热压含碳球团高温冶金性能的实验研究

热压含碳球团是一种利用煤热塑性提高强度的新型炼铁原料。在实验室条件下，对碱度1．2和FC／O比1．0的未热处理和热处理热压含碳球团，分别检验其低温还原粉化、还原膨胀、还原冷却后强度等高温特性，并与其他炼铁原料进行合理对比。实验结果表明，热压含碳球团的高温冶金性能优于普通球团矿或烧结矿，适用于炼铁生产。     

转底炉工艺处理印度铁矿石应用研究

以印度铁矿石和煤粉为主要原料,研究转底炉金属化球团工艺处理印度铁矿石的可行性,对含碳球团进行焙烧,考察配碳比、焙烧时间、焙烧温度对球团金属化率的影响,确定了最佳工艺参数,即C/O原子比为1.2、焙烧时间21rmin、焙烧温度为1 225℃时,球团铁含量、金属化率分别达到85.1％、96.2％,此工艺参数满足转底炉高效还原的特点,适用于转底炉工艺,产品可直接用于电炉炼钢.     

硫酸渣煤基直接还原应用基础研究

以硫酸渣和煤粉为主要原料,对硫酸渣含碳球团进行焙烧,考察焙烧时间、焙烧温度、配碳量对球团金属化率的影响,确定了最佳工艺参数,即焙烧温度为1 225℃、焙烧时间15 min、(C)/(O)为1.2时,球团金属化率可达92.5%,此工艺参数满足转底炉高效还原的特点,适用于转底炉工艺。     

顺流加热含碳球团直接还原的实验研究

提出了一种顺流加热含碳球团直接还原的新方法。就对含碳球团金属化率影响最大的3个因素：还原时间、空气预热温度和料层厚度,分别按两因素三水平做了正交实验,并对实验结果进行了正交回归分析,找到了在本实验条件下含碳球团直接还原的最佳参数。这对今后在这方面的研究有一定的借鉴性。     

某燃煤电厂600MW机组燃用新煤种的适应性研究

肖家洼矿煤为华电某电厂的新进煤种,为了研究此煤种是否适应于该电厂的600 MW锅炉燃烧,对此煤种及当前电厂使用的主力煤种进行了常规参数和非常规参数分析。通过煤质对制粉系统、锅炉结焦、燃烧稳定性及环境的影响,分析了煤种可否直接用于锅炉燃烧。     

含碳球团厚料层穿流干燥的实验研究

以正交原理为基础,进行了含碳球团厚料层穿流干燥研究,研究了不同热风温度、热风流速、球团初始湿含量、生球尺寸以及料层厚度对球团干燥过程的影响。由实验数据回归得到了反映以上各因素对平均干燥速率、瞬时干燥速率、干燥时间、干燥过程温度影响程度的多元指数方程,且误差在允许范围内。方程很好地反映了各个因素对球团干燥过程的影响,对含碳球团干燥有一定的指导意义。     

混煤燃烧氮析出效应的研究进展

为研究煤燃烧的氮排放状况及相应煤中含氮量、燃烧温度与其它参数的影响,对国内外相关文献进行了归纳整理分析。针对煤热解、燃烧以及混煤时的氮析出研究现状,分析了研究中存在的问题。在全面研究国内各种煤中氮的相关成分及相互影响基础上,提出形成不同煤种氮析出的统一化评判标准,开发形成基于关键参数调整优化的精准控制燃烧技术,实现在配煤掺烧的经济条件下最小化NO_x析出的技术路线体系。     

Influence of Coal Quality and Blending on the Slurriability

针对煤种理化特性参数对煤成浆性的影响,对多种具有代表性的煤进行了制浆研究,并分析了煤种的内水含量、灰分、氧含量和可磨性系数等因素与煤种成浆性间的关系.结果表明：煤种的成浆性是由多种因素决定的,煤种的成浆浓度随着内水含量的升高而降低;随着灰分的增加,煤种的成浆浓度总体呈现上升的趋势;随着氧含量的增加,煤种的成浆浓度降低;随着可磨系数的增加,煤种的成浆浓度呈上升趋势.上述几种因素之间的关系比较复杂,不能简单地用一种影响因素分析某个煤种的成浆性;由于各种单煤的性质均不相同,混合后的不同煤种在成浆过程中相互影响,因此配煤成浆性呈现出非常复杂的非线性特征.     

