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yqp36 加水 盘式成球机 设计

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YQP36预加水盘式成球机设计,yqp36,加水,盘式成球机,设计

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FeasibilitystudyrequirementsforanewcementplantR.Hogg,DFrameandM.E.Asim,WSAtkinsConsultants,UK,discussthetheoryandpracticeofundertakinglargecementplantprojects.FORSPANISHANDFRENCHVERSIONSPLEASEREFERTOTHESPECIALTRANSLATEDSECTIONATTHEBACKOFTHEISSUEIntroductionThedecisiontostarttheconstructionofanentirelynewcementplantfacility,oramajorcapacityextensionatanexistingcementworks,shouldalwaysbebasedonadetailedtechno-economicfeasibilitystudy.Suchastudywillindicatetothepromotertheviabilityofthebusinessintermsofthebesttechnicalsolution,theoverallcapitalandoperatingcasts,themagnitudeoftheoperationintermsofproductionandworkforceneeded,andthereturnonhisinvestmentoveraperiodoftime.Atypicalfeasibilitystudydealswiththefollowingissues:Marketingstudy.Rawmaterialsproving.Sitestudies.Conceptualengineeringandprocessdesign.Analysisofalternatives.Projectcostincludinginfrastructure.Projectschedule.Investmentanalysis,riskassessment,developmentoffinancialstructures.Projectfinance.Discussionwithfinancinginstitutions.Whilstanyfeasibilitystudymustincludetechnicalaspects,itisimportanttorealizethefullimplicationsofmarketingresearchandaccuratefinancialprojections.Pro-feasibilitystudyInordertominimizefrontendexpenditureandtoquicklyobtainafirmindicationofthelikelyprojectviability,apre-feasibilitystudyisperformed.Thepre-feasibilitystudyiscarriedoutatlowcost,butinsufficientdetailtoshowwhetherafullfeasibilitystudyisjustified.Thepre-feasibilitystudywillexaminethemarketplace,therawmaterials,capitalandoperatingcosts,anddevelopabusinessplantoshowthelikelyreturnsontheinvestment,andidentifytherisksandscaleofoperationinvolved.Typicallythisexercisewilltakefourtosixweekstocomplete,commencingwithasitevisit.However,thestudyislargelyperformedbydeskresearchandreferencetothein-housedatebase.Thesitevisitisusedtodeterminethesuitabilityofrawmaterialsforcementmanufacture,localbuildingandcivilengineeringcosts,costoflandandpeculiaritiesoftheparticularsitelocation,andlocalcostofconsumablesrequiredintheoperationoftheplant.Thedeskresearchconcentratesuponcurrentplantandmachinerycosts,financialandmarketingconsiderationsandpreliminaryplantsizinganddeterminationoftheprocessroute.Intheeventofthepre-feasibilitystudyshowingaclearindicationthatitisworthwhiletoproceedwiththeproject,thenafullfeasibilitystudycanbeinitiated.FullfeasibilitystudyMarketresearchTheobjectiveofthemarketstudyistoestablishthedemandforthevarioustypesofcementinthecontextoftheregionormarketareaoftheproposedplant.Thestudyseekstoestablishthecurrentandforecastcementusageovera5-7yearperiod.Theforecastisthenusedtogetherwiththeindicatedsellingpricestogeneratethelikelyrevenuestreamfortheproposedoperation.Theconsultantmusthaveconsiderableexperienceintheglobalcementindustryandbeabletoapproachafeasibilitystudywithanexcellentknowledgeofprevailingmarketconditionsandlikelytrends.Eachindividualcompanyandmarketdoes,however,presentauniquesetofcircumstanceswhichmustbefullyunderstood.Thenormalapproachadoptedisfirsttostudythecompanyandidentifyitsstrengthsandweaknesses,strategicdirectionandmotivation.Thisisessentialinprovidinganimmediatepictureofthecompanyslikelysuccessinachievingitsaims.Thesecondstageofthemarketingsurvey,deskresearch,putstheinitialdiscussionsintocontextbyexaminingawiderangeofpublisheddatarelevanttotheindustry.Sourcesofpublisheddataarecollatedandcomparedbyateamofresearchersandconsultantsinanoperationtosubstantiateknowntrendsanduncovernewinformation.Itisnotsufficienttorelyoninformationseveralmonthsold,andwithoutaninternationalperspective,trendsincementproductionanddemandarefrequentlymisleading.Collectingpublisheddataisanon-goingprocess,buthavingestablishedabackgroundtothestudy,informationshould,wherepossible,beverifiedusingindependentsourceswithfirsthandaccountsoftheindustryanditsoutlook.Companies,governmentorganisationsandotherindustryassociationsareoftenwillingtoprovidetheirownassessmentlfmarkets,butcareneedstobetakennottocompromiseanypartypreparedtogiveitsview.Armedwithacomprehensiveselectionofpublisheddataandindustryopinion,thejoboftheconsultantatthisstageistoaccuratelydefinenotonlythemarketsizeforaparticularproduct,butthelikelychangeinthatmarket.Suchchangesareoftenpredictedbyhistoricrelationshipsbetween,forinstanceGDPandoverallconstructionactivity;economicgrowthandhousingstartsofcementconsumptionandpopulationsize.Figure1illustratesthispoint.Withouttakingintoaccountsubjectiveopinionandrecognizingchanginguserrequirementsfordifferentcementtypes,suchforecastscanbeflawed.Analysisofsuchfactorsisparticularlyimportantinlesserdevelopedcountrieswhereimpressivegrowthratescanchangethebalanceofconstructionactivityoverremarkablyshortperiodsoftime.Othereconomicinformationlikelytohaveabearingonthemarketaregovernmenttariffs,importdutiesandsectorsubsidies.Eveninfreemarketareas,manyaspectsofeconomiesareregardedasbeingofstrategicimportanceandgovernmentsfrequentlystrivetopreservenationalinterestswhereverpossiblebyfixingpricesofimposingimporttariffs.Shouldimporttariffsberelaxedofpricesallowedtomoveinlinewithsupplyanddemand,therewillbeanappreciablechangeinthemarketconditions.Nationalcompanies,forinstance,mightsuddenlyfindthemselvesuncompetitive.Withcheaperimports,thebalancebetweencementgrindingandclinkerproductionrequirementscouldchangequitedramatically.Itwouldbeuptthegovernmenttoaccommodatethesechanges,butoneoftheprincipletasksoftheconsultantistoanticipatethem.Thislastpointhighlightswhatisperhapsthesinglemostimportantyetdifficulttodetermineaspectofamarketstudy:competitorreaction.Knowingofothersinvestmentplans,governmentlicensing,likelydatesofcompletion,principlecontractorsinvolvedanddistributionpartnersisdifficultandtimeconsuming,butitisnotenough.Competitorsarenotjustnationalsofthosewhohavehistoricallysoldtheirproductthroughthesamepredictablechannelsofdistribution.Thereareanincreasingnumberofcompanieswhowouldliketoreducedependenceonsuppliersbyverticallyintegratingtheiroperations.Thiscouldentailbuildingtheirownplantordevelopingtheirowndeepwaterterminaltoimportcementdirectly.Othersmightdecidetodiversifyintoselling,forexample,readymissedconcrete.Somelargeusersmightbeonvergeofenteringintolongtermagreementswithonecompanyorlookingtobuyformfurtherafield.Thecombinationsarenumerousbutitisuptothecompanyinvestinginexpensiveplantandmachinerytounderstanditscustomersandconvincebothitselfandtheinvestorsthatitreallydoeshavethebestviewofthemarket.RawmaterialsprovingThevolumeandqualityoftherawmaterialdepositshavetobeestablishedwithaccuracy.AwiderangingsearchforrawmaterialsmaystartwithdeskresearchandconsultationwithNationalGeologicalSurveydataandavailablegeologicalmapping.Thesearchwillincludeexaminationofaerialphotographyrecordsandsatelliteimagerye.g.LandsatorSPOT.Thedeskresearchisfollowedbuysitevisitstotheproposedlocationbygeologistswhotakethestudyastepforwardbymakingon-siteexaminationsofpreviouslyidentifiedgeologicalhorizonsandoutcrops.Thefirstsamplesaretakenbychannelingfrompromisingoutcrops,roadcuttings,recentexcavationsorfrompurposeexcavatedtestpits.Fieldtestingofthesamplesisrequiredtoprovideaninitialindicationofthecalciumcarbonate,silica,aluminaandironcontentofthedeposit.Thetestingissimple,rapidandeconomicalandthegeologistcanadjustthefieldinvestigationsandmaximizetherecoveryofusefulinformation.Themostpromisingsamplesarechemicallyanalysedintestinglaboratoriesandwhensufficientdatahasbeenobtainedintermsofchemicalquality,andtheprobablevolumeestablished,adecisiontomountafulldrillingcampaigncanbemade.Theprimaryrawmaterialorlimestone,iscoredrilledandcarefulrecordsofthegeologicalprogressionismadeasthecoresarerecovered,recordedandlaidsequentiallyinthecoreboxes,(Figure2).Individualandcompositesamplesaretakenfromthecoresandsenttolaboratoriesexperiencedinthetestingofcementrawmaterials.Inordertominimizedrillingcostsisessentialthattheinitialresultsofthefirstboreholeareanalysedrapidlyandtheresultsknowninordertomakefurtherdecisionsonlocation,angleanddirectionofsubsequentboreholes.Theinformationobtainedfromthechemicalanalysesandthegeologicalrecordderivedfromthecoresinthenusedtoestablishthegeologicalstructureandthevolumeofthedeposit.Theoptimumquarrydevelopmentsarethendeveloped.Thesecondaryrawmaterials,claysorshales,maybeprovenbymeansofaugerdrillingofbytestpitexcavationusingmobilehydraulicexcavatorsorinsomecasesbyhandexcavation.Thesematerialsaresimilarlyrecordedandchemicallyanalysedasforthelimestones.Usingthechemicalanalysisoftherawmaterial,computerizedrawmixdesignscanbecarriedout.Thein-houseprogramusedhasseveralfacilitieswhichcanbecalledupon.Firstly,allthenecessarystandardequationswhichmustbesatisfiedforlimesaturation,silicaratio,aluminaratio,hydraulicmodulus,etc.,arebuiltintotheprogram.Secondly,themixdesigncanberefinedbyadjustingthecompoundcompositionandobservingtheeffectuponthestandardratios.Finally,costfactorscanbeaddedtotherawmaterialstoobtaintheoptimumrawmixwhichminimizesthemostexpensiverawmaterials,butsatisfiestheabovecriteria.ProcessdesignTheoptimumprocessrouteforaspecificplantisdependentuponanumberoffactorsincludingthephysicalandchemicalnatureoftherawmaterialdeposits.Theselectionofplantandmachineryismadebasedonthefollowingfactors”Dispositionoftherawmaterialdeposits.Moisturecontentandotherphysicalpropertiesoftherawmaterials.Levelofundesirablechemicalelements