THE FORMATION MECHANISM OF PORTLAND CEMENT CLINKER MINERALS IN RAPID BURNING

Cement clinker is burnt at the rapid heatingrate has the obvious effect of saving energy due tothe low burning temperature and short burning time.This kind of technique is being researched activelyin recent years,but the systemetical theoryinvestigation about the formation mechanism ofclinker minerals under this condition has not beenreported.In this paper,the formation mechanism ofportland cement clinker minerals in rapid burningwas studied by means of DTA,SEM,EPMA,XRDand other conventional testing methods by using aspecial burning equipment.     

EFFECT OF BURNING METHOD ON THE FORMING PROCESSES OF PORTLAND CEMENT CLINKER

The forming temperature of Clinker meltunderdifferent burning conditions has been studiedby appearance examination and thermal shrinkerdetermination, and the viscosity of melt has beendiscussed by studying the coordination number ofAl~(3 ) and Fe~(3 ) in cement clinker burned by differentmethod with x~- ray fluorescence analysis and Moss-bauer spectroscopy. The results show that the clin-ker melt under rapid burning may come into exis-tence at lower temperature and It's viscosity islower. So the forming processes of clinker may bedifferent at rapid burning from ordinary burning.They are probably an important factor to promote theformation of clinker burned at lower temperaturewith rapid burning method.     

MgO ACTS THE BURNING OF WHITE CEMENT CLINKER

In this paper,how and why MgO acts on theburning of white cement clinker and increases thewhiteness were found by means of common detectionand EPMA.It was shown that MgO is a kind ofeffective mineralizer and brightener.     

RESEARCH ON RELATION BETWEEN MELTING POINT OF CEMENT CLINKER AND HEATING RATE

The relation between the melting point of Portland cement raw meal and its heating rate have been studied. The raw meal was burnt at different heating rate ranging from 10-900℃/min by the following methods: (A) in electric resistance furnace; (B) in DTA-TG analyzer with infrared ray focused heating; (C) in high temperature microscope with electron stream heating.     

A STUDY ON THE KINETICS AND SOME MECHANISMS OF CEMENT CLINKER FORMATION

In this paper for saving energy two differentburning methods of cement clinker formation havebeen studied.One is the rapid burning method andthe other is ordinary burning method simulatingrotary kiln,and they are compared by the kineticpoint of view.The result reveals that theactivation energy of rapid burning is much lowerthan ordinary burning.For looking into the cause,the main raw material—lime stone was burnt bythe same two methods and the structure of productCaO has been detected.It can be found that themicrostructure of CaO produced by rapidburning is looser;lattices constants aregreater;crystal defects are more and particlesize is smaller than that produced by ordinaryburning.These cause the chemical reaction moreactive.So the activation energy of clinkerformation of rapid burning is much lower thanthat of the ordinary burning.     

钢渣彩色水泥熟料低温烧成及其性能研究

水泥窑中直接烧成的彩色熟料水泥具有成本低、色泽鲜艳、色彩稳定性好等特点.本文着重探讨了在能源紧张情况下,利用氟、硫复合矿化剂低温烧成钢渣彩色水泥熟料的可能性.通过 X 射线衍射、扫描电镜观察和红外光谱等近代测试分析技术及化学分析、常规物理力学试验方法对用水泥工业性优质原料配料和掺电炉还原钢渣配料高低温烧成彩色熟料的矿物组成、色彩情况、物理力学性能及其特性进行了分析研究.     

STUDY ON STRENGTH AND PETROGRAPHIC STRUCTURE OF CLINKER BY LOW-TEMPERATURE BURNING

In this paper,the strength and petrographicstructure of clinker by low-temperature burning are studied.The results show that both the calcining temperature of Ca-CO_3,and sintering temperature clinker decreases by 150℃com-pared with those in traditional rotary kiln,the rate of f-CaOin the clinker sintered at 1300℃ is 0.29%～2.81%,thestrength of the clinker is 62.5MPa with maxium 69.4MPa ata specific area of 2900～3400cm~2/g.The results also showthat the types of petrographic structure of the clinker can beclassified as:homogeneous structure,inlaid or edged struc-ture,stain-melting structure and porous strncture.The clinkersintered at 1300±15℃ temperature and with enough reten-tion period is mainly in homogeneous structure.     