含水率对煤粉流动特性的影响

运用了JENIKE剪切测试方法测定了3种不同煤种煤粉的剪切强度，得出煤粉的流动函数及其它流动特性参数，研究煤粉的含水率对煤粉流动性的影响。研究结果表明：相同的煤种、相似粒径分布的煤粉随着含水率的增加，其流动函数值不断减小，流动能力变差。     

煤焦特性及其N_2O生成影响因素的实验研究

在流化床上进行了两种煤的热解及焦炭的燃烧实验,研究了煤种、粒径、热解条件对煤焦性质及Ｎ２Ｏ转化率的影响。研究结果表明：除粒径外,煤种和热解条件都对煤焦中Ｎ的Ｎ２Ｏ转化率有明显影响。     

Pressurized chemical-looping combustion of coal with an iron ore-based oxygen carrier

Chemical-looping combustion (CLC) is a new combustion technology with inherent separation of CO₂. Most of the previous investigations on CLC of solid fuels were conducted under atmospheric pressure. A pressurized CLC combined cycle (PCLC-CC) system is proposed as a promising coal combustion technology with potential higher system efficiency, higher fuel conversion, and lower cost for CO₂ sequestration. In this study pressurized CLC of coal with Companhia Valedo Rio Doce (CVRD) iron ore was investigated in a laboratory fixed bed reactor. CVRD iron ore particles were exposed alternately to reduction by 0.4 g of Chinese Xuzhou bituminous coal gasified with 87.2% steam/N₂ mixture and oxidation with 5% O₂ in N₂ at 970 °C. The operating pressure was varied between 0.1 MPa and 0.6 MPa. First, control experiments of steam coal gasification over quartz sand were performed. H₂ and CO₂ are the major components of the gasification products, and the operating pressure influences the gas composition. Higher concentrations of CO₂ and lower fractions of CO, CH₄, and H₂ during the reduction process with CVRD iron ore was achieved under higher pressures. The effects of pressure on the coal gasification rate in the presence of the oxygen carrier were different for pyrolysis and char gasification. The pressurized condition suppresses the initial coal pyrolysis process while it also enhances coal char gasification and reduction with iron ore in steam, and thus improves the overall reaction rate of CLC. The oxidation rates and variation of oxygen carrier conversion are higher at elevated pressures reflecting higher reduction level in the previous reduction period. Scanning electron microscope and energy-dispersive X-ray spectroscopy (SEM-EDX) analyses show that particles become porous after experiments but maintain structure and size after several cycles. Agglomeration was not observed in this study. An EDX analysis demonstrates that there is very little coal ash deposited on the oxygen carrier particles but no appreciable crystalline phases change as verified by X-ray diffraction (XRD) analysis. Overall, the limited pressurized CLC experiments carried out in the present work suggest that PCLC of coal is promising and further investigations are necessary.     

Catalytic steam gasification of Mengdong coal in the presence of iron ore for hydrogen-rich gas production

Hydrogen-rich gas production from catalytic steam gasification of coal was investigated in the presence of iron ore in a vertical fixed bed reactor. The addition of iron ore significantly promoted the H₂ yields. The effects of operation parameters (upper zone temperature, lower zone temperature, steam concentration, and iron to coal ratio) on the yield of selected gaseous products (H₂ and CO) during catalytic steam gasification, were studied using Taguchi method. The results of signal-to-noise ratio indicated that steam concentration and iron to coal ratio were the most important parameters in determining the yield of H₂ and CO, respectively. Semi-quantification X-ray diffraction analysis of iron ores indicated that increase in steam concentration intensified the oxidization of low valence iron compounds to Fe₃O₄. In addition, formation of Fe₃O₄ was also favored with increasing reaction temperatures (600 °C–900 °C). However, the formation of Fe₃O₄ was inhibited at higher reaction temperature (1000 °C) due to the destruction of porous structures of the iron ore.     

