣地,粘土、頁巖、（鋁）礬土、紅土（鐵礬土）、，沙巖、煤、石膏等，其大小一般不超過300毫米。</p><p>　　

30、(a)石灰石破碎：一個(gè)2000TPD的工廠每天石灰石的需求量可能是2600到3000TPD；一個(gè)1000TPD的工廠每天石灰石的需求量可能是1300到1500TPD；一個(gè)300TPD的工廠每天石灰石的需求量可能是400到450TPD。由于采礦操作必須在白天進(jìn)行,破碎操作也應(yīng)該在白天的10或12個(gè)小時(shí)內(nèi)進(jìn)行。一個(gè)2000TPD的工廠石灰石破碎機(jī)的能力可能是300TPH；一個(gè)1000TPD的工廠是150 TPH；一個(gè)300TPD的工廠是50

31、TPH。石灰石破碎機(jī)的選型取決于石灰石的物理性質(zhì)，然而，對(duì)于用人工挖掘石灰石的小型工廠, 單段錘式破碎機(jī)是最適當(dāng)?shù)?，但?duì)于比較大的工廠，二級(jí)破碎總是更經(jīng)濟(jì)和更有效率，第一個(gè)階段可以是顎式破碎機(jī)、轉(zhuǎn)子破碎機(jī)或沖擊破碎機(jī)，第二個(gè)階段破碎為錘式破碎機(jī)或圓錐式破碎機(jī)。如果可能，適當(dāng)尺寸的篩子應(yīng)該用于二級(jí)破碎以便只允許小于（篩孔）尺寸的物料通過而大塊物料繼續(xù)破碎。一個(gè)典型的2000 TPD石灰石破碎生產(chǎn)線流程應(yīng)該是：</p><

32、;p>　　底部裝有薄板傳送帶的卸料斗；300TPH 顎式破碎機(jī)(原料大小1000毫米、 產(chǎn)品大小200 毫米)；300 TPH 錘式破碎機(jī)或沖擊破碎機(jī)或圓錐破碎機(jī)(原料大小200毫米、產(chǎn)品大小20 mm )；300THP振動(dòng)篩-允許小于20毫米通過—太大的返回破碎機(jī)。</p><p>　　破碎機(jī)、振動(dòng)篩和轉(zhuǎn)向點(diǎn)必須安排適當(dāng)?shù)某龎m，收塵器安裝有風(fēng)機(jī)。破碎作業(yè)的能耗變化很大，從3到6 Kwh/噸石灰石。<

33、/p><p>　?。╞）其它的破碎。頁巖、石膏和煤等的破碎必需使用破碎設(shè)備，使用錘式磨機(jī)及適當(dāng)?shù)拇笮。ㄒ?guī)格）可能是適當(dāng)?shù)脑O(shè)計(jì)。對(duì)于2000 TPD的工廠，原料混合物中需要加入10%的頁巖，使用干法生產(chǎn)（工藝）以及水泥磨中加入6%石膏，頁巖 </p><p>　　的需求量大約為300TPD、煤400TPD 和石膏100TPD。破碎機(jī)較好的大?。ㄒ?guī)格）將分別地是30TPH，50TPH和 20TPH

34、，原料粒度規(guī)（指）定為小于300毫米，產(chǎn)品粒度為20或25 mm。</p><p><b>　　2.原料的儲(chǔ)藏</b></p><p>　　塊狀石灰石通常不在工廠儲(chǔ)存,一旦進(jìn)廠就立即被破碎，或者甚至在礦山本身就被破碎，在工廠只是儲(chǔ)藏。頁巖或其他的校正原料、煤和石膏通常最好以破碎過的塊狀形式儲(chǔ)存，因此，對(duì)所有類型的破碎過的原料，最好有公共的帶有屋頂?shù)牟⒈贿m當(dāng)分割以及適當(dāng)

35、取料-頁巖、手石膏、煤等的儲(chǔ)藏空間（聯(lián)合堆棚），收到的塊狀（物料）將被巧妙的儲(chǔ)存和排列以使相同的物料去各自的破碎機(jī)械。破碎物料儲(chǔ)庫的兩種類型通常是：(a)帶有電動(dòng)天車(EOT)的起重機(jī)，(b)帶有高空物料皮帶輸送機(jī)和地下取料皮帶輸送機(jī)的儲(chǔ)藏箱柜（儲(chǔ)庫）， 第二種選擇可能在第一費(fèi)用（基建費(fèi)用）和生產(chǎn)費(fèi)用更經(jīng)濟(jì)。在破碎的原料儲(chǔ)藏方面的最新發(fā)展-尤其是年產(chǎn)五十萬噸或更多的工廠, 是“混合床系統(tǒng)（預(yù)配料均化系統(tǒng)）”-從不同礦區(qū)來的破碎過的石灰石

36、和校正原料，從一端以預(yù)先確定的層鋪開，在另一端借助于刀片取料, 以便使預(yù)混料近似于需要的化學(xué)成分被喂到生料磨喂料斗。根據(jù)當(dāng)?shù)貧夂?，該系統(tǒng)既可有廠房，也可露天或搭棚。塊狀物料通常露天儲(chǔ)存并且借助于裝載機(jī)或鏟車或推土機(jī)取料。</p><p><b>　　3.粉磨</b></p><p>　　在波特蘭類型水泥的生產(chǎn)中，石灰質(zhì)成份必須與粘土質(zhì)成份聯(lián)合粉并且更密切地混合，（成分

