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。     

基于水膜厚度假设分析磨细高炉矿渣对水泥浆性能影响

为探索磨细高炉矿渣对水泥浆性能及其水膜厚度的影响,研究测量了30组不同水胶比、不同磨细高炉矿渣掺量的水泥–;矿渣复合浆体的流动性能、黏聚性和抗压强度.为探索浆体的流变性能控制机理,进一步测量了5组不同磨细高炉矿渣掺量水泥–;矿渣复合浆体的填充密度,并基于填充密度测量结果计算出各浆体试样配比的水膜厚度,探索水膜厚度对水泥–;矿渣复合浆体流变性能的影响.实验结果表明,适量磨细高炉矿渣的掺入能提高浆体的流动性能和抗压强度,黏聚性些许减弱,最优配比磨细高炉矿渣掺量为5%,此时水泥–;矿渣复合浆体综合性能最好.磨细高炉矿渣掺入能提高胶凝材料的填充密度,水膜厚度为流动性主要控制因素,水泥浆的流动性能随水膜厚度增大而增大.     

地聚物对固化焚烧飞灰的研究

垃圾焚烧处理技术产生的飞灰浓缩了重金属等一些高毒性当量的危险成分, 如果处理不当会 产生二次污染, 因此焚烧飞灰被认为是危险废物, 必须进行特殊处理.论文对地聚物固化垃圾焚烧 飞灰的工艺及养护条件进行了实验研究, 以抗压强度和重金属浸出质量浓度为效果表征量, 研究了 地聚物固化飞灰的合成配方.结果表明:氧化物配比为m(Na2O)∶m(SiO2)=0 .30 , m(SiO2)∶m (Al2O3)=4 .7 时, 飞灰掺量为40 %的固化体在养护7 天后抗压强度能达到31 .25 MPa , 固化体中 Pb , Zn ,Cu 和Cr 的浸出质量浓度分别达到0 .183 8 , 0 .023 1 , 0 .008 1 , 0 .367 9 mg/L .     

利用垃圾焚烧飞灰固化污染底泥的实验研究

为探讨利用垃圾焚烧飞灰代替水泥进行污染底泥固化的可行性,研究了不同配比的底泥、水泥、垃圾焚烧飞灰的固化体抗压强度及浸出毒性.结果表明：固化剂中用20%的垃圾焚烧飞灰替代10%的水泥配置的固化体7.d,其抗压强度可达0.24.MPa,重金属浸出浓度低于毒性标准,固化体可进入固废填埋场填埋处置.     

钙基地聚合物抗压强度预测与优化分析

以偏高岭土、高炉矿渣、水泥制备钙基地聚合物，基于响应面法分析了水泥掺量、碱掺量、水玻璃模数对钙基地聚合物抗压强度的影响规律。试验结果表明，利用响应面分析法可以确定多种因素作用下钙基地聚合物抗压强度最优值，进而可以据此对其抗压强度进行预测与优化分析。     

碱-偏高岭土-矿渣水合陶瓷力学性能研究

研究了水热条件、粒化高炉矿渣掺量对碱-偏高岭土-矿渣水合陶瓷（alkali—activated metakaolin slag hydroceramic，AKSHC）力学性能和孔结构的影响；测定了当矿渣掺量为20％时，AKSHC基材的耐酸性和耐水性，研究了高碱废液掺量和水灰比对其固化体力学性能的影响。结果表明：一定范围内，矿渣能有效改善AKSHC基材力学性能；矿渣掺量增加，AKSHC基材孔体积逐渐增大，孔集中分布在15～90nm的范围内；AKSHC20固化体强度随高碱废液加入量增加、水灰比减小而提高。     

