英文翻译

　专 业 材料科学与工程 学生姓名

　班 级 材料 1 班 学号

　指导教师

　完成日期

　原文

　? 60 ,

　Llnder the best efficiency conditions*

　A+ keeping the diaphragm openin^s θf PrOPer SiZeeS CIean

　B* keeping the Ioadjng Of the individual ChamberS Of the null trim size — WiSe and Weight—WiSe

　C. keeping the mill as drafεy as POSSible

　D? USing USefUl dust and grinding aids

　2. With a cement temperature Of

　, rhe production Qf a CenIent mill

　may be the highest.

　80€ 氏 IOo C e 12θuc D more than 120cC

　3* According to the PaSSage, to OPerate the Cement Tnill efficiently as POSSibieT the following StePS must be t?ken EXCEP I'

　,

　allowing the Clinker to CoOl and mature as much as POSaibIe befyre grinding.

　USing Watet SPray InSide and OUtSide the mill.

　CH IlOt USing Water SPray because this mill deteriorate the Cunken

　D- maintaining a Very high draft th∏ UlgII Ihe mill.

　4. AcCording !o Ihe PaSSage thυ PoWPr CarISUnoption may be

　Per

　toιme by applying a two—Stage grinding.

　A. 45 kWh B. 30 kWh C 7 kWh D 23 kWh

　5* The SeCOnd formular Q=Q) X (B0∕B) X (S√5)1,3 indicates

　A. that output Of the mill in tonnes Per hour would vary dιrceitly as the Bond IndCX Of the materials.

　B- IhaI the OUtPUt Of the TnJIl in tonnes Per hour WOUId Vary directly RS Ihe POWer *in' Of the SPCCifiC SUrfaCei

　that tht OUtPUt Of the πιill in tonnes Per hour WOUlcl Vary IndireCtly as the BQnd IndeX Of the materials and to POWer 勺” Of the SPeCifiC surface.

　H NOrLe Of the above.

　Reading PaSSage Il

　ChemiStry Of POrtIand CCmelItS

　POrtIand CementS are made hy LgrlitLng a finely ground TrLiXtLlre Of a Iinle bearing Tnaterial SIICh as calcium Carbonate Or CaklLIm su?hate and aluminium WiIiCat已,SUCh as ClSy Or Ilaterite T in ?otnc d^fιπιre PredetermiIIed PrOPOrtiOT)S T COOLtng the PrOdIlCt Of Slntering, CalleH "clinkerr in CCmenl technology T and

　*

　* 61 ?

　grinding it Witb the addition Of SOme Pr(^)OrtiOn Of gypsum. POrtland CernentS appear to be Very PrOSaiC CnaterjaIS t hut It WDUId not be incorrect to way that each type is a definite fine ChemiCal and the Paine Care has to be taken in. manufacturing any type Of POrlIanel Cement as is neces?ary for the manufacture Of a fine CbCrniCaL as a Tmtter Of fact, at ICaSt thirty ChelniCal engineering Unit OPerations are entailed in rhe manufacture Of CenIent? All POrtIand CeniEntS are Inade from IiIneStone； Ihere are Very few factories Where by - Pr(XlUCt CaICiUm CarbOnate SlUdge Or gypsum Or anhydride is USed as the main raw materiaL Tne range Of OXilIe 匸ClTnpOBtion And institution Or COmPOLJn(I CPomPOSitiolI Of POrtIarLd CCnIent Cllnker ( except WI-Iite Ceniciil CIiJIker and Oil Well (Zenlent CIiIIker) are given in Table L

　TabIe 1

　SiOi

　22±4?

