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1.
75t/h 水冷方型分离器循环流化床锅炉物料平衡热态测试   总被引:8,自引:1,他引:8  
利用自行设计的测试方法对第一台采用入口带有加速段的水冷方型分离器专利技术的75t/h循环流化床锅炉物料平衡系统进行热态测试,包括分离器的分级分离效率、烟气对固体物料的携带率、固体物料循环量等。测试结果表明:该锅炉水冷方型分离器的分级分离效率与相同当量直径的常规圆形旋风筒的分级分离效率相近,但阻力下降约一半;该炉的固体物料循环量达到设计值并有一定调节裕度,完全满足燃烧和传热的要求。测试结果为该炉型的进一步放大提供了可靠的依据。  相似文献   

2.
方形分离器入口加速段宽度   总被引:3,自引:0,他引:3  
为充分了解入口带有加速段的方形分离器的放大特性 ,如分离效率和阻力 ,在定型尺寸为 70 0 mm× 70 0 mm的冷态试验台上进行了详细的研究工作 ,还作了结构优化试验 ,确定了入口加速段宽度的最佳值。在优化结构条件下 ,分离器的切割直径为 2 8μm,临界直径为 12 5 μm,阻力因数为3.12。研究表明该分离器的性能可以满足大型循环床设计需要 ,该结果对大型循环床的设计具有重要意义  相似文献   

3.
平面流分离循环流化床锅炉改造及其运行   总被引:1,自引:0,他引:1  
出力不够是20世纪90年代初投运的第一代中国产循环流化床锅炉的主要问题。为改善75t/h平面流分离循环床锅炉的性能,在原分离器的位置空间采用入口带有加速段的方型分离器代替平面流分离器,适当调整受热面,保留现有炉型和钢构架。改造后的运行实践证明,锅炉出力可以稳定达到额定值,物料循环系统工作正常,主循环回路温度分布合理,改造是成功的。  相似文献   

4.
方型分离器进口气流速度的实验研究   总被引:2,自引:1,他引:1  
方型分离器是一种应用于循环流化床的新型气固分离装置,其性能可靠,制造成本低,结构紧凑,易于大型化.为进一步优化入口带有加速段的方型分离器操作参数,在700m m ×700m m 的冷态实验台上实验研究了进口风速对分离器性能的影响.结果表明,进口速度与d50 和d99 的关系与分离器结构有关,在比较合理的结构条件下,进口速度22.5m ·s- 1 时,d50 和d99 最低,d50 为27μm ,d99 为127μm ,流动阻力系数ξ为3.9  相似文献   

5.
循环流化床J型阀性能的冷态实验研究   总被引:1,自引:0,他引:1  
J型阀运行简单,在循环流化床锅炉得到应用.为了解J型阀的性能,在φ90mm的冷态实验台上进行了实验研究.结果表明,J型阀松动风速与物料回送截面流率呈线性关系,并具有良好的自平衡特性;阀体阻力系数在一定范围内随颗粒速度线性变化;为获得较大循环量并兼顾阻力,松动风速应在最大输送区选取。  相似文献   

6.
分离器内燃烧是循环流化床锅炉运行过程中的一种常见现象,对锅炉运行有着重大影响。文章简要分析了影响分离器内燃烧现象的一些主要因素,针对典型工况进行理论计算,并对分离器内燃烧在简单情况下的控制机理进行了分析。灰带是分离器中颗粒富集的主体,也是碳颗粒燃烧的主要地带。冷态试验结果表明,分离器内灰带圈数随入口风速增加而增加。Fluent计算结果和试验结果比较吻合。  相似文献   

7.
75t/h 水冷方型分离器循环流化床燃烧室浓度分布   总被引:6,自引:0,他引:6  
针对75t/h水冷方型分离器循环流化床锅炉,利用自行设计的测试方法进行了炉内燃烧室不同位置的局部固体悬浮浓度的测量,确定了燃烧室近壁区沿高度方向及截面方向物料浓度分布,分析了测量结果,并根据测量结果,发展了炉内局部物料浓度的计算模型。这个模型对于该炉的容量放大有指导意义。  相似文献   

8.
针对旋风分离器结构尺寸设计时缺乏数学模型指导以及锅炉实际运行时旋风分离器几何结构无法优化调整等问题,选取江苏某电厂的循环流化床锅炉旋风分离器为研究对象,采用数值模拟与试验相结合的方法对旋风分离器的性能进行研究.结果表明:当锅炉负荷降低时,圆柱体与圆锥体内切向速度与轴向速度均降低,旋风分离器内部旋转流动减弱,减小了在压降中占主要部分的内部旋转损失,总压降也随之减小;锅炉处于低负荷时,正常的入口风速会对分离效率产生较大的影响;在实际运行中,可采用增大引风机阀门开度的方法提高旋风分离器入口风速,达到提高分离效率的目的.  相似文献   

9.
循环流化床锅炉炉膛内气体浓度的分布   总被引:1,自引:0,他引:1  
循环流化床锅炉炉膛中气体组分反映了燃烧过程,影响了燃烧效率和脱硫效率.采用自行研制开发的水冷探针,对循环流化床锅炉炉膛中气体浓度分布进行了热态测试.测试结果表明,不同操作条件下沿炉膛轴向和径向气体浓度存在差异,高循环流率循环流化床锅炉存在严重的混合问题,在循环流化床锅炉燃烧室中心区存在三角形的贫氧区.二次风的穿透力直接影响到燃烧效率.增加二次风速可以使混合问题得到改善,飞灰含碳量下降.  相似文献   

10.
以山西国际能源宏光联盛一期(1x300MW)煤矸石发电工程的锅炉为例,详细介绍了循环流化床锅炉冷态通风试验的目的、内容、测点位置及数量,对试验数据进行了分析,指出了该锅炉存在的问题,提出了保障锅炉正常运行的参数。  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.
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   

18.
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   

19.
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   

20.
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   

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