碱激发赤泥-矿渣地质聚合物制备及力学性能研究

采用氢氧化钠和水玻璃复合碱激发剂对赤泥-矿渣进行活性激发制备地质聚合物,研究了矿渣的掺量、激发剂模数及固含量对赤泥-矿渣地质聚合物力学性能的影响,并对地质聚合物的产物及微观结构进行了分析。结果表明:当矿渣掺量低于50%时,随着矿渣掺量的增加地质聚合物的抗压强度逐渐增大。但当矿渣掺量过高时,地质聚合物的抗压强度反而会下降,矿渣掺量为70%的地质聚合物28d抗压强度与矿渣掺量为50%时相比下降了6.75%。赤泥-矿渣地质聚合物在水化反应过程中逐渐生成新的蜂窝状和片层状的无定形态凝胶相结构,且通过能谱分析得出该凝胶相结构为N-A-S-H凝胶和C-A-S-H凝胶组成的混合体。     

脱硫石膏-地聚合物固化软土的抗压强度

采用脱硫石膏-地聚合物作为固化剂固化软土,通过强度试验研究在不同硅铝原料配比时,碱激发剂模数、含量和脱硫石膏的掺量对固化软土抗压强度的影响,并通过扫描电镜试验和X射线衍射试验分析固化软土的微观结构变化。结果表明：脱硫石膏-地聚合物可有效提高软土的抗压强度;碱激发剂的最佳模数和含量分别为0.8和6%;脱硫石膏对地聚合物固化软土的抗压强度有促进作用,硅铝原材料中含有30%矿渣的固化软土抗压强度提升幅度大于100%粉煤灰。地聚合物固化软土生成C-(A)-S-H和N-A-S-H胶结物,加入脱硫石膏后生成了钙矾石,两者共同作用是脱硫石膏-地聚合物提高固化软土抗压强度的主要原因。该研究结果可为地聚合物应用于实际工程中软土地基处理提供参考。     

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。     

矿渣-钢渣发泡混凝土的制备及反应机理

为了实现高炉矿渣、转炉钢渣的高附加值综合利用,以水淬高炉矿渣和转炉钢渣为主要原料,加入少量的脱硫石膏、石灰和水泥熟料,通过铝粉发气制备发泡混凝土.测试了不同矿渣-钢渣掺量制备的发泡混凝土制品3、7、28 d的抗压强度和容重,并用扫描电子显微镜和X射线能谱仪分析了发泡混凝土制品养护过程中的水化产物和微观结构的变化.结果表明,钢渣掺量为30％、矿渣掺量为45％时,两者的协调性比较强,制品的抗压强度达到5.1 MPa,绝干容重为625 kg/m3;该凝胶体系中有钙矾石和C-S-H凝胶协同生成,且转炉钢渣的水硬活性明显低于水淬高炉矿渣.     

Synthesis and heavy metal immobilization behaviors of fly ash based gepolymer

Two aspects of studies were carried out: 1) synthesis of geopolymer by using fly ash and metakaolin; 2) Immobilization behaviors of fly ash based geopolymer in a presence of Pb and Cu ions. As for the synthesis of fly ash based geopolymer, 4 different fly ash content (10%, 30%, 50%, 70%) and 3 types of curing regimes (standard curing, steam curing and autoclave curing) were investigated to obtain the optimum synthesis condition based on the compressive and flexural strength. The experimental results show that geopolymer, containing 30% fly ash and synthesized at steam curing (80° for 8 h), exhibits higher mechanical strengths. The compressive and flexural strengths of fly ash based geopolymer reach 32.2 MPa and 7.15 MPa, respectively. Additionally, Infrared (IR) and X-ray diffraction (XRD) techniques were used to characterize the microstructure of the fly ash geopolymer. IR spectra shows that the absorptive band at 1086 cm⁻¹ shifts to lower wave number around 1033 cm⁻¹, and the 6-coordinated Al transforms into 4-coordination during the synthesis of fly ash based geopolymer. The resulting geopolymeric products were X-ray amorphous materials. As for immobilization of heavy metals, the leaching tests were employed to investigate the immobilization behaviors of the fly ash based geopolymer synthesized under the above optimum condition. The leaching tests showed that fly ash based geopolymer can effectively immobilize Cu and Pb heavy metal ions, and the immobilization efficiency reached 90% greater when heavy metals were incorporated in the fly ash geopolymer in the range of 0.1% to 0.3%. The Pb exhibits better immobilization efficiency than the Cu, especially in the case of large dosages of heavy metals.     

