碱矿渣水泥固化高放射性废液的研究

水泥固化高放射性废液的机理有三个方面：机械固化、吸附固化和化学固化（固溶固化）。从这三个方面出发,通过对碱矿渣水泥固化高放废液的研究,并结合国内外水泥固化高放废液的研究现状,初步分析和阐述了碱矿渣水泥固化高放废液的理论依据,指出碱矿渣水泥比硅酸盐水泥更适用于高放废液的固化。     

硅酸盐水泥固化/稳定化剩余污泥探索研究

以普通硅酸盐水泥固化污水处理厂剩余污泥为建筑材料,探索了剩余污泥资源化处置方法。将剩余污泥与水泥按照一定配比混合均匀,置于标准养护箱中养护3～28 d,以污泥-水泥固结体无侧限抗压强度(R_C)和总有机物质量分数(TOC)为评价指标。结果表明,当污泥与水泥质量比(R_m)为0.63、液固质量比(R_l/s)为0.31时,固结体28 d的R_C约为6.9 MPa,该强度不满足非烧结砖最低强度要求,但满足剩余污泥填埋要求;污泥-水泥固结体浸出液中有机物质量分数(TOC_l)较固结体中初始有机物质量分数(TOC₀)减少约86%。硅酸盐水泥固化剩余污泥可以有效地将剩余污泥中有机物稳定在固结体中,对其进行填埋处理可有效抑制剩余污泥对土壤的二次污染。     

渗滤液浸泡对碱渣固化污泥长期性能的影响

以碱渣—矿渣—生石灰固化污泥用作填埋场临时覆盖材料为背景,开展不同渗滤液浓度、浸泡时间和碱渣掺量条件下固化污泥性质的研究,探讨渗滤液浸泡对固化污泥长期性能的影响规律及微观机理。结果表明：固化污泥在渗滤液中长期浸泡时,生成钙钒石和水化硅酸钙等物质,试样强度随浸泡时间的增加而增大,固化污泥有较好的耐久性;但当碱渣掺量60%的试样浸泡210 d时,试样中生成大量的碳酸钙和不同尺寸的钙钒石,结构变得疏松,试样出现裂隙,强度大幅降低,低于垃圾填埋场临时覆盖材料强度要求,碱渣掺量过多对固化污泥的长期强度不利。渗滤液对固化污泥有一定的侵蚀性,固化污泥强度随渗滤液浓度的增大而降低。固化污泥具有结构性,不同渗滤液浓度和浸泡时间下固化污泥结构屈服应力变化与强度变化规律基本一致。在渗滤液长期浸泡过程中,碱渣—矿渣—生石灰对污泥和渗滤液中的铬、铜、铅、砷等污染物可起到稳定作用。     

海洋疏浚泥固化处理土基本力学性质研究

针对海洋疏浚泥传统抛填中产生的环境污染问题，提出将疏浚泥进行固化处理后转化为土材料进行使用的方法 ，并对疏浚泥固化后作为土材料的基本力学性质进行了试验.通过对大亚湾海洋疏浚泥不同水泥掺加量和龄期的各种试验 ，得到了固化土的无侧限抗压强度与水泥掺加量之间的线性关系，明确了固化土破坏应变随水泥掺加量呈乘幂减小的规 律，并对固化系数和最小水泥掺加量等参数的物理意义进行了分析，给出了简单的推求公式.结果表明，淤泥经固化处理 后能够满足作为普通填方土材料的需要，而且可以根据工程的需要设计出经济合理的固化方法，为实际工程的应用奠定 了基础.     