.Mineralogy(particularlythecontentandsizeofsilica).Abrasiveness,grindabilityandtheburnabilityoftherawmaterials.Fueltypesandrelativecosts.Environmentalprotectionrequirements.Electricalpoweravailability,costandenergyefficiencyrequirements.Sitetopographyandcongstraints.Marketconstraints.Labourandmaintenanceconstraints.Thedispositionoftherawmaterialsintermsofdipandstrikeandphysicallocationdictatehowtheprimaryandsecondaryrawmaterialquarriesareopenedup,howtheyaretobeworkedandhowtheaccessroadsaretobedeveloped.Thegeologicalmethodofdepositionandhardnessoftherawmaterialswillalsodeterminehowthequarryistobeplannedandthemethodsofextractiondetermined.Themoisturecontentoftherawmaterialsandthechangeintheircharacteristicsasthemoisturecontentaltershasanimportanteffectuponthechoiceoftheprimarycrusherandstoragesystems.Themoisturecontenthasevengreaterimplicationswhenconsideringtherawmillingsystemtobeproposedinconjunctionwiththeoptimumtemperatureofpreheaterexitgas.Abalancehastobestruckbetweentherequirementsofthekilnsystem,thenumberofcyclonestagesthatcanbeused,andtheheatrequirementsoftherawmillforrawmaterialsdrying.Thelevelofundesirablechemicalelementsintherawmaterials,suchaspotassium,sodium,magnesia,chloridesandsulfurrequirescarefulconsiderationintheselectionofthetypeofkilnsystem.Thevaryinglevelsofimpurityelementsinconjunctionwiththesulfurintherawmaterialandpossibleadditionalsulfurintakefromthekilnfuel,leadtothenecessarydecisionstobemaderelatingtotheacceptanceandsizingofabypasssystem.Themineralogycanvarygreatlyamongrawmaterialsindifferentcountries.Themethodofdepositionandtheoccurrenceofthechemicalelementsineachoftherawmaterialscanhaveamarkedeffectonthecharacteristicsofcombinationinthekilnburningprocess.Notablythisleadstovariationsinkilnfuelconditions.Predictionsuponhowtheraw-materialswillbehavewhencombinedinthenecessaryproportionstoobtainacommercialcement,arebaseduponlaboratoryburningandgrindingtestsconductedaspartofthefeasibilitystudy.Energyandfuelusagearetwokeymattershighontheagendaofallpotentialandexistingcementplantoperators.Thecementindustryhasalwaysbeenveryconsciousofmakingthemaximumuseofheatenergy,andtothisendheattransferfromthekilngasestotherawmaterials,offromthehotclinkertothecombustionair,hasalwaysbeenutilized.Todaymorethanevertheefficientuseofenergyandfuelissoughtaffairandarangeofplantandequipmentsavailableforconsideration.Technicaleconomyofscaleisalsoanimportantfactorandwherethemarketjustifylargecapacityplant,correspondwithreductionsinthecostofproductsareachieved.Energyconsumptionisbereducedthroughtheuseofroll-millingsystemsforrawmealinplantoftubemills,highefficiencyseparatorsinboththerawmillingandcementmillingdepartments,lowpressuredropcyclonesinthepreheateroftheburningprocess,andbythepreheaterofhighpressuregrindingrolls,andrecentintroductionofthehorizontalrollermill,theso-calledHoromill.TheselectionoftheoptimumplanningprocessesensuresthattheKWh/helectricalpowerconsumptionminimised.Fuelconsumptionisreducedtheintroductionofefficientcyclonesconstructionwithheatresistanttubesandanincreaseinthenumberofstagesofpreheatertomountmaximumuseofthehotgasesleavingfromthekiln.Fuelconsumptionisalsosiderableaffectedbythedesignationancillaryplantsuchasthekilnseparators,gasducting,kilnburner,flowcontrolvalvesandinstrumentation.Anotherrecentdevelopmentisthetransferofallthehotexhaustedgasesformtheclinkercoolerbackontotherawmill,thussavingontheheatrequiredfordryingtherawmaterial.Thisarrangementalsohastheacuteadvantageofreducingthecapitaloftheplantbytheeliminationofacipitatororotherclinkercoolercollectionsystemanditsassociatingequipment.1新型水泥生产工艺的可行性研究要求英国WSAtkins专家R.Hogg,DFrame和M.E.Asim讨论大型水泥设备工程的理论可行性。针对西班牙语和法语的版本请参考本杂志的后面特别翻译部分。杨闻达译引言开始建造一套完整的新型水泥生产工艺设备或在已有的水泥生产设备上进行主要设备生产能力的扩充改造，这些计划都应该在详细的技术经济分析的基础上实施。这样的研究涉及到采用最好的技术方案、总的成本和总的运营支出这些方面，同时也涉及到生产、所需的劳动力及在一定时间段内投资回收的运营规模，它能体现出工程较好的经济可行性。一项典型的可行性研究主要需解决以下问题：市场调查分析。生料的供给。厂址选定及设备的安装研究。工程及工艺的概念设计。互换性分析。包括基础设施的支出预算。工程时间表。投资分析，风险评估，财务结构的发展。项目费用。财务状况的讨论。所有的可行性研究报告必须包含技术方面的问题，它在解释市场研究与合理的资金规划之间的完整关系上是很重要的。预先可行性研究为了使所有的费用最低化，为了能很快地达到工程可行性的预定指标，预先可行性分析是必需的。预先可行性研究是在以很低费用支出的条件下完成的。当有充足的准备条件时它又能显示出完整可行性分析的公正性。预先可行性研究要调查市场、寻求原材料、筹2集资金和准备运营费用，从而拟订一份商业计划。这样就知道可能的投资回收、对风险的分析和所在的运营环境。典型的预先可行性研究过程从开始将需4到6周才能完成，而研究中的大多数工作都是在办公桌上参照内部的数据库来完成的。现场考察过程是根据水泥生产、本地建筑、民事工程费用支出、土地费用、特殊地方的独特性以及在当地工厂运营所要求的费用支出确定合适的生料。办公桌上的研究工作注重于现在工厂、机械设备、财务、对市场的考察及主要设备安置和工艺路线的确定。在预先可行性研究清楚地展现出这项工程是值得进行的后，完整的可行性研究才能开始。完整可行性研究市场调查市场研究的主观目的是满足在一定区域背景和工厂计划的市场范围内对各种水泥的需要。市场研究寻求满足现在以及预计在以后长达5到7年这段时间内的水泥使用需求。这样的预测与市场的指导价结合，形成在计划操控下可能的收入趋向。这方面的专家必须要有对全球水泥工业的相关认识，以及能对市场最新的状况和可能的发展趋势有所把握，这样才能进行可行性研究。各个公司和地区都是这样的，同时又体现了各自独特的背景，这样的背景却是必须要充分把握的。通常所运用的方法是首先研究公司和分析它的优势和劣势，战略性方向和动向。在证实公司为实现其目标制订的成功性很大的近期规划中，这方法是不可或缺的。所运用的方法的第二阶段是通过调查涉及工业大范围的公开数据，进行市场观察，现场研究，将原先的讨论实践到具体的背景下。公开数据是研究者和专家对已知的客观趋向进行分析和对未知的新信息进行推敲和比较所得出的。单单依靠几个月前的旧信息，且忽视在水泥生产方面的国际性观点、趋势是不够的，这样所得到的水泥需求也总是失去指导性的。收集那些公布的数据是一个持续的过程，但是是在确定调查研究的基地后的工作，并且已收集的信息应该通过第一手获得的工业资料和观点尽可能被证实。公司、政府组织和其他的工业协会总是希望提供他们自己的市场评估，并且需要注意不去妥协于任何被强加的观点，准备给出自己的见解。这个阶段中，在已经把握好那些广泛收集的公开数据和工业主张后，专家的工作3就是正确地定义特定产品所针对的市场，另外还有市场中可能的变化。这些变化总要靠具有历史意义的关系来预料的。例如，这些关系包括国民生产总值和所有建设活动的关系，经济增长和房屋建造的关系，或者是水泥消耗和人口数量的关系。图1说明了这一点。如不考虑那些客观意见和不认清水泥使用者对不同型号的水泥需求的变化，这样的预测是错误的。对这些方面的分析在一些非发达国家是尤其重要的。在这些非发达国家，不乐观的生长率在显著的短时间内会改变建设活动的平衡性。另外可能会给市场带来负担的商业信息是收费表、进口关税和部分的津贴。即使是在自由经济时期，经济的很多方面都与战略的重要性，以及政府为维持国内汇率总会通过确定一定的价格表，或提高进口关税的措施有关。如果取消进口关税或者价格只依据供求关系来变化，这在市场条件下将是很重大的变化；譬如，国内公司会突然发现他们自己毫无竞争能力。随着进口商品的价格越来越低，水泥粉磨和熟料的需求平衡可能会有显著变化，这取决于政府所采纳的政策的变化，而专家的主要工作之一就是预计它们。最后要强调的一点是竞争者的反应。它也许是在决定市场研究的各方面问题中的唯一并且是最重要的难题。要想得知其他的投资计划、政府许可、可能的竞争数据、在竞争者中主要的竞争者和合作伙伴，这样的过程是很困难也是很费时的，同时它也总是远远不够的。竞争者不单单是国内的或者是长期以来以同样的可预测的销售途径来销售他们的产品的，现在越来越多的公司希望靠纵向的统一他们的运营来减少对供求方的依赖性。这将能帮助建造他们自己的工厂或发展他们自己的用于直接进口水泥的深水港。其他的公司也许会决定转变成卖方，例如，卖罐装混凝土。某些大客户也许会和这样的一个公司签订长期合作协约或寻求更大更广远的市场去买进水泥。研究的组合方式有很多，这取决于公司在昂贵的厂房和机械设备投资的金额。这样的研究是为了了解投资所要针对的顾客，也是为投资者们确定这样的投资确实拥有一个最广阔的市场的。原材料的考证对于生料矿藏的储量和质量，我们必须对它们有很准确的认知。对原材料广范围的搜寻可以以研究台上的研究及借助国家地质勘探这本书的数据和使用的地质图谱为指导来开始。这样的搜寻将包括调查无线的照图记录和卫星图片，例如查看Landsat或SPOT卫星图片。4紧接着研究台上的工作是现场考察那些规划地点，这工作是由地质专家通过现场考察以往鉴定的地理水平线和岩石层，从而能深入地研究。第一步取样品工作。在可能有很好迹象的岩石层、山中开辟的道路、现在已有的开采进行引导性挖掘，或者在计划开采的测试点进行引导性钻孔。矿区的样品测试需要提供储存的氧化钙、硅、铝和铁含量原始指标。这样的测试是简单的、快捷的、经济的。地质专家能调整矿区调查工作和最大化地收集发现的有用信息。最有指望的样品收集工作是在测试实验室进行化学分析后，掌握了充足的化学质量的数据和已确定可能的数量时，决定开始完全开凿工作。主要的生料成分或者石灰石是钻孔所要的核心。对地质进展需要进行详细记录，如把核心开采出来、记录，并把它们分类放入核心箱内（图2）；从钻核中获得