高钙粉煤灰地聚合物固化/稳定重金属的试验研究

利用高钙粉煤灰研制地聚合物来固化/稳定重金属,采用静态和动态浸出试验研究了高钙粉煤灰地聚合物对重金属的固化/稳定效果,并进一步探索了重金属的迁移机制和长期安全性.研究表明:高钙粉煤灰地聚合物分别固化/稳定0.025％的铅,0.025％的铬和0.01％的汞后,经静态浸出试验,重金属浸出浓度远低于规定的上限值,且固化率均在98％以上.经动态浸出试验,重金属的实时浸出浓度低于规定的上限值,累积浸出浓度在72 h后趋于稳定;固化体中重金属的径向分布相似;重金属的有效扩散系数和浸出率非常低,长期安全性优良.     

粉煤灰地聚合物材料及性能研究

采用正交试验研究矿渣掺量、生石灰掺量和NaOH溶液浓度三个因素对以矿渣为矿物掺合料的粉煤灰地聚合物材料强度的影响.试验结果表明,生石灰掺量和NaOH溶液浓度对该材料强度起主要作用,而矿渣可以提高该材料的早期强度.此外,对比研究掺不同矿物掺合料的粉煤灰地聚合物材料以及普通硅酸盐水泥的碱集料反应性能,结果表明,粉煤灰地聚合物材料的抗碱集料反应性能均优于普通硅酸盐水泥,而掺矿渣的粉煤灰地聚合物材料的抗碱集料反应性能是粉煤灰地聚合物材料中最好的.     

不锈钢冶炼电炉渣结构性质及浸出行为研究

研究电弧炉（EAF）渣的结构性质及渣中重金属离子的浸出行为。结果表明,EAF渣呈碱性,渣中Fe、Cr和Ni等金属元素主要以金属颗粒、（Cr,Al）2O3和（Fe,Mn,Mg）（Cr,Al）2O4晶体形式存在,具有较高的回收价值;电炉渣中可浸出重金属离子含量未超出国家标准,但存在Cr（III）再氧化为Cr（VI）的可能;Cr（VI）浸出量随浸出时间延长而增加,且Cr（VI）在蒸馏水中的浸出能力较冰醋酸中强。因此,EAF渣应尽量避免堆放或填埋在低pH场所,以防止其中重金属离子浸出。     

Static and dynamic leaching experiments of heavy metals from fly ash-based geopolymers

The feasibility of high calcium fly ash (CFA)-based geopolymers to fix heavy metals were studied. The CFA-based geopolymers were prepared from CFA, flue gas desulfurization gypsum (FGDG), and water treatment residual (WTR). The static leaching showed that heavy metals concentrations from CFAbased geopolymers were lower than their maximum concentration limits according to the U.S. environmental protection law. And the encapsulated and fixed ratios of heavy metals by the CFA-based geopolymers were 96.02%–99.88%. The dynamic real-time leaching experiment showed that concentration of Pb (II) was less than 1.1 μg / L, Cr (VI) less than 3.25 mg / L, while Hg (II) less than 4.0 μg / L. Additionally, dynamic accumulated leaching concentrations were increased at the beginning of leaching process then kept stable. During the dynamic leaching process, heavy metals migrated and accumulated in an area near to the solid-solution interface. When small part of heavy metals in “the accumulated area” breached through the threshold value of physical encapsulation and chemical fixation they migrated into solution. The dynamic leaching ratios and effective diffusion coefficients of heavy metals from CFA-based geopolymer were very low and the long-term security of heavy metals in CFA-based geopolymer was safe.     