研磨体级配对矿物掺合料性能的影响

本文通过矿粉、粉煤灰在不同研磨体级配情况下研磨产品的比重、比表面积、标准稠度需水量、水泥胶砂强度等性能参数的测定,得出了它们的变化规律,继而分析和探讨了不同研磨体级配对磨细矿渣和粉煤灰掺合料性能的影响.     

Production-history projections of fuels and some crucial metals in the United States

The production-history projection method of the authors is refined to determine the earliest date at which reasonably well determined depletion parameters can be ascertained. The method is applied to the United States production data for silver, crude oil, natural gas, coal, iron ore and uranium ore.     

运行参数对锅炉煤粉着火燃烧和飞灰含碳量影响的数值研究

为了达到锅炉的优化运行以保证煤粉气流及时着火和充分燃尽，采用IPSA两相流动模型和煤粉燃烧综合模型，在不同的一次风率和煤粉细度的工况下，对1台350MW锅炉煤粉燃烧过程进行了数值模拟，得出了炉内燃烧器区域以及出口处烟气温度场和燃烧产物的组分浓度分布。分析了一次风率和煤粉细度对煤粉着火燃烧和飞灰含碳量的影响规律，并确定了优化的运行参数。结果表明：一次风率对煤粉气流的着火影响较大，而对出口处烟气温度、氧量以及飞灰含碳量影响较小。煤粉细度对煤粉气流的着火、燃烧以及燃尽均有较大影响。图8表2参9     

Kinetic characterization of flash reduction process of hematite ore fines under hydrogen atmosphere

In order to attain comprehensive utilization of hematite ore fines and reduce carbon dioxide emission, the flash reduction of hematite ore fines under hydrogen atmosphere is studied. The changes of phase composition at 1450 K–1800 K are investigated. A mathematical model is developed to accurately evaluate the reduction kinetic parameters of hematite ore fines based on experiment. The complex flash reduction is accurately described by considering the multiple reaction mechanisms, including hematite thermal decomposition, gas-solid reduction and gas-liquid reduction. The activation energies of the gas-solid reduction and gas-liquid reduction at high temperature are obtained as 223 kJ mol⁻¹ and 180 kJ mol⁻¹, respectively. The developed kinetic model can well describe and predict the flash reduction process of hematite ore fines. The effects of particle size and temperature on the flash reduction process, and the contributions of the thermal decomposition, gas-solid reduction and gas-liquid reduction to the overall reaction process are clarified.     

Behavior of Fe and P during reduction magnetic roasting-separation of phosphorus-rich oolitic hematite

Fe–P separation and the behaviors of Fe and P in separation process of high-phosphorus oolitic hematite ore from western Hubei province in China were studied. Various parameters, including reducing temperature and time, dosage of the pulverized coal, grinding fineness of magnetic separation feed, magnetic field intensity and grinding fineness of flotation feed were investigated. Experimental results show that the iron concentrate with total iron grade of 61.78% and phosphorus content of 0.23% was obtained from an oolitic hematite ore containing 47.71% iron and 0.874% phosphorus by magnetization roasting-magnetic separation-reverse flotation separation process under the proper conditions. In the magnetization roasting process, the Fe and P grade was rising by 1.30% and 11.49%, respectively; the forms of Fe and P are oolite hematite (magnetite) and collophanite which mainly distributed inside oolite structure and a small portion being distributed in other shapes. In the magnetic separation process, the Fe is from 48.33% to 58.52%, and P grade was slipped to 0.70% from 0.97%, however, the forms of Fe and P have no change compared with the roasted ore. In the reverse flotation separation process, Fe is from 58.52% to 61.78%, phosphorus is from 0.70% to 0.23%, the flotation concentrate mainly contained fine iron mineral and phosphorus is finely disseminated inside the iron mineral.