电站锅炉中粉煤灰与SiC耐火材料结渣性研究

本文主要研究含Cr2O3的硅酸锆结合SiC耐火材料的抗粉煤灰侵蚀规律,将两种不同的粉煤灰平铺在SiC耐火材料上,作用温度为1250～1450 ℃,保温时间为40小时,然后用视频光学显微镜和XRD衍射图谱来确定其显微结构和物相组成,初步实验结果表明SiC质耐火材料具有较好的抗煤灰侵蚀性能.     

Application of thermal analysis to study smelting reduction kinetics

A thermal analysis study on the reduction of iron oxide rich slags under different conditions is presented in this paper. The effects of important process variables such as time, temperature, lime-silica ratio, FeO level in slag etc. are discussed. It is shown that the mechanism of reduction by externally added graphite is different from that by a carbon saturated bath although the activation energy values are similar.     

水淬渣-累托石颗粒吸附材料的制备及应用

研究了水淬渣-累托石颗粒吸附材料制备工艺条件、再生方法及其去除铜冶炼工业废水中重金属的条件.试验结果表明,累托石与水淬渣的比例为1∶1,另加入10%的添加剂(IS)和50%的水,焙烧温度为400℃时,制成的颗粒吸附材料体积密度为1.06kg/m3,显气孔率为62.29%,吸水率为58.82%,抗压强度为2.22Mpa,吸附效果好,散失率较低.在未调节铜冶炼工业废水pH值的条件下,颗粒吸附材料用量为0.05g/cm3,反应时间为40min,吸附温度为25℃(常温)时,Cu2 、Pb2 、Zn2 、Cd2 、Ni2 的去除率分别为98.2%、96.3%、78.6%、86.2%、64.2%,处理后的水符合国家污水综合排放标准(GB8978-1996)一级标准.颗粒吸附材料对Zn2 、Cu2 有很好的选择性.吸附饱和的颗粒吸附材料用1mol/L氯化钠溶液再生效果好.该颗粒吸附材料具有分离容易、可重复使用、处理效果好、应用前景广阔的优点.     

Design and Application of a Set of Vitreous Standards for EDS-SEM Microanalysis of Melting Shop Slags

Non-metallic inclusions in steel are formed due to interactions between liquid steel and its environment in the melting shop (refractories and slags). Particles not trapped in the slag remain in the cast steel, impairing steel properties in service. Inclusion composition varies and certified standards covering the whole compositional range are unavailable.The present study describes the preparation of a set of homogeneous, glassy and crystalline standards with a wide compositional range for use in analysing non-metallic steel inclusions. For this, materials were designed based on knowledge of the compositional range of interest in the Al₂O₃–SiO₂–CaO–MgO–CaF₂ system, which is the matrix of the most frequent steel inclusions. The composition and microstructural homogeneity of the reference materials was verified.     

微波加热制备含稀土(La2O3)矿渣微晶玻璃研究

利用矿渣制备微晶玻璃是提高矿产资源利用率的主要形式之一。本文以白云鄂博尾矿为原料,采用微波一步法制备了CaO-MgO-Al₂O₃-SiO₂(CMAS)系辉石相矿渣微晶玻璃。选择835 ℃作为晶化温度,研究了微波加热对微晶玻璃析晶行为和微观组织的影响。以La₂O₃作为研究变量探讨了La₂O₃添加对矿渣微晶玻璃析晶行为的作用。与传统的热处理制度相比,微波加热可以在较短的时间内达到较高的析晶效果。同时La₂O₃的添加促进了晶粒细化。由拉曼光谱分析,La离子添加会导致玻璃网络中桥氧的增多,促进了辉石相析晶。在La的添加量为4%(质量分数)时硬度最高,达到了829.22 MPa。     

以Fe2P2O7为前驱体制备LiFePO4及其电化学性能

以磷铁废渣（Fe_1.5P）和温室效应气体CO₂为原料,以磷酸为补充磷源合成磷酸铁锂（LiFePO₄）的前驱体Fe₂P₂O₇,并研究了其合成过程对LiFePO₄正极材料储能性能的影响。采用SEM观察了LiFePO₄的表面形貌,采用XRD分析了LiFePO₄和Fe₂P₂O₇的晶体结构。进一步对该方法进行优化,发现Fe_1.5P与磷酸混合物（n_Fe1.5P：n_H3PO4=1：1）在800℃热处理6 h合成的Fe₂P₂O₇对应的LiFePO₄/C电化学性能最好,在0.1C,0.2C,0.5C和1C倍率下的容量分别可达130,126,117和108 mAh·g^-1。该方法具有成本低廉,减少碳排放和环境友好等特点,为LiFePO₄正极材料的生产提出了一种新的工艺。     