Melting reconstruction features and solidification mechanism of heavy metal-containing slag

The relationships between microstructure and melting temperature of slag containing different heavy metals(Zn, Cu, Pb and Cr) were studied. Furthermore, the corresponding solidification mechanism and rule of heavy metals were analyzed by microscopic tests during melting and reconstructing process. Based on preliminary results, three conclusions were derived. Firstly, pure slag would begin to melt when the temperature reached 1 180 ℃; however, Zn did not play any fluxing action. Secondly, upon adding Cu and Pb, the initial melting temperature of slag decreased by 5-8 ℃ and their fluxing effect was observed. Thirdly, the initial melting temperature and the reaction time for slag decreased by 22 ℃ and 6 s respectively after adding Cr; the fluxing action was significant under Cr. The results of X-ray diffraction(XRD) and Fourier transform infrared spectroscope(FTIR) analyses showed that the above heavy metals had little influence on the reconstruction of slag. Toxicity characteristic leaching procedure(TCLP) leaching tests showed a good solidification effect of the heavy metals with melting slag, fixation rate of Zn, Cu, Pb and Cr was 36.3%, 24.6%, 9.2% and 93.2%, respectively. The leaching toxicity of the heavy metals met the requirements for environmental emission after solidification treatment.     

利用热等离子体熔融垃圾焚烧飞灰

为了评价垃圾焚烧飞灰的热等离子体熔融处理效果, 研究SiO2和CaO对重金属固化效果和重金属毒性浸出特性的影响. 在飞灰中添加一定比例的SiO2和CaO, 配置成不同的配灰样品, 利用纯氩热等离子体在1 400～1 500 ℃下, 对飞灰及配灰进行熔融玻璃化的实验研究, 分别利用X射线能量色散谱仪(EDX)、场发射扫描电子显微镜(FSEM)、X射线衍射仪(XRD)和毒性浸出方法(TCLP)分析飞灰和熔渣的化学组成、微观结构、晶相组成和重金属毒性浸出特性. 结果表明, 热等离子体熔融所得熔渣为无定形的玻璃体, 重金属浸出质量浓度均远低于毒性标准. SiO2和CaO的添加都可以改善重金属固化效果, CaO比SiO2对Cu、Zn、Cd和Pb挥发的抑制效果更好. SiO2的添加可以改善熔渣中重金属的浸出特性, 而CaO的作用与之相反.     

Kinetics of the leaching of TiO2 from Ti-bearing blast furnace slag

Ti-bearing blast furnace slag is a valuable secondary resource containing about 24 percent of TiO2. In this paper a process of leaching Ti-bearing blast furnace slag with sulfuric acid to recover TiO2, and the kinetics of that reaction, are described. Under laboratory conditions the rate is controlled by a chemical reaction. The leaching reaction is in accord with a shrinking un-reacted-core model. The apparent reaction order of the leaching reaction was 1.222 and the apparent activation energy was 87.01 kJ/mol. The model fits the observed data well until 90% of the TiO2 has be leached from the particles. The model disagrees with observations during later periods of the reaction because the solution becomes supersaturated with Ti ions, which precipitate as H2TiO4. The assumptions of constant reactant concentration and that there is no effect from the product layer on diffusion, also cause the model to deviate from the actual values.     

粉煤灰基地聚合物修补材料的组成设计与性能

以粉煤灰、矿粉两种工业废料为主要原材料,模数为1.2~1.8的水玻璃作为激发剂制备地聚合物。采用五因素四水平的正交试验组成设计方案,测试了水胶比(W)、碱激发剂掺量(S)、矿粉取代率(B)和水玻璃模数(M)在不同水平下试样的流动度、凝结时间、抗压强度和拉伸粘结强度。通过对结果进行极差分析和因素指标分析,得出这种绿色环保型修补材料的组成设计与性能指标之间的关联。综合分析得出,当水胶比为0.28,碱激发剂掺量为0.14,矿粉取代率为0.4,水玻璃模数为1.2时,制备出的地聚合物性能良好,达到绿色环保型建筑修补材料的要求。     

粉煤灰-矿渣基地聚物混凝土力学性能与微观结构

为考察不同配合比对地聚物混凝土性能的影响,开展了粉煤灰与矿渣比例、水玻璃模数以及水玻璃掺量(质量分数)对其宏观力学性能影响的实验研究,并从微观层次扫描电子显微镜(SEM)、能量弥散X射线分析(EDS)、X射线衍射(XRD)、傅里叶红外光谱(FT-IR)以及压汞实验(MIP)对微观结构进行研究.结果表明:养护龄期的增加,...