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1.
稻秆热解的目的是为了脱除氧元素,增加能量密度,并将热解的固体产物作为生物质气流床气化原料,从而提高气化合成气的热值。稻秆在管式电阻炉中以5℃/min和15℃/min的升温速率进行慢速热解,热解温度为200~800℃。利用自动量热仪和元素分析仪对热解后固体产物进行热值和元素分析。结果表明:同一热解温度下,升温速率越快,半焦的热值越高;碳元素的含量随着热解温度的升高逐渐增加,而氢和氧两种元素的含量随着热解温度的升高逐渐降低。同时,推导出热值与半焦中各元素含量的关系式。  相似文献   

2.
有机垃圾在外热回转窑内热解的产物分析   总被引:6,自引:0,他引:6  
利用外热式回转窑试验台在不同热解终温下以垃圾中的典型有机物组分-废纸,PE塑料,废轮胎、木块及它们的混合物进行了一系列热解试验。考察了外热式回转窑的升温特性以及热解终温对热解气体,焦油和半焦的产率的影响。在不同的热解终温下研究了热解气体的成分、热值和能量份额的变化;研究了焦油的C/H原子比、热值和族分的变化以及半焦的热值、挥发分,固定碳,C和H元素的残余份额的变化,并对半焦的CO2反应活性进行了测  相似文献   

3.
 生物质微波热解具有反应速率快、易于控制、安全无污染等优点,但在制气方面存在产率不高、热值较低等问题,严重制约了生物质能的全面与高效利用。简述了微波热解原理,梳理了微波辅助热解技术在提升产气产率及热值、高效脱除焦油、抑制污染物生成和降低系统能耗4个方面的国内外最新研究现状,评述了当前实验用焦油模型化合物存在的局限性以及焦油在转化与脱除过程中所面临的问题,并给出了科学合理的建议。  相似文献   

4.
对东胜褐煤进行等温热解试验,分析热解温度对褐煤热解气的组成、产量和热值的影响,并利用FTIR对褐煤及其热解产物半焦的主要分子结构进行分析。结果表明,随着等温热解温度的升高,褐煤热解产物半焦中脂肪烃类结构及含氧官能团减少;热解气中CO和H2的含量逐渐增加,CO2的含量明显降低,CH4和CnHm的含量先增加后减少,热解气的产量和热值明显增加;当热解温度为700℃时可得到较高热值的热解气,此时φ(H2)高达39.5%。  相似文献   

5.
生物质的流化床热解实验研究   总被引:12,自引:2,他引:10  
用小型流化床实验台对4种农林生物质废弃物进行热解实验研究.研究发现:对所研究的生物质试样,热解温度低于500℃时,液态产物产率随着温度增加而增加.在500~600℃之间液态产物产率达到最大.当热解温度超过600℃时,液态产物产率随着温度增加而减少,气体产物产率增加,半焦产率下降.对于所研究的生物质,松木屑和甘蔗渣的半焦产率远远低于花生壳和谷壳的半焦产率.这可能是由于松木屑和甘蔗渣灰含量低于后两种生物质;另一方面也可能是由于松木屑和甘蔗渣中的无机物质(Na和K)的含量较多的缘故.  相似文献   

6.
新鲜生物质热解气化半焦特性的FTIR研究   总被引:1,自引:0,他引:1  
为了更全面地研究新鲜生物质的热解气化过程,对二种新鲜生物质不同热解气化条件下的半焦特性进行了研究。采用傅立叶变换红外光谱(FT IR)法分别考察了温度和水分对生物质热解气化半焦特性的影响。结果表明,生物质在200℃热解后各种基团量增大,此后随着热解温度的升高各基团呈逐渐减小的趋势;水分的存在有利于-OH、C=O基团脱落或转化。  相似文献   

7.
为分析石长沟油页岩和其半焦热解特性以及为半焦的有效利用提供理论基础,利用元素分析、X射线光电子能谱(X-ray photoelectron spectroscopy, XPS)分析、N2等温吸附/脱附法和扫描电镜(scanning electron microscopy, SEM)对石长沟矿区油页岩及不同热解条件下生成的半焦进行特性研究。元素分析表明,油页岩中C、H元素含量分别为11.48%、1.68%,N、S元素的含量相对较少,随热解的进行,C、H元素含量下降明显,S元素含量有所升高,N元素含量略有降低;XPS分析表明,油页岩中的氮以氧化型氮和吡咯型氮、硫以无机硫酸盐硫为主要存在形式,半焦中氮以吡咯型氮为主,有机硫化物硫随热解的进行析出;氮气等温吸附脱附实验分析表明,半焦孔隙分形维数和表面分形维数在2.5~2.8;扫描电镜结果表明,油页岩表面有机质部分多为光滑条状或块状结构,无机盐形成明显的层状结构,有机质结构热解后会形成较深圆孔隙。  相似文献   

8.
考察了煤/生物质共热解过程中煤中矿物质、煤半焦物理结构及煤中氧含量等因素对生物质碱金属在共热解过程中迁移行为的影响。结果发现:煤中矿物质和煤焦中氧含量是影响共热解过程中生物质碱金属钾再分配的主要因素;生物质碱金属钾的迁移随煤中矿物质含量(质量分数)的增加而增加,煤焦中生物质钾质量分数从17.69%增加到41.49%;迁移到共热解脱矿物质煤焦中的生物质钾与煤焦中氧的含量有关;而煤焦的物理结构对共热解过程中生物质碱金属的影响很小。  相似文献   

9.
以内蒙古锡林郭勒盟褐煤为原料,借助于煤热解制备出民用洁净低硫褐煤半焦,考察了热解温度、升温速率、恒温时间及煤粒粒径等工艺条件对所制备的褐煤半焦中总硫、有机硫及无机硫含量的影响。实验结果表明:在500~800℃热解温度范围内,褐煤半焦中总硫含量随着热解温度的增加呈现先减小后增加的趋势,热解温度为700℃时褐煤半焦中总硫质量分数达到最低值(0.98%);热解升温速率越慢,越有利于褐煤中硫的释放,升温速率为10℃/min时褐煤中硫释放程度最大(脱硫率为67%);热解恒温时间过短或过长都会影响煤中硫的脱除,最佳热解恒温时间为60 min;随着煤粒粒径的增大,热解过程中传质阻力增加,不利于煤中硫的脱除,粒径≤0.2 mm时褐煤半焦中硫含量最低。  相似文献   

10.
高硫强粘结性煤与生物质共热解脱硫脱氮的研究   总被引:1,自引:0,他引:1  
用回转炉作为高硫强粘结性煤与生物质共热解的反应器,分析了热妥过程中煤与生物质的相互作用机理,研究了热解温度、生物质汪厍量和煤粒度对无机硫脱除率、有机硫脱除率和氮脱除率的影响,结果表明,随着热解温度升高、煤化度降低、生物质添加量增大、煤粒度减小,脱硫脱氮率提高。  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
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。  相似文献   

14.
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.  相似文献   

15.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

16.
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-  相似文献   

17.
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-  相似文献   

18.
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  相似文献   

19.
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  相似文献   

20.
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  相似文献   

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