　QAF

　H ±4%

　AlA

　5±2%

　C3A

　田％

　Fe2O3

　吐Z 5%

　C3S

　40+10%

　CaO

　64 士 2%

　GS

　35±10%

　MgO

　3±2%

　Freelime

　1±1%

　AlkaliH

　O. 8±0. 3%

　SOJ

　O" 5+0. 2%

　OXide COmPOSitiOn

　CoclStitUtLOrt

　The exact ChemiCal COiTlPaSLtiOn Of the Clinker to be PrOdUCed at a factory WiII depend UPOn the type of raw materials and fuel available. The CalCareOIIS rawmaterials Tnay be IimeStOneT marl, CaLCareoUS Sea AandT Se日 ShellSt COral Or byproduct CalCLUnl CarbOnate； the argillaceous raw materials nιay be Clay ? Shale Or Iaterite, Son?et lines Very Sma11 PrOPorhOnS Of iron Ore Or SalIdStOne Inay have to be added to bring UP the ChCIniCal composition Of the raw Hlix to Lhe CXaCt pre- detem∏ined ConlPO?itιon< The fuel used may be COal ? fuel Oil Or natural 前轧 It rτuιsi be remeπιbered that a Part Of IiIe asb PreSem LIl COal is added to the Cement raw mix during burning and hence its ChenliCal ComPQSition should be raken into COnSlderatiojI While designing the raw mix.

　A typical example Of designing a POrtland CellIent CIJnker is given below. The CIinker has to have the following constitution；

　?

　? 62 ?

　TabIe 2

　GΛF

　10?

　CiA

　10%

　cλs

　47%

　CZS

　28%

　Mg()

　4%

　FreeIinle

　1%

　100 K

　Γhιs type Of CIinkrr IS ideal for InAking Ordinary Pordand Cement,

　(a) TriCalCinm SiIiCate (C5S) is the Inam StrerIgth RiVing ComPoUnd in a Portland C?3merit f it contributes towards early Strength； On the Other b?nd, Di- CalCiUm SibCatC (C?S) COntribUteS towards IatCr strength. Citnker with Very high JX^tentjal C3St however? LS difficult to burn in the CQnVentiOnaI burning equip- nwt available to t?e industry at PreSCnt t So in Ordinary POrTIanCl cement Che ProPOrtiOn Of CaS is PrCknibIy kept between 40% and 50? and CES between 25% and 35%* In RaPid Hardening Cement and in (Ml WeII Cerrkent T the GS must be kept more than 50% * at about 50% to 6D?, SO that high early StrerLgthS Can be attained. To enable the CIilIker to be burnt PrOPerly it IS neces- 晚Lry to add sσι□t HUXing agent to the raw mix； alumina (Al2O3) and iron OXide CFeKOS) act as fluxing agents* On burning, t]ιc ALO4 and Fc-(? PreSent in a TaW mix first form C4AF and ClA On hydration generate more heat and the PreSCnCe Of a higher ProPOrtkm Of Λ in ? CCnlent makes it IeSS resistant to SUIPhitTC ac- ti<m. 1 Herefore t in MOderate Heat POrtIand Cement the CjS COntent is kept a Iio tie IOWer and the C3A Content 訪QUlei be below 8?. In SUIPhate ReSiSting Ce- m<int GS Tnay be kept as Iligh as high as in Ordinary PCnland Oinent but the QA COntent must be kept betow 5%. In LOW Heat Cement both CIS and CiA must be kept IoW as POSSible , at about 30% and fi? resppctively. In Oil Wdl Cement t as mcntioιwd before t the C?S COntent must be kept higher than 50%， but GA COntetlt ShoUltl be kept below 3 % J Preferably near about 0%( but the CdAF ~2C3A COntent ShOLdd be below 20%. In WllLte CemCnt the Fe2O3 must be below O* 4%i

　?b) ThUS it WiU be SCen that for marιufactυring any Of the above types Of cement ? it WiIl first be nprG?sary W decide IlpGlrι the CQnlPQUn(I ConlPoSitiOn Of the CCnlCn1, and from IhiS ihe OXide c<∣mpos∣ιion Can be cakυlated as IlaS b亡Cn explained. In the OXide COInPclSitLOn the factors.

　SLO√R2(?i AlQ√Σ?O,

　?