不同含铝材料对水泥石固化氯离子能力的影响

采用化学分析、XRD、SEM等方法研究了掺加不同含铝材料(矿渣、偏高岭土、高铝水泥)水泥石对氯离子固化能力的影响,同时又测定了其强度.研究结果表明：随着含铝材料掺量的增加,水泥石中弗里德尔盐(Friedel’s salt)的含量显著增加;矿渣、偏高岭土、高铝水泥掺量分别为50%,25%,20%时,固化率达到最大值;SO₄^2-会显著降低水泥石对氯离子的固化率;含铝材料掺入合适的量对水泥石的强度有促进作用,并确定偏高岭土、高铝水泥的最佳掺量分别为20%、10%.     

水泥对铬渣无害化处理及其固化体浸出毒性的研究

对水泥作胶凝材料固化铬渣进行了研究。首先硫酸亚铁溶液与铬渣搅拌，然后再加入粉煤灰，水泥，矿渣等，部分还原的六谷铬转换为三价铬被固定在水泥基质中。研究结果表明，这样得到的固化体六价铬浸出毒性低于国家标准，抗压强度可达30MPa以上，能用于建材。本实验还考虑日晒，浸出时间和固化体粒度等因素对固化体浸出毒性的影响。     

模拟高盐、高碱中低放废液水泥固化体的浸出性能

针对高盐、高碱中低水平放射性废液的特性,研究了掺合料的种类、掺量对水泥固化体Sr^2＋,Cs^＋的浸出性能的影响。结果表明,矿渣和粉煤灰同时掺入,对降低Sr^2＋的浸出率较为明显;沸石、凹凸棒石的掺入,对降低Cs^＋的浸出率显著。当硅酸盐水泥：矿渣：粉煤灰：沸石：凹凸棒石=4：2：2：1：1时,42dCs^＋的累积浸出率仅为未含掺合料时的15．2％。浸出液的电导率表明,矿渣、粉煤灰、沸石、凹凸棒石的掺入对废液中的可溶性盐固化有利。用掺有矿渣、粉煤灰、沸石、凹凸棒石的硅酸盐水泥固化模拟高盐、高碱中低水平放射性废液时,固化体中Sr^2＋,Cs^＋的浸出率可以满足GB14569．1—2011的要求。     

Sr、Cs在碱矿渣-粘土复合水泥水化物粉体中的吸附行为

水泥的水化物对核索离子吸附性能将影响水泥固化体对核索离子固化性能。应用静态吸附法研究碱矿渣一粘土复合水泥（AASCM）水化物粉体对模拟放射性核素Sr、Cs的吸附性能及其影响因素，并和硅酸盐水泥（Pc）、铝酸盐水泥（AC）、矿渣硅酸盐水泥（PSC）、碱矿渣水泥（AASC）进行对比。结果表明，实验条件下，母液浓度提高，AASCM水化物粉体对Sr、Cs的吸附量增大，吸附比减小；温度升高，吸附平衡时间缩短，吸附量和吸附比下降。Cs在AASCM粉体中的吸附在一定的浓度范围内服从Freudlich吸附等温方程；AASCM水化物粉体与Sa^2＋的作用在母液浓度较大时存在吸附和沉淀双重机制，与Cs^＋的作用则主要是吸附机制；AASCM水化物粉体较PC、AC、PSC、AASC具有更强的吸附能力。     

基于骨架构建污泥固化体收缩与开裂特性的研究

针对传统污泥固化方法中固化污泥体易收缩开裂等问题,基于骨架构造原理,用煤矸石作为骨料,加入水泥、生石灰、粉煤灰等固化材料,按照不同配比对污泥进行一系列的固化实验。考察了在28 d养护龄期污泥固化结实体的开裂与收缩特性。研究表明加入煤矸石作为骨料能有效地抑制固化污泥的收缩与开裂,生石灰能抑制开裂,粉煤灰对污泥固化体的收缩开裂特性影响较小。     