ON THE DECOMPOSITION OF ALITE IN PORTLAND CEMENT CLINKER

The decom position speed and mechanism ofalite in Poriland cement clinker are stuc’ied by means of op-tical microscopy,EPMA,XRD and chemical analysis.Theresults show that alite in portland cement clinker decompos-es at the maximum speed when the temperature is at 1025～1175℃.It takes about 40 hours for the alite in clinkerburnt in the rotary kiln to completely decompose at 1175℃,and the 68 hours for the alite burnt in RSP-kiln.Thepresence of CaF2 or CaSO_4 greatly affects the decomposi-tion speed of alite.The former resists alire to decompose butthe latter accelerates is and enables alite to decompose com-pletely within 6 hours or less.     

STRUCTURE AND HYDRAULICITY OF C_2F FORMED BY RAPID BURNING

The structure and the hydraulicity of C_2Fformed by the rapid burnign have been studied with the helpof XRD,IR, Mossbauer spectra,the combined water and oth-er analytical means. The technique of the rapid burning canchange the crystal structure of C_2F.There exist more octahe-dra (Fe~3~ ),less covalent bonding and more crystal defects inthe structure of C_2F. It is important that the hydraulicity ofC_2F can be enhanced by means of the technique of the rapidburning.     

EFFECTS OF PARTICLE SHAPES ON THE KINETICS OF SOLID REACTIONS

In the paper,the effects of powder particleshapes on the kinetics of solid reaction (K. S. R) and errorscaused by the current methods based on spherical particlemodels have been studied. It has been found that particleshaeps have significant effects on kinetics of the solid reaction(K. S. R). However it has now not been involved in the pre-sent kinetic equations as a factor. The ball models used by thepresent kinetic equation have led to great errors not only in de-termination of the reaction constants but also in judgement ofreaction types. This is a problem that has not been much recog-nized and needs to be solved immediaitly.     

CORRELATION OF THE COMPONENTS OF PORTLAND CEMENT CLINKER AND SINTERING PROCESS BY MEANS OF XRD QUANTITATIVE ANALYSIS

In this paper,the cement clinkers fromvarious industrial kilns were investigated by a superposingpeaks method for X-ray quantitative analysis(XRQA)ofclinker minerals,the results show that the clinker mineralcontents measured by XRQA method better accord with thereality of clinkers made in different conditions than theo-retic contents calculated by Bouge formula do.The mea-sured contents of C_3S of clinkers manufactured in rotarykilns are higher than theoretically calculated values,where-as,the results of clinker manufactured in shaft kilns arecontrary to that.This is because in rotary kiln,the rawmeals are fully pre-heated and have high sintering temper-ature,the clinkers are well solid-solutioned and rapidlycooled,on the contrary,owing to the struetural defects,it iseasy to exist reduing atmosphere and lower temperature inshaft kiln,moreover the cooling rate is slower,all these canevidently lead to worse clinker quality.Adding CaF_2-Ca-SO_4 complex mineralizer can remarkably modify the sinter-ing situat     

不同金属离子对单增李斯特菌生物被膜形成的影响研究

为研究生物被膜态微生物的特性,以常见的食源性病原菌单核细胞增生性李斯特菌为研究对象,采用银染法、扫描电镜法观察其形成的生物被膜形貌,超声剥离生物被膜及平板计数法检测生物被膜生物量,苯酚-硫酸法测定李斯特菌生物被膜胞外多糖的含量.结果表明:单增李斯特菌可在玻璃材料表面形成生物被膜,Mn2+、Ca2+、Fe2+对其基本无影响,添加Cu2+离子可抑制单增李斯特菌生物被膜的形成及胞外多糖物质的分泌.     

