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1.
污泥及其与煤混合物的热解特性和灰熔融特性   总被引:1,自引:0,他引:1  
采用热重分析法对造纸污泥、市政污泥及其与煤的混合物的热解特性进行了系统研究.揭示了污泥、煤及其两者混合物热解特性的异同,研究了升温速率、掺混比等因素对混合试样热解特性的影响,提出了挥发分综合释放特性指数.研究表明:造纸污泥的挥发分析出特性与烟煤相当,而市政污泥的挥发分析出特性远优于造纸污泥和烟煤;在污泥与煤混合物的热解过程中,2种组分之间的相互作用可以忽略不计.随着升温速率的增加,污泥与煤混合物的挥发分初析温度提高,挥发分最高析出速率和平均析出速率升高.但升温速率对挥发分析出总量没有明显影响.测定了煤灰和污泥灰在不同混合比例下的熔融特征温度,测试结果表明,随着污泥灰比例的增大,混合试样的灰熔点逐渐下降,但由于存在低温共熔现象,不按线性规律变化.  相似文献   

2.
采用热重分析法,对神府煤和蓝藻单独热解及共热解(蓝藻掺混比,即蓝藻与干基混合物的质量比为5%,10%,20%,40%和80%)特性进行了研究。研究表明:蓝藻挥发分析出的极值温度比煤低,而且热解速率比煤快。蓝藻组成复杂、挥发分含量高且含有的不稳定键多,所以在较低温度下就会被破坏,从而以较高的速率挥发出去。当蓝藻与神府煤共热解时,低温下蓝藻的挥发分析出后,暴露出来的灰分覆盖在煤的表面,灰分中具有催化作用的碱和碱土金属会加快煤的热解反应,使煤的挥发分提前析出。当蓝藻的掺混比为40%和80%时,协同作用较明显,热解焦的产率比理论值低。  相似文献   

3.
通过对非平衡等离子体及发生在内部过程的理论分析,讨论了煤在非平衡等离子体内热解制乙炔的机理,提出了这种复杂的多相反应不象一般的非平衡等离子体反应主要由活性粒子参与,而是通过等离子体中粒子的平动能将煤粒加热,使煤的挥发释放,挥发分进一步与等离子体中的活性粒子发生作用,最后裂解形成乙炔。活性粒子直接与煤粒作用难以发生煤的直接裂解。  相似文献   

4.
利用滑移电弧放电能在同一放电周期中提供平衡和非平衡等离子体条件,给出相对高能电子和提高选择性化学转化的激发性电子、原子和分子,并提供较高的功率的特点,在非平衡滑移电弧放电反应器中进行了甲烷转化制乙炔的实验研究.实验在不同反应能量密度和外加磁场强度条件下进行,对实验结果进行分析后认为天然气中甲烷的转化率、产物中乙炔的收率和选择性以及生产乙炔的能耗都随能量密度的增加而增加;在增强外加磁场强度的实验条件下,可以有效地提高甲烷反应的转化率以及乙炔的选择性和收率,同时降低乙炔的生产能耗.  相似文献   

5.
用电加热金属丝网装置在氮气气氛下进行快速热解实验,考察了温度、加热速率、压力、加热时间和煤样粒度对霍林河和义马褐煤脱挥发分的影响。结果观察到,挥发分析出率(V)随着温度的增高而增加,两种煤样的极限产率均超过了工业分析挥发分产半。加热速率对最终挥发分析出率(FV)的影响不仅因煤种而异,而且与终温有关,对于霍林河煤加热速率没有影响;对于义马煤,在600℃下,加热速半亦无影响,而在800℃下,FV随加热速率的提高呈现上升趋势。煤样粒度的影响类似于加热速率。没有观察到压力对FV的明显影响。  相似文献   

6.
基于Na,K盐含量控制对新疆低变质煤热解炼制油气品质的重要作用,通过建立固定床热解实验台,考察了淖毛湖煤在还原性气氛下热解温度对碱金属的迁移转化特性的影响。研究结果表明,淖毛湖原煤中Na主要以水溶态形式存在,K主要以不溶态形式存在。随着热解温度的升高,半焦收率呈先快速降低后缓慢降低的趋势,焦油收率呈先升高后降低的趋势。当热解温度低于600℃时,随着热解温度的升高,水溶Na向不溶Na转变;但当热解温度高于600℃时,不溶Na开始向水溶Na转化。在低温条件下,煤中的不溶K大量释放,酸溶K含量呈上升趋势;当温度高于600℃时,不溶K含量的下降速率减慢,水溶K含量增加。此外,热解释放的Na,K主要存在于焦油中,气体中含量相对较少。  相似文献   

7.
煤的热解研究:II.煤化程度对氢气氛下热解的影响   总被引:2,自引:1,他引:1  
对我国18种具有代表性的不同煤化程度的煤(Φ3mm),在氢气氛、0.1MPa和900℃条件下进行了热解实验研究。考察了煤化程度对热解转化率和热解产物产率的影响;煤中挥发分与甲烷产率的关系;煤中氧含量与CO、CO2产率的关系以及煤种对热解气热值的影响,得到了描述热解气产率与煤中挥发分的关系式。  相似文献   

8.
对我国18种具有代表性的不同煤化程度的煤(Φ3mm),在氢气氛、0.1MPa和900℃条件下进行了热解实验研究。考察了煤化程度对热解转化率和热解产物产率的影响;煤中挥发分与甲烷产率的关系;煤中氧含量与CO、CO2产率的关系以及煤种对热解气热值的影响,得到了描述热解气产率与煤中挥发分的关系式。  相似文献   

9.
几种褐煤的超临界萃取研究   总被引:1,自引:0,他引:1  
用超临界萃取方法对褐煤进行萃取研究,在半连续实验装置上进行了8种中国褐 煤样萃取试验.用甲苯作溶剂非等温萃取,萃取压力为10MPa.试验结果表明,萃 取转化率和萃取物产率与煤样挥发分呈线性关系,转化率介于30%-545;萃取物 产率介于19%一32%.加入10%四氢萘于甲苯溶剂中.转化率由38%增至62%, 萃取物产率由20%增至40%,对过程进行了动力学处理,动力学参数与煤的H/C 原子比有线性关系。  相似文献   

10.
为了获得高含水率褐煤在移动床内不经预处理直接热解的可行性及其热解行为,建立管式炉移动床褐煤直接热解实验装置;考察含水率、热解温度和粒径等参数对褐煤热解损失质量、产物产率以及产气特性的影响。研究结果表明:褐煤在热解过程中蒸发出的原位水蒸气参与半焦的气化以及挥发分的重整反应;随着含水率的增加,褐煤的原位水蒸气气化反应加强,碳转化率逐渐提高,H_2产率由277.13 m L/g增大至527.77 m L/g;提高热解温度使气体产率逐渐增大,液体和固体产率逐渐降低,碳转化率由38.19%增大至52.74%;增大粒径使煤中水分和挥发分在颗粒内部的停留时间延长,在一定程度上强化半焦的气化反应以及挥发分的重整反应;此外,增大粒径使挥发分在褐煤颗粒孔隙中的传质阻力增大,二次反应加强,褐煤直接热解的最佳粒径为1.6~3.2 mm。  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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