低放高盐模拟核废液水泥固化体中无机盐的赋存状态研究

采用水泥固化法对模拟核废液（主要核素为137^Cs,90^Sr,主要含钠盐（质量分数〉15%））进行固化并在普通硅酸盐水泥中掺入矿渣、粉煤灰、沸石及凹凸棒土掺合料,以观察掺合料对固化体中无机盐赋存状态的影响。采用SEM,XRD及FT-IR对核废物固化基材的微观结构、物相及产物组成进行了表征与分析。结果表明：引入矿物掺合料能降低水泥固化体中无机盐的流失量,尤其掺入矿粉使无机盐的流失量降至82.5%;废液中大部分无机盐以沉淀或持留在水泥水化产物中的形式存在于硬化水泥石的孔隙中;矿物掺合料引入大量SiO2,使得水泥石中Ca（OH）2相基本消失,C-S-H凝胶的含量大幅度提高,部分Na^＋进入C-S-H凝胶的层间位置从而提高盐的固容量。     

Resource utilization of slag from desulphurization and slag skimming: A comprehensive recycling process of all components

In order to make the slag from desulphurization and slag skimming (SDSS) to be comprehensively recycled and utilized, a combined process of beneficiation and building materials preparation was proposed to recover iron from SDSS, meanwhile to apply the remaining slag tailings as cement admixture. From this process, three iron-rich products were recovered in stages by clean gravity - magnetic separation, slag tailings were left. Slag powder was prepared by ultrafine grinding of slag tailings. The stability, setting time and cement mortar strength of the slag tailings cements (STC) which were mixed with Portland cement and slag powder were studied respectively. The results showed that a proper overall performance still could be obtained at the slag powder content of 30%. Chemical composition analysis, X-ray diffraction (XRD) analysis, metallographic microscope and scanning electron microscope (SEM) analysis were employed to assess the characteristics of the SDSS and the products obtained from the whole process. The results indicated that the three iron-rich products could be used as a raw material for steelmaking and ironmaking and the relatively large amount of calcium silicate (C₂S) and tricalcium silicate (C₃S) in the slag tailings make the addition of slag powder into the Portland cement feasible.     

基于矿渣水泥3d强度推测28d强度的研究

阐述矿渣硅酸盐水泥的强度增长是受水泥熟料的组成、结构、矿渣质量与掺量等因素的影响.并论述了不同企业的矿渣硅酸盐水泥的强度发展过程不尽相同,但是都有相同的增长规律.笔者利用辽宁地区矿渣硅酸盐水泥3d强度推测28d强度,经统计分析与评价,建立的推测模型可以利用地方水泥的特点,较好地评价水泥的28d强度,并应用于实际工程,对科学利用水泥活性在保证工程质量的前提下降低成本十分有益.     

Strength of limestone-based non-calcined cement and its properties

A new type of cement was prepared with ground limestone powder, blastfurnace slag, steel slag and gypsum without calcination. The fraction of ground limestone powder in the cement was as high as 40 wt%–60 wt% without Portland clinker. All of its physical properties can meet the requirements of masonry cement standards. The impact of limestone content on physical properties of the cement and determined its impact on law was investigated. The steel slag can excit the aquation activity of this cement effectively, and the influence of its quantity on the strength of the materials was studied, which shows that the optimum quantity of mixing is 10%. By way of changing the different content of the lime stone by quartzy sample, the law of the compression strength and the PH value was determined, confirming that the lime stone can promote the early aquation of the slag and improve the early strength. The main hydration product of this cement is calcium aluminate hydrate, ettringite and calcium silicate hydrate, as indicated by XRD and SEM analysis.     