　?63?

　bi S. F, and Si S. F. have been indicated. TlIeSe factors have COnSiderabIe effect On the burnability Of a raw mix. IrL a COrreCtIy CieSiglled r3w mix COmPaSed Of CaC)* SiO2, Al3iOs ≡ FeEo3 and Mg<‰ during the PrOCeSS of burning, all the Fe2O? and a Part Of ΛLO3 first CCJmbine WJtb CriO to form C^AF； Ihe remaining AhC? then COmlJineS VHTh a ParT Qf Cao to (Orm A； WhLCh twn (G4AF and CIA) act as fluxes to form SLIiCateK- All the Sior then PreSent in the raw IlUX COnIbineS With a t?∣rt Of Cao to {0r∏1 C；S and SOnie Cno is S(III Ieft UnCOTnbined. ThiS ιιn- c□rπbincd CaI) Ihen COmbineS WIth a PItrt Of GS already formed to form C3S

　the IJhirnaltJy desired ComIx)Und. In a COrrCClly designed raw mix and Under PrOPer burning COnldniOnSJ no free CaO ShOUld be Ieft in Ihe clinker； but in actual PraCtiCC (λ 5% to 2. 0% free CaO is always left. The ImI)OrtanCe Of L* S. F. (Linle SatUratiOn FaCtoZ) I WhiCH UkeS into account the POtentiaI COmbining PoWer Qf S1O2? AlXDs and Fe2O3 WLth Caol COillew iτι at this point, The L* S* F、 ShOUkl be betWeen O. 66 anrl IP 02 in a POrtIand Cement t Ihe higher? UP Io s Iim- it* the better. If it is POtenIiaILy near 1*0 in a clinker, It is Very difficult to burn the CILnker SatiSfaCtOrilyt especially With IhC type CIf Coal available to the IndlarI CernerIt industry? because Of IhiS it IS better to maintain h At about (L 9. The factor StO2∕K0< is a measure for the fluxes in a eiinker t ihe IOWer (up to a Iimit)it i苦舁 hg： ben er for burning, ]t ShOUId be maintainυd between 2t OiInIl 3? OJ 2. 41 as Γotιnd tn the CIinker UnelCr discιtssion is k?fd. JVfgf) is IleCeSSariIy PreSeIit in a <?- r∏E∏i raw nιix> and hence in cement. MgC)? Ln general ? CIOeS not COiDbine With CemeIlt COmPQUndS? but it h?s SOme fluxing actioni On Ihe Other hand, it has One bad effect ” MgO When burnt at VCry high teπιjxrralures forms h?ιrd 一 burnt periclase CrySUIS in the clinker； these PeriCIaSe CryStak hydrate VCry sl∩wly over the yars and expand during hydration； thus if the CIinker COntataS MgO higher than 日 maximum SPeCified il VVill be UnSOUlId Qn hydrrition* 501 in the Indian Stalldard &pec if teat ions (Or POrtIand Cement T The TnUXiniυιn Of Mg<J has been SPeCifIeG at 6%* AtkaIieS in the form of NaZO anti KQ an<l SO^ are PrCSent to the extent Of le? than 1? in a clinker. Rarely traces Of PgCVno1* ChIOridCS and FlUOride5 are present in Some CeRlent FaW mixes.

　FhG ChetniStry of PortIand Cement has bt?en discussed in brief. It has been ' explained tlvιt POrtIand Cement is essentially composed Of TriCaIeiUnI SiliCateI Dtcalcium silicate, TriCalCiUm acuminate arid tCtracalciuiTi aluminoferrite in vary- ing ProPortiOnS J SOmC gypsum (CaICiunl SIIIPbaIe dehydrate ) is also added to COntro) the netting time； Hytlration Of tiιese CelTnPQUndS an addition Clf Water g;S SelIIrig <tπc? HattlenirLg PrOPCrtieS to Lhe Cenlerit. Γhe CflemiCai reactions i∏-

　*

　* 64 ?