37、）差別越大越要混合。如果石灰石是水泥主要成分，粘土成分密切地分布在石灰質(zhì)的點(diǎn)陣中，這樣的原料粉磨可能是地粗糙的，但是如果石灰質(zhì)成份是非常純的并且相當(dāng)量的泥土或頁巖必須加入, 混合原料必須充分粉磨。在一個(gè)試驗(yàn)工廠進(jìn)行的一些測(cè)試表明了詳細(xì)的原料混合所需要的最適宜的研磨程度。供應(yīng)給磨機(jī)的原料一般小于20毫米、產(chǎn)品細(xì)度應(yīng)該是90微米篩子的篩余為13±7%-這必須被記住。密切的混合是另一個(gè)重要因素，原料的混合不得不帶進(jìn)大量氧化物成分，在

38、水泥的生產(chǎn)中通常通過簡(jiǎn)單的酸/堿滴定測(cè)量確定總碳酸鹽(TC)。 舉例來說，如果在一間工廠把握的TC是78%，每一批的TC變化量不應(yīng)該超過78±0.1% ，而且這可能只有通過完全的混合來實(shí)現(xiàn)。</p><p><b>　　4.生料儲(chǔ)存</b></p><p>　　在濕法生產(chǎn)（工藝）中，粉磨的生料漿既可儲(chǔ)存在生料（料漿）庫和帶連續(xù)混合的料漿池中，儲(chǔ)存能力應(yīng)該是工

39、廠2到3天的消費(fèi)量。在干法生產(chǎn)（工藝）中，高大的生料庫用于干生料的儲(chǔ)存，設(shè)置在儲(chǔ)存庫之上的混合庫或“均化庫”是目前通常采用的，以便預(yù)先混合并得到調(diào)整的混合生料通過重力被喂入到儲(chǔ)存庫，以節(jié)省動(dòng)力。生料漿和干生料以各種不同的方法喂入到煅燒設(shè)備，煅燒過程行為將在下面章節(jié)中討論。</p><p><b>　　5.煤的粉磨</b></p><p>　　如煤已經(jīng)被考慮為一種原料，

40、煤的粉磨也應(yīng)該在這一章節(jié)中被考慮。 煤必須是干法粉磨。原煤總是包含2%到10%的 水分；在雨季水分含量總是升高，有時(shí)高達(dá)15%到20%。這樣，煤必須在研磨之前被適當(dāng)?shù)馗稍?。早期使用回轉(zhuǎn)烘干機(jī)，但是，約在四十年前，設(shè)計(jì)出了一種借助于熱氣體對(duì)煤進(jìn)行烘干兼粉磨的磨機(jī)-風(fēng)掃磨。在烘干與粉磨單獨(dú)進(jìn)行的系統(tǒng)中，借助產(chǎn)生于油燃燒或煤燃燒或煤燃燒爐的熱氣體使物料在適當(dāng)烘干機(jī)中被干燥；廢氣通過適當(dāng)?shù)某龎m排放到大氣中。干燥過的煤然后粉磨，既可是開路煤磨-出

41、磨煤粉通過提升機(jī)輸送到煤粉燃燒料斗（倉）；也可以在圈流風(fēng)掃煤磨中粉磨，利用氣體將煤粉輸送到煤粉燃燒料斗（倉）上方的旋風(fēng)筒（分離器），同樣的氣體被用作煤粉燃燒器（噴煤管）的一次風(fēng)。在烘干兼粉磨系統(tǒng)，磨機(jī)的前一部分安裝有匹配的揚(yáng)料板和鏈條，其作用如同回轉(zhuǎn)烘干機(jī)，后一部分裝有鋼球，其作用如同閉路磨機(jī)；熱風(fēng)即可以來自于回轉(zhuǎn)窯，也可以來自于輔助爐子（熱風(fēng)爐）。在這種情況下，廢氣也可以用作煤粉燃燒器（噴煤管）的一次風(fēng)。單獨(dú)烘干和粉磨的單位能耗每噸成

42、品煤可能消耗25到30 kW·h，烘干兼粉磨的單位能耗每噸成品煤可能消耗20到25kW·h。</p><p><b>　　6煅燒</b></p><p>　　純粹的石灰和硅石以2.8:1的比例混合在煅燒過程中應(yīng)該生成100%的硅酸三鈣，但是當(dāng)加熱到1600℃或更高（溫度）將需要很長(zhǎng)（時(shí)間）才能獲得完全反應(yīng)。在工廠實(shí)際生產(chǎn)中，獲得如此長(zhǎng)時(shí)間的高溫條件

43、是不可能的，因此，加入一些熔劑材料使化合在較低的溫度和在短時(shí)間內(nèi)（進(jìn)行、完成）是必需的。礬土（氧化鋁）、 氧化鐵，一定程度上，氧化鎂和堿代替熔劑出現(xiàn)在生料中。通過（采用）在生料中明智的包含這些氧化物（的方法），工廠實(shí)際生產(chǎn)過程中，在可能達(dá)到的溫度范圍內(nèi)將反應(yīng)時(shí)間縮短到合理的極限內(nèi)是可能的。 在水泥生產(chǎn)的煅燒過程中，生料首先被加熱到大約100℃，這時(shí)干生料或半干法料球或濕法料漿中的水分離開（蒸發(fā)）。 干的生料被更進(jìn)一步加熱并達(dá)到大約400