海水侵蚀环境下混凝土强度的研究

采用普通硅酸盐水泥和矿渣硅酸盐水泥 ,分别配制了水灰比在 0 .4 5～ 0 .6 0范围内的混凝土试件 ,采用加速腐蚀试验 ,研究了在海水腐蚀后 ,其强度随时间变化的规律及原因 ,并为试件损伤状态定量化解析提供了试验数据。研究结果表明 ,在相同的试验条件下 ,矿渣硅酸盐水泥混凝土抗海水侵蚀性优于普通硅酸盐水泥混凝土 ;混凝土试件的抗蚀系数为 0 .8时与美国ASTM标准规定的强度损失 2 5 %的界限值相吻合     

水泥矿渣稳定黑土的试验研究

采用水泥、矿渣微粉和石灰进行稳定黑土的试验研究。结果发现，在同等胶凝材料掺量下，采用一定配比的水泥和矿渣微粉，其稳定效果优于普通硅酸盐水泥；采用石灰等量替代部分水泥则导致稳定土的强度下降。虽然水泥矿渣稳定黑土比较经济，但其稳定机理和普通适用性值得进一步深入研究。     

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

The composition and structure of the interfacial zone be-tween aggregate and portland slag cement paste as well as the orienta-tion coefficient of portlandite(I_CH) have been studied by means ofXRD and SEM. The results show that the main components in the in-terfacial zone are C-S-H gel, portlandite and AFt as well as unhy-drated clinder particles. Compared with portland cement, there aremore C-S-H gel and less portlandite in the zone and the portlanditecrystallizes badly with lower I_CH in a narrower region. Afer adding5.0% silica fume to the cement, the orientation of portlandite in thezone disappears; afer 90d, the bond strength between # 425 portlandslag cement paste and aggregate approximately attains that between #525 portland ciment paste and aggregate.     

Effect of Fine Steel Slag Powder on the Early Hydration Process of Portland Cement

1 IntroductionSteel slag is the waste residue of fluxing mineralsused in the process of steel producing. Its dischargeamount is about 10 % of the production of steel . Steelslag hasn’t been utilized widely and effectively in a longperiod of time[1]. Hundreds of million tons of steel slagare deposited,andthe amount is still increasing withtensof milliontons every year .The deposited steel slag occu-pies great amounts of farmlands and induces serious en-vironment problems . The main chemical c…     

PERFORMANCE OF PULVERIZED SLAG SUBSTITUTED CEMENT

The Portland cement is equivalently substituted by slag micropowders with various specific areas. The workability, activity and acid-corrosion resistance of the slag-substituted cements are investigated, the activation of gypsum is discussed, also the porosity and pore distribution of mortars of the slag micropowders cement are determined by mercury intrusion porosimetry.     

The chloride permeability of persulphated phosphogypsum-slag cement concrete

The chloride permeability and microstructure of persulphated phosphogypsum-slag cement concrete (PPSCC), the Portland slag cement concrete (PSCC) and ordinary Portland cement concrete (OPCC) were investigated comparatively. Some test methods were used to evaluate the chloride permeability and explain the relationship between the permeability and microstructure of concrete. The results show that the resistance to chloride penetration in PPSCC is significantly better than that in OPCC, the reasons are as follows: 1) the slag in PPSCC is activated by clinker (alkali activation) and phosphogypsum (sulfate activation), forming more low Ca/Si C-S-H gel and gel pores below 10 nm than OPCC, improving the resistance to chloride penetration; 2) the hydration products of PPSCC have a much stronger binding capacity for chloride ions; and 3) in the same mix proportion, PPSCC has a better workability without large crystals calcium hydroxide in the hydration products, the interfacial transition zone (ITZ) is smoother and denser, which can cut off the communicating pores between the pastes and aggregates.     

The Properties of Cement Mortars Modified by Emulsified Epoxy and Micro-fine Slag

1　IntroductionDuetotheirexcellentworkability ,highcompressiveandtensilestrength ,goodimpermeability ,highcorrosion-resistingperformancesagainstacid ,alkaliandsalt,thecement basedmaterialsmodifiedbypolymershaveratherwideapplicationfields .Amongthevariouspolymers ,epoxyresinhasmanyadvantages :(1)Highbondingstrength .Fattygrouphydroxyl,etherandepoxy based ,areinvolvedinthemolecularstructureofepoxyresin .Thepolaritiesofhydroxylandethercauseelectromagnetismorchemicaladsorptionbetweentheepoxyresin…