　VOIVed in Setting ￡ind hardening Of CenIent are Very COmPlex, so∏?e reactions are Very fast <ιπci OtherS Very SIoW? The IrLain PrLnCiPle LinCierIying Setting and hardening all type Of POrtland Cement and Biended CenIentS (in a nutshell) LS a wnon -reversible gel formation and COagUIatiQn Of a SUSPenSLOn Of a finely CliVided soli4 PhaSe dispersed in a IiqIIid PhaSe forming two typw? Of networkst CQagUlated and CryStalline # and the IWQ IOgether forming COndenSatiOn CryStaiUSatiOn networks n. A CharaCteriStiC Of SUCh networks is that they exhibit thixotropic PrOPertieS t Or the ViSCClSity Of the PaSteS Change due to time and not due to Chjange Of temperature^

　ThT Water added to the CemenC acts OII the Cement grains To form a SHPer 一 SatUrated SolUtlOn Of CakiUm SIllCate hydrate {ro∏j WhiCh a gel 一 ILke mass Of minute CryStaIS PreCiPitate- Γhe Water reaches the Unhydrated Core Of the Cetnent grain by diffusion through the SUrfaCe film Of hydrates formed and Ibe rate Of hydration, WhiCh is Very fast iiiιtiallyt IS ?lowed down* The UnIlydrated CenIellt TnaSS and WEiter first form a PlaStiC mass, in WlliCh, Iater on. a metastable gel Of ∏ιinute CryStalS Of COllOidal dimensions COTrIPαsed Of CalCLlJm SIliCate hydrates (CSSH) and also CnrStalIinJe ProdUCtS Of above COllOidaL dimensions COmPoSed Of CalCiHm hydrate, hydrated CaICiUm acuminate and calci□rn SUIPha - aluminates are formed SimUItanCOUSIy÷ ThereI is Ihen H Partial dehydration Of the PrOdUCtS and formation Of n Stable geL

　The Change from the PIaStiC mass to SimUItaneous PrOdUCtiOn Of r∏etastable gfd and CryStalIine PrQdljICtsi takes PlaCe dυriτιg the Setting PrOCeSS Of the cen?cnι PaStc. Hardening Of the Set CeTnent PaSte is attributed to the production Of increasing amounts Of inter - twined CryStaIS LrL Ihe gel. FrhITlSt Setting Of Cement PaSte takes PIaee due to the development Of a CoagUlatiOnal CryStaIline IIetWOrk mor亡 Or IeSS thixotropic in nature； and Ilarclening Of the Set CenIent PaSle is due to development Of much Stranger and iIieversibly inter ~ twined CryStalhne StrUC- t□res>

　AdditiOn Of gypsum as a Set retarder PiayS a Very important Part in the set- tmg and hardening PrOCeSS of ErnerIι. It SerVeS as a PaCe maker iυr the hydra- tiorι Of the different Iinle COtriIx)unds in the cement PaSte by forming CalCiUrn sud- pha - BlUnIil^teSf ThUST Set and hardened Cement PaSte is COmpOSed t essential- ly, of a tobermoriτe like CaiCiUnl SiiiCate IIydrate (CJSH) PhaSel and a CaiCiUln SUIPhO - aluπιinate (GA SCaSO4 3HI?0) PhaSe t both PhaSeS Of VaryinK composition depending UPQn the CheIrUCal COnlPOSitiOn Of the cement, [?esence Qf ∏x>re Or IeSS Of IheSe OOmPQUHdS in the hardened CerDent gives different proper-

　翻译：

　硅酸盐水泥的化学成分

　硅酸盐水泥是通过煅烧一些精细混合在一起的由如碳酸钙或硫酸钙、 铝硅酸 盐、粘土或红土的这些材料组成的石灰石， 按一定明确的预定比例， 再冷却烧结 后的产物，在水泥技术上称之为“熟料” ，另外加一定比例的石膏研磨制成的。

　硅酸盐水泥看起来很平凡的材料， 但不能错误地认为是每种类型都是有相同的明 确的化学过程， 制造任何种类的硅酸盐水泥都是有需要精细的化学生产， 因为事 实上，至少有三十种化工单元操作是牵涉在水泥生产中的。

　所有的硅酸盐水泥都 是由石灰石制造的， 只有极少数的工厂是以产品碳酸钙产品、 污泥或石膏或酸酐 为主要原料。氧化物的组成成分和限制以及复合硅酸盐水泥熟料 （除白水泥熟料 及油井水泥熟料 ） 的化合物组成范围在表 1 中给出。