福建魁岐花岗岩形成的物理化学条件

福建魁岐碱性花岗岩的深色矿物成分特点和物理化学实验资料表明,岩石是在较高温、低压、相对还原、富碱和缺水条件下,由岩浆结晶形成的。     

燃油锅炉的实用性分析

本文通过燃油锅炉在实际工程中的具体运用,与燃煤锅炉进行了技术经济、环境保护、工程造价等方面的综合比较。     

全脂豆奶粉在氧化过程中产生荧光物质的动力学研究

全脂豆奶粉储藏于37℃、50℃、60℃和70℃下,氧化的全脂豆奶粉的荧光光谱显示最大激发峰于350 nm处和最大发射峰于440 nm处.发射荧光的物质溶于氯仿甲醇(2∶1,V/V)有机溶液中,荧光强度随着储藏时间延长和温度的升高成比例的升高.氧化生成荧光的动力学方程是个零级,呈上升趋势,斜率遵循阿仑尼乌斯经验式,活化能在55~75 kJ/mol范围内.所得动力学方程用来预测全脂豆奶粉在不同时间和温度下氧化产生的荧光强度及其脂肪氧化程度.     

多组分共聚酯结晶动力学研究

本文用DSC技术探讨了多组分共聚酯与PET的结晶动力学.结果表明,它们的Avrami指数均为2左右,并且多组分共聚酯的结晶速率比PET略慢.     

含磷零膨胀LAS透明微晶玻璃的相转变动力学研究

以零膨胀Li2O-Al2O3-SiO2透明微晶玻璃为研究对象,采用示差扫描量热法（DSC）研究了无磷和含磷玻璃的析晶动力学和玻璃转变动力学行为．结果发现,引入少量的磷化物使得玻璃的析晶峰温度和玻璃转变温度降低,玻璃的析晶活化能和玻璃转变活化能增大,晶体生长指数n减小,使玻璃网络结构重排困难．     

水泥浆搅拌法在加固处理软土工程地基中的应用

采用水泥浆搅拌法对方便面厂调料车间进行软土地基加固处理.简述了深层实体复合地基受力模式的设计方法,对新、老设计规范的一些技术参数进行比较、分析,论证说明了现行规范的安全性能,指出用水泥浆搅拌法加固软土地基,是长期工程实践中行之有效的方法.     

佳县—子洲地区太原组砂体成因及对储层的影响

按砂体的沉积特征和成因,可将鄂尔多斯盆地东部佳县－－子洲地区的太原组砂体分为潮汐沟道砂体,河道砂体和潮下砂坝砂体三类,不同成因的砂体,在结构组分,构造,测井曲线和展布形态等方面均有较大的差异,这些特征又明显地影响后期成岩作用类型和强度,从而控制着储层的孔隙类型,物性,分布等特征,研究表明,最有利于储层形成 与演化的砂体为潮汐沟道砂体,高的成分和结构成熟度导致胶结作用较强,压实和溶解作用表现不明显,使砂体内保留有相对多的粒间孔和高岭石晶间孔,物性也较好;这类砂体多呈条带状分布于太2时的中,南部地区,该区块的太2段亦是今后重点勘探的区块,河道砂体和潮下砂坝砂体的沉积特征决定了它们的储集性能不及潮汐沟道砂体,且分布局限,属于较差的储集砂体类型。     

INVESTIGATIONS ON THE INTERFACIAL ZONE BETWEEN AGGREGATE AND PASTE OF PORTLAND CEMENT

The composition and structure of theinterfacial zone between aggregate and paste ofportland cement as well as the orientationcoefficient of portlandite (Icn) werepreliminarily studied by XRD and SEMmethods.The main products in the zone are C-S-H gel,portlandite,AFt and pores,micro-cracks as well as unhydrated portlandcement clinker particles.Potlandite not onlygrows well but exists in orientating forms,andnear the interface it exists in a state parallel tothe surface of aggregate by its(001)latticeplane.Icn rises with the increase of cementwater ratio(w/c)and the development of thecement hydration.The higher the w/c,themore the pores and micro-cracks in thezone,w/c bears an exact relation to the decreaseof bond strength.Icn is decreased when 5.0%silica fume is added to cement.Bond strengthsat early ages are reduced by adding 0.5% FDN(one kind of water-reducing admixture)due tothe retarded hydration of cement,but they willincrease continually and become greater than those of other samples after 28 days.