炼焦配煤中添加铁矿石对焦炭性能的影响

通过在炼焦配煤中添加不同配比的加拿大精矿粉、澳大利亚FMG粉和鄂西高磷铁矿粉炼制铁焦,并对其显微强度、相对密度、气孔率、冷强度、反应性、反应后强度和气化反应开始温度进行分析,探讨配煤中添加铁矿石对焦炭性能的影响。结果表明,在配合煤中添加质量分数为15%的加拿大精矿粉所制得的铁焦在反应性高的情况下,具有合适的反应后强度;金属铁对焦炭气化反应具有正催化作用。     

焦炭初始反应温度影响因素分析

通过配煤炼焦实验,研究入炉煤的性质、炼焦工艺和添加剂对焦炭初始反应温度的影响。结果表明,不管是单种煤还是配合煤,焦炭初始反应温度均随入炉煤煤化度的提高而上升;随着焖炉时间的延长,焦炭初始反应温度显著升高;随着入炉煤细度的增加,焦炭初始反应温度有所升高,而入炉煤的堆积密度对焦炭初始反应温度基本没有影响;具有催化作用的添加剂能显著降低焦炭的初始反应温度,而添加铁矿粉对焦炭初始反应温度的影响较消石灰的影响更为明显。     

基于模型的铁焦强度预测及其控制途径分析

为了预测、改善和控制铁焦的强度,通过6个配煤方案、72组炼焦试验,系统地研究了铁矿粉配比w、入炉煤堆积密度d、入炉煤挥发分质量分数w(Vdaf)和粘结指数G对铁焦强度的影响。在此基础上,以上述4个因素为参数建立了铁焦强度的预测模型。该模型揭示了各因素对铁焦强度的影响规律和各因素的适宜值,预测精度较高;根据预测模型分析了控制铁焦强度的途径。     

铁焦工业生产前几个主要问题的初步研究

在五种变质程度不同的煤（Г,ГЖ　ПЖ,КЖ,Ｋ） 中,加入不同数量的磁铁矿贫选粉进 行小焦炉炼焦试验。试验表明：开始加入贫选粉时,铁焦的抗碎强度增高,然后下降;铁焦 的磨损性则随贫选粉加入量的增多而增大。在我们的试验中,最高强度的的贫选粉加入量 为１５—２５％。然后用单种煤和配煤加入贫选粉进行了铁箱炼焦试验。小焦炉和铁箱炼焦试验 都表明：峰一煤最适合于炼制铁焦,双鸭煤可作为炼制铁焦的配料中的主要组成。此外,也 研究了一些与炼制铁焦有失的主要问题：如结焦时间,偏析作用,堆积比重的变化等。在这 些研究的基础上提出了铁焦大炉试验的配煤方案。     

工艺参数对热压铁焦抗压强度的影响

热压铁焦是一种新型含碳复合炉料,高炉使用铁焦有助于降低热空区温度、减少CO_2排放.研究了工艺参数对热压铁焦抗压强度的影响,并分析其作用机理.研究结果表明,在一定范围内,铁焦抗压强度随着铁矿粉配比增加先增加后降低,在矿粉配比15%时取得较大值3 490.89 N;随着烟煤配比的增加而提高;随着热压温度的提高而提高,在热压温度350℃时取得较大值4 305.50 N;随着炭化温度的提高先降低后提高;随着炭化时间的增加先提高后降低,在炭化时间4 h时取得较大值3 518.80 N.从抗压强度角度考虑,热压铁焦合适的制备工艺参数为10%~15%铁矿粉,60%~70%烟煤,热压温度300~350℃,炭化温度1 000~1 100℃,炭化时间2~4 h.     

堆积密度对捣固炼焦焦炭性能的影响

采用5个配煤方案进行捣固炼焦试验,研究不同的堆积密度对焦炭性能的影响.结果表明,入炉煤堆积密度对焦炭的灰分和硫分基本没有影响,而对焦炭的气孔率、冷态机械强度及热性质影响显著.捣固炼焦的最佳堆积密度为0.9～1.1 t/m3.最佳堆积密度及在最佳密度下的焦炭性能还受配合煤性质的影响.     

入炉煤性质对捣固焦炭性能的影响

采用30种配煤方案,在堆积密度为1.1t/m3的条件下进行捣固炼焦试验,利用线性回归分析方法研究入炉煤性质对焦炭性能的影响。结果表明,焦炭性能指标与入炉煤性质指标之间具有良好的相关性;适当降低入炉煤的挥发分有利于提高焦炭的冷态机械强度,而增加入炉煤的黏结指数有利于提高焦炭的耐磨强度,但不利于提高焦炭的抗碎强度;适当降低入炉煤的挥发分和催化指数、提高其黏结指数有利于改善焦炭的高温反应性。     

捣固炼焦工艺分析

简要分析了可扩大炼焦用煤范围的捣固炼焦工艺。捣固炼焦工艺是通过增加入炉煤的堆比重,以改善入炉煤的结焦性能,使得在配煤炼焦中可大量增加气煤及弱粘煤等传统焦炉极少用到的煤种的配入量,从而降低配煤、吨焦成本,并能够得到令人满意的焦炭质量,同时提高企业经济效益。     

东北几种煤予热炼焦

在废气流中,进行了单种煤和配煤予热。煤予热温度采取７０,１５０,２００,２５０,四个点,煤予热后用胶质层测定仪进行了炼焦,焦饼进行了转鼓试验。煤予热后炼焦,＞２５ｍ／ｍ焦块增多,＜１０ ｍ／ｍ的粉焦减少。结焦性提高效果,因煤种而异。年青的气媒效果最好。 合适的煤予热温度在２００－２５０℃,煤干燥（予热温度７０℃）结焦性变化不大。煤予热炼焦实验表明,气煤可多配至 ５５－７０％,能解决因予热而产生的难推焦,又扩大炼焦煤源。煤干燥炼焦;不能多配入气煤。     

几种石油焦在炼焦配煤中的配伍性

研究荆门石油化工厂、岳阳长岭石油化工厂和武汉石油化工厂生产的三种石油焦的性质及其在炼焦配煤中的配伍性。试验结果表明，添加任何一种石油焦，对炼焦配煤都具有减灰增硫作用，黏结指数都呈下降趋势。但添加荆门焦时，增硫作用最小，黏结指数也仅下降1个单位；且收缩度平均值为19％，膨胀度平均值为18％，塑性温度范围平均值为100℃，显示荆门焦与炼焦配煤的配伍性最好。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

正~~