煤加压催化气化研制城市煤气——Ⅰ.大同煤和煤焦的催化气化特性

为了达到在单段反应器内用大同煤制造城市煤气的可能性,利用这种煤及其煤焦在压力0.1—4.0 MPa和反应温度700—900℃下通过Na_2CO_3作催化剂进行了蒸汽催化气化研究。实验结果表明,在850℃和1.1—2.1 MPa条件下,不计CO_2的产品气热值为16288—17163 kJ/NM~3(低热值为14672—15856kJ/NM~3)由于我国现行的城市煤气热值标准为14651kJ/NM~3(或3500kJ/NM~3),所以利用Na_2CO_3作为大同煤气化的催化剂是可取的。     

流化床气化温度对生物质燃气热值的影响研究

在流化床气化实验装置上对稻壳在600~700℃、700~800℃、800~900℃、900~1000℃温度范围下进行气化实验。实验结果表明:(1)气化温度为600~700℃时,炉内有残炭存在;(2)气化温度800~900℃时,燃气品质要好于700~800℃,为最佳气化温度;(3)气化温度为900~1000℃时,气化炉底部温度过高时会瞬间导致结渣现象。     

煤无焦油气化的实验研究

根据上吸式和下吸式气化炉特性,设计开发了喉口型双氧化层煤无焦油气化炉,并在煤无焦油气化炉实验装置上进行了煤无焦油的气化实验研究,考察了气化炉操作参数对主要气化指标的影响.结果表明,喉口型双氧化层气化炉内气化状态良好,出炉煤气中焦油含量大大降低,煤气热值明显提高,煤气中焦油含量最低仅为10 mg/m3,煤气热值高达6 466.9 kJ/m3,完全满足各种燃烧器和加热工艺要求,实现了煤无焦油气化;操作参数对气化指标的影响本质上是通过改变气化温度来实现的,气化温度的提高促进了焦油的裂解反应,从而提高了气化煤气中CO和H2的含量,降低了煤气中CO2和焦油的含量,使煤气热值升高.     

固定床生物质气化机组主要技术性能试验研究

采用气相色谱议等仪器,测试并检验了固定床生物质气化机组的炉膛温度分布、燃气组分、低位发热量及杂质含量等主要性能指标,同时分析了物料种类、气化强度、炉膛温度、二次风系数等因素对气化效果的影响,初步探索了生物质气化机组设计的一般规律.研究结果表明:气化强度在200kg/m3.h左右时,生物质燃气的低位发热量和杂质含量可取得最佳值;二次风系数控制在20-25%之间,炉膛内还原区温度在700℃左右,可以保证较好的燃气质量.     

温度对天然焦蒸汽气化特性的影响

在小型流化床实验装置(φ50 mm、高1.6 m)上,考察了温度对沛城煤矿天然焦蒸汽气化产气量、碳转化率、煤气热值和煤气组分的影响,并与ASPEN PLUS模拟结果进行了对比.实验结果表明:反应温度是影响气化反应的主要因素,温度升高,煤气组分中H2和CO2含量下降,CO含量增加;当气化反应温度从850 ℃提高到1 000 ℃,碳转化率从10.25%提高到47.76%,产气量增加了4.3倍;H2和CO2的含量由63.0%和25.0%减少到59.8%和20.2%,CO含量由9.6%增加到18.5%;煤气热值从8.87 MJ/m3增加到了9.33 MJ/m3.应用ASPEN PLUS软件模拟天然焦-蒸汽气化反应过程,同时考虑碳转化率,其模拟结果与实验数据接近,误差在可接受范围内,因此ASPEN PLUS模拟对系统设计与优化具有参考意义.     

生物质微米燃料空气气化实验研究

研究了生物质微米燃料(BMF)在旋风气化炉中的空气气化特性.在没有外热源的工况下,整个气化过程所需的热能由部分微米燃料的不完全燃烧供应.研究空气当量比(ER)、微米燃料粒径对气化特性的影响.当ER=0.32时,H2的含量和气化效率最高,分别为6.32％和38.22％;当ER=0.28时,可燃气的含量最大,达到27.1％.随着BMF粒径减小,气化室温度、可燃气含量、H2的含量、碳转化率、气化效率和燃气热值都显著提高,分别可达953℃、29.7％、8.26％、60.07％、40.56％和4246kJ/m3.     

带有热管热回收装置的燃气热水器系统性能实验研究

设计了一种加装于常规燃气热水器尾部烟道的冷凝式热管换热器,通过实验测试分析了热负荷和进水流量对该换热器蒸发段显热、潜热回收量以及燃气热水器热效率的影响。实验结果表明,燃气热水器热负荷对热管换热器热回收量有重要影响,随着热负荷从0.51 m3/h增加至0.59 m3/h,显热和潜热的回收量分别从2 671 kJ/h增加至3 283 kJ/h、735 kJ/h增加至1 126 kJ/h,燃气热水器的平均热效率能够达到94%,按燃气低位热值计算,最高热效率可达到101%。     

高热值生物质燃气气化炉的数值模拟

研究了以干木质颗粒作为燃料,以空气—水蒸气作为气化剂的户用高热值燃气生物质气化炉,利用Fluent14.0模拟了水蒸气入口距离气化炉内炉栅位置高度h、空气入口流量V0与水蒸气入口流量Vs这三个参数对CO、H2和CH4的体积浓度和燃气热值影响,并采用实验验证数值模拟的结果.研究的结果表明:若水蒸气入口位置高度h=195 mm,水蒸气入口流量Vs=1.41 m3/h时,空气入口流量V0=0.86 m3/h,生物质燃气燃烧热值最大为Q=9.95 MJ/m3,相比单一空气气化剂作用下提高了98.21%.     

城市生活垃圾原料性质对干馏及气化过程的影响

将城市生活垃圾样品经预处理后置于φ40×750不锈钢间歇式固定床气化炉内进行气化反应,考察不同原料组分对垃圾干馏与气化过程的影响。认为城市生活垃圾的有机物部分作为制气原料,气化活性较高(1000℃时CO_2转化率达92％)。气化强度大,燃气组分与煤制气组分基本接近。试验结果得干馏阶段燃气热值一般在9.62～10.04 MJ/m~3(2300～4000 Kcal/m~3),气化阶段燃气热值在3.35～4.18 MJ/m~3(800～1000 kcal/m~3),垃圾有机物中灰分、固定碳和挥发分对干馏和气化过程均有影响。考察干馏和气化的综合效果,当反应温度为900℃,混合气为气化剂时,燃气热值可达4.60～5.65 MJ/m~3(1100～1350 kcal/m~3),但气体产率不大于1.5 m~3/kg。     

城市固体垃圾热解设备与特性研究

针对无筛分城市垃圾热解的实用技术进行了研究,开发出内热源和外热源联合使用的垃圾热解设备.同时对设备的温度变化、垃圾热解特性、产气规律以及影响热解气热值的主要因素等进行了详细的分析.结果表明:实用热解设备的产气率高,理想热解温度在700℃以下.垃圾热解气中H2的体积分数达15.2%,C2H4,C2H6,C3H6和CH4的体积分数总和是10%,热解气的平均热值为7546.4 kJ/m3.设备运行稳定且温度特性满足设计要求.     

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

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