　表1

　氧化物组成成分

　限制

　SiO2

　22 土 4%

　C4AF

　11 土 4%

　Al2O3

　5土 2%

　C3A

　9土 4%

　Fe2O3

　3土 2.5%

　C3S

　40 土 10%

　CaO

　64 土 2%

　C2S

　35 土 10%

　MgO

　3土 2%

　游离石灰石

　1土 1%

　碱

　0.8土 0.3%

　SO3

　0.5土 0.2%

　工厂生产的熟料的确切的化学组成成分将取决于原材料和可用燃料的种类

　钙质原材料可能是石灰石、钙质海砂、贝壳、珊瑚或碳酸钙副产品；泥质原材料 可能是粘土、 页岩，有时可能添加很小比例的铁矿石或砂岩来提高原混合材料中 的化学成分到确切的预定成分。

　使用的燃料可能是煤、 石油或天然气。

　必须记住 的是当设计原混合生料时， 需考虑在燃烧过程中添加一些存在部分灰的煤到水泥 原混合材料中以及提高它的化学组成成分。

　面给出一个设计硅酸盐水泥熟料的经典例子。熟料必须有如下的限制：

　表2

　C4AF

　10%

　C3A

　10%

　C3S

　47%

　C2S

　28%

　MgO

　4%

　1%

　100%

　这种类型的熟料是制造普通硅酸盐水泥的典范。

　a)C3S 在硅酸盐水泥形成中提供主要强度，它有助于形成早期强度；另

　一方面， C2S有助于形成后期强度。然而， C3S 含量很高的熟料，在目前工业上 可用的传统燃烧设备中是不容易燃烧的。

　因此在普通硅酸盐水泥中 C3S 的比例保 持在 40%~50%之间， C2S在 25%~35%之间。在快速硬化的水泥和油井水泥中， C3S 的比例必须保持在 50%以上，大约在 50%~60%，这样才会达到较高的早期 强度。为了能使熟料完全燃烧，有必要在原混合物中添加一些助熔剂； Al2O3 和 Fe2O3 可作为助熔剂。在燃烧中，存在于原混合物中的 Al2O3 和 Fe2O3首先形成 C4AF， C3A 在水化过程中产生更多的热量，水泥中较高成分的 C3A 使得抗硫酸 性能变弱。因此，在中等热量硅酸盐水泥中 C3S的含量稍低些， C3A 的含量应低 于 8%。在抗硫酸盐水泥中 C3S 的含量可以和普通硅酸盐水泥中一样高，但必须 保持在 5%一下。在低热量水泥中 C3S和C3A 的含量都应该尽可能得低一些， 大 约分别在 30%和 60%。在之前提到的油井水泥中， C3S 的含量必须保持在 50% 以上，但是 C3A 的含量应该在 20一下。在白色水泥中 Fe2O3 的含量必须在 0.4% 以下。

　(b) 因此可以看出，制造以上任何种类的水泥，首先必须决定水泥的复合组

　成，从计算出的氧化物成分可以看出。在氧化物成分的因素中，

　SiO2/R2O3、

　Al 2O3/Fe2O3、L.S.F,和 S.S.F.已经被确认。这些因素对生料的易烧性有很大影响。

　在正确设计的由 CaO、 SiO2、Al 2O3、Fe2O3和 MgO 组成的混合原料中，在燃烧 过程中，所有的 Fe2 O3和一部分 Al 2O3首先和 CaO 形成 C4AF;剩下的 Al 2O3和一 部分 CaO形成 C3A；C4AF 和 C3A 作为作为通量形成硅酸盐。然后所有的 SiO2 存在于原混合物中和一部分 CaO 来形成 C2S，一些 CaO 仍没被组合。这些没被 组合的 CaO然后和一些已形成的 C2S 一起形成 C3S（最终目标化合物）。在一个 正确预期的原混合物中和目前可能的燃烧条件下， 熟料中不应有游离氧化钙的存 在；但实际上总是有 0.5%到 2.0%的游离氧化钙存在。