Ash and Slag Waste as a Secondary Raw Material

In the process of industrial corporation activities a lot of waste, which pollutes the atmosphere, is generated, for example ash and slag. In Tomsk region, by estimates, ash stores occupy about 600 hectares, which contain about 25 million tons by weight. In Russian thermal power-stations ash disposal areas there are about 1.3 billion tons of ash, and only 10% of it is used. That is why this problem is topical enough. In this paper the scheme of producing ash ceramic bricks and complex ash and slag waste processing is shown. Besides, profitability of the project is presented.     

Fire retarded polyurethane foam composites based on steel slag/ammonium polyphosphate system: A novel strategy for utilization of metallurgical solid waste

A series of FR-RPUF composites were prepared by a one-step water foaming process with ammonium polyphosphate (APP) and steel slag (SS) as flame retardants. Thermogravimetric analysis (TG), limiting oxygen index (LOI), UL-94 vertical combustion test, microscale combustion calorimetry (MCC), TG-Fourier transform infrared spectrometry (TG-FTIR), scanning electron microscopy (SEM), Raman spectra and FTIR were used to investigate the thermal stability, flame retardancy, combustion performance, gas phase products, and char residue morphology of FR-RPUF composites. TG test results showed that the initial decomposition temperature (T_-5wt%) and char residue rate at 700°C of RPUF/APP/SS composites were significantly enhanced by the addition of APP and SS, and the thermal stability of the composites was improved. Flame retardant test results confirmed the significantly increased LOI values of RPUF/APP/SS composites with V-0 rating. TG-FTIR also confirmed the obviously decreased release of toxic gases and flammable gases in the combustion of RPUF/APP/SS composites. SEM and Raman spectra of char residues for the composites suggested that APP/SS system improved the compactness and graphitization degree of char layer for RPUF/APP/SS composite. The above researches provide a new strategy for the utilization of SS in fire safety engineering.     

Ultrasound irradiation as an effective tool in synthesis of the slag-based catalysts for carboxymethylation

Waste minimization strategy was applied in the current work for synthesis of the catalysts from industrial solid waste, namely desulfurization slag. The starting slag material comprising CaCO₃, Ca(OH)₂, SiO₂, Al₂O₃, Fe₂O₃, and TiO₂ was processed by various treating agents systematically varying the synthesis parameters. A novel efficient technique – ultrasound irradiation, was applied as an additional synthesis step for intensification of the slag dissolution and crystallization of the new phases. Physico-chemical properties of the starting materials and synthesized catalysts were evaluated by several analytical techniques. Treatment of the industrial slag possessing initially poor crystal morphology and a low surface area (6 m²/g) resulted in formation of highly-crystalline catalysts with well-developed structural properties. Surface area was increased up to 49 m²/g. High basicity of the neat slag as well as materials synthesized on its basis makes possible application of these materials in the reactions requiring basic active sites. Catalytic performance of the synthesized catalysts was elucidated in the synthesis of carbonate esters by carboxymethylation of cinnamyl alcohol with dimethyl carbonate carried out at 150 °C in a batch mode. Ultrasonication of the slag had a positive effect on the catalytic activity. Synthesized catalysts while exhibiting similar selectivity to the desired product (ca. 84%), demonstrated a trend of activity increase for materials prepared using ultrasonication pretreatment. The choice of the treating agent also played an important role in the catalytic performance. The highest selectivity to the desired cinnamyl methyl carbonate (88%) together with the highest activity (TOF₃₅ = 3.89*10⁻⁷ (mol/g*s)) was achieved over the material synthesized using 0.6 M NaOH solution as the treating agent with the ultrasound pre-treatment at 80 W for 4 h.     

利用铝废渣制备片状堇青石的影响因素研究

以铝厂废渣、高岭土、滑石为主要原料,采用固相法合成片状堇青石。分析了原料种类、原料配方、烧结温度、保温时间和晶核剂对合成堇青石的影响,并通过XRD、SEM进行表征。结果表明,原料的纯度越高合成的堇青石纯度越高;富含镁的配方能完全形成堇青石相;最佳烧成温度为1 380℃,保温时间为4 h,此时得到的堇青石纯度最高,且呈现片状结构,颗粒大小均匀;堇青石熟料可以起到晶核剂的作用,促进堇青石的生成。