　L.S.F（石灰饱和因子）的 重要性在于考虑到 SiO2、Al2O3、Fe2O3和 CaO 结合在一起的力量这一点。在硅 酸盐水泥中 L.S.F的含量应在 0.66到 1.02，越高，接近于极限值，越好。在孰料 中如果 L.S.F 的含量接近于 1.0，熟料就很难完全燃烧，特别是对于印度水泥工 业中这种类型的可燃煤，最好保持在 0.9 左右。

　SiO2/R2O3 这个因素是熟料中衡 量的通量，越低（接近于极限值） ，越容易燃烧。含量保持在 2.0在 3.0之间；经 过讨论发现在熟料中 2.41是一个理想值。这样 MgO 必然存在于水泥混合原料中。

　一般 MgO 不和水泥化合物结合在一起，但是起到熔合作用。另一方面，有个不 好的影响，在超高温下燃烧熟料中的镁石晶体时 MgO 难以形成；在过去几年里 这些方镁石晶体水合物在水化时很慢。因此熟料中 MgO 如果超过规范中最大值 时，水化将不完全。

　所以在印度硅酸盐水泥规范中， MgO 的最大含量限制在 6%。

　以 Na2O、K2O 和 SO3 形式存在的碱在熟料中小于 1%。在一些水泥混合原料中 很少存在 P2O5 n2O3、氯化物和氟化物。

　对于硅酸盐水泥的化学成分已经做了简要的讨论。

　被认为是， 硅酸盐水泥本 质上是由不同比例的硅酸三钙、 硅酸二钙、 铝酸三钙和磷酸三钙组成的； 再添加 一些石膏来控制凝结时间；增加水使得化合物的水化提供水泥凝结和硬化的性 能。这些化学反应包括水泥的凝结和硬化是非常复杂的， 有些反应很快， 有些很 慢。各种类型的硅酸盐水泥和混合水泥的基本原则（总而言之）是“形成的不可 逆的凝胶体和悬浮在液相上的凝结的细小固相形成了两种不同的网络结构， 凝固 和结晶，以及两个结晶凝结在一起形成网络结构。

　” 这种网络的一个特点是， 他 们表现出触变性，或者是粘度的变化，这种变化不是因为时间或者是温度的变化。

　在水泥中加水， 作用在水泥颗粒上， 形成水化硅酸钙超饱和水合物凝胶， 像 大量的微小晶体沉淀。

　水通过形成的表面膜进入水泥颗粒的核心， 水化率一开始 很快，后来逐渐慢下来。没有水化的水泥和水首先形成塑性体，接着，由水化硅 酸钙组成的细小晶体颗粒的凝胶和由水化钙质、 水化铝酸钙和由硫铝酸钙同时形 成的大于胶体尺寸的结晶产物。接着还有部分脱水产品和一些稳定形成的凝胶。

　从塑性体到同时生成的晶体产物的变化发生在水泥浆体的凝结过程中， 水泥 浆体的硬化归功于凝胶中大量增长的晶体。

　因此，水泥浆体的凝结变化是由于晶 体凝结的网络结构或多或少的触变性质的发展； 水泥浆体的硬化变化是由于更加 强大的不可逆转的晶体结构的发展。

　在水泥凝结和硬化过程中，添加的石膏作为一种缓凝剂起着很重要的作用。

　代表着通过形成钙磺胺 -铝酸盐来制造各种不同的石灰水泥化合物的速度。

　因此， 凝结和硬化的水泥本质上是由水化硅酸钙浆体和铝酸三钙浆体组成的， 这两个不 同组成的浆体都取决于水泥的化学成分。

　在硬化的水泥中或多或少地存在这些化 合物，使得水泥浆有不同的性质，如中等强度，较高的早期强度，较高的终极强 度，低的水化热，更好的抗硫酸性能等等。在以上几行中，硅酸盐水泥和混合水 泥浆体的凝结和硬化的原则已经简单明了地阐述了。

　进一步的细节需要对水泥浆 体水化的更深层的研究。