管式炉热物理量场反演

通过建立工业管式裂解炉模型,结合辐射图像处理方法,开展了管式炉炉内热物理量场反演模拟研究.针对管式炉内复杂边界条件下的辐射传递方程求解问题,在蒙特卡洛方法中加入多尺度网格及能束步进求解策略,实现了炉管、火焰和炉壁辐射的解耦计算.模拟研究结果表明,较小的测量误差条件下温度场重建误差小于4%,最大偏差小于30,K,并且能够实现对每根炉管表面温度的准确重建.该项研究将为提高管式炉安全监视和热力过程控制水平提供参考.     

油田管式加热炉炉管外壁凝水原因分析及改造

通过对油田管式加热炉燃烧和传热分析,确定了加热炉炉内凝水产生的原因并提出了具体的改造方法,对管式加热炉的设计提出了建议。     

200万千卡/时卧式圆筒管式炉

引言大庆油田会战初期到七十年代初,原油集输系统较广泛地应用方箱管式炉。到目前为止,全油田热负荷为50-200万千卡/时的管式炉473台,热负荷共计44250万千卡/时。这些加热炉热效率普遍低,根据对某站使用的200万千卡/时方箱管式炉的热效率测试,经过操作工艺条件调整,最高的热效率仅达62％,耗用了大量的能源。一九八四年初大庆石油管理局节能规划会议决定,对各采油厂的旧方箱式管式炉全部更新,需研制一种新型管式炉,热效率达80％以上。我们在1984年3月开始研制200万千     

“PERC+SE”单晶硅太阳电池氧化工艺研究

“PERC+SE”单晶硅太阳电池制备过程中,相较于传统的酸抛工艺,在碱抛光工艺之前(即氧化环节)先要制备氧化层SiO₂膜作为掩膜,以保护硅片正面。目前,行业内主要有2种制备SiO₂膜的方式,一种是采用管式扩散炉,另一种是采用链式氧化炉。从实际应用来看,相较于管式扩散炉,链式氧化炉的生产线兼容性更好,产能也更高;而从理论上来看,管式扩散炉比链式氧化炉制备的SiO₂膜更加致密,膜层对掺杂区域的保护也更好。对于这2种设备,从制备的SiO₂膜厚度,硅片氧化前、后和碱抛光后的方块电阻变化,以及制得的“PERC+选择性发射极(SE)”单晶硅太阳电池的电性能3个方面进行详细对比。结果显示：管式扩散炉与链式氧化炉制备的SiO₂膜对SE激光重掺杂区域的保护效果略有差别,但对太阳电池电性能的影响较小,可忽略。因此,结合生产线兼容性及产能情况,链式氧化炉比管式扩散炉更具有推广优势。     

太阳电池生产用管式扩散炉的数值模拟————匀流板对流场的影响

以晶硅电池生产用管式扩散炉的内部流体状况为研究对象,用计算流体力学方法对管式扩散炉进行数学建模及流体力学数值模拟计算;对扩散炉内放置与未放置匀流板的流场状况进行对比研究;分析匀流板对扩散炉内部温度场、速度场、密度梯度场的影响及成因;认为装有匀流板的扩散炉内流体的速度场可给予硅片更为充足的磷源;发现匀流板附近存在着复杂的涡流区,认为该涡流区是决定扩散炉内温度场分布均匀程度的根本原因与关键因素。     

29MW角管式热水锅炉水动力特性分析

论述了大容量热水锅炉用于集中供热的优势。对29MW角管式热水锅炉的水动力特性进行了详细分析,并提出在应用自然循环与强制循环相结合的循环方式时,既要考虑自然循环的可靠性及强制循环的安全有效性,又要避免尾部受热面的低温腐蚀。与国内其他炉型相比,29MW角管式热水锅炉具有整体优势,在我国西部大开发中该炉型将有广阔的发展前景。     

65t电弧炉石灰石炼钢工艺研究

通过管式炉实验和工业试验的方式研究电弧炉炼钢用石灰石代替部分石灰造渣工艺的可行性。管式炉实验表明石灰石的加入可以满足对终点脱磷率和碱度的要求。工业试验的试验结果表明石灰石代替部分石灰的造渣工艺在满足炼钢要求的前提下,可以使电弧炉吨钢石灰消耗降低23.3 kg,总体来说可以达到降本增效的目的。     

矿热炉水冷炉盖结构改进

现已有的矿热炉水冷炉盖结构存在不合理性,通常仅冷却炉盖骨架,没有水冷的地方很快就被烧蚀了。为了提高矿热炉炉盖的使用寿命,降低设备维修费用,对矿热炉水冷炉盖结构进行了改进,采用可拆卸管式水冷炉盖的结构形式。     

管式PECVD设备的温控系统调节对镀膜均匀性的影响分析

以管式PECVD设备的温控系统调节对镀膜均匀性的影响为研究对象,通过实验研究的方法,分别研究了温控系统调节中温区的温度设置、加热时间设置、整体温度设置,以及舟片间距设置对管式PECVD设备镀膜均匀性的影响.研究结果表明:将炉口到炉尾的温度设置为依次降低的趋势,或增加加热时间,或整体温度降低都可以缩小内、外舟片的温度差异...     

AOD炉低温段角管式余热锅炉设计及应用

新设计的用于AOD炉低温段的角管式余热锅炉,充分开发了AOD炉原废弃的低温余热资源,产生蒸汽用于生产.结合相关项目的 实际情况,为日后类似的项目提供借鉴经验,对于我国在节能增效的条件下促进AOD炉炼制不锈钢的发展具有一定的参考意义.     

Committee Report-recommended Practice on Specific Aspects of Cable Installation in Power-Generating Stations

In the late 1940's high voltage pipe-type feeders were first installed in the United States. Since that time, over 2360 circuit miles of underground high voltage pipe-type cables have been installed throughout the country. Con Edison has approximately 652 circuit miles of high pressure pipe-type cable on its system, operating at 69, 138 or 345 kV. The typical pipe-type cable system is comprised of a steel pipe, containing 3 cables, with splices located at intervals of approximately 2000 feet. The pipe is filled with dielectric fluid which is maintained at a nominal operating pressure of 200 psig. Pressurization on the feeder is maintained automatically by pumping plants. For the 345 kV system, these plants sometimes include cooling capability. As the pipe type cable system grows older, leaks of dielectric fluid develop. The major causes of leaks are corrosion, contractor damages, effects of stray currents and localized pipe wear due to vibration. Quick detection and location of dielectric fluid leaks, particularly without the need to deenergize the feeder, is of prime importance to the utility industry. Raychem Corporation has been involved with the development of sensor cables for the detection and location of fluid leaks such as water and gasoline. This technology has been enhanced to address the problem of pipe type cable dielectric fluid leaks and a new system has been developed. The new system uses a sensor cable which is buried in the trench with the pipe type cable.     

常温条件下油罐长期储存易凝高黏原油后输转作业加热方案的选择

石油储备库油罐长期储存易凝高黏原油后输转作业需要对油罐进行加热。介绍了油罐内传统管式和采用立体结构的管式全面加热技术的原理并分析了其特点。介绍了油罐内原油局部加热技术，包括油罐局部加热浮式输油装置技术、WMY快速加热器技术、电加热器技术、电磁感应加热技术、石英热管加热器技术、太阳能-电组合加热技术等。从节能降耗的角度出发，对加热方案的选择提出了建议。     

分离套管式热管蒸汽发生器在硫酸工业余热回收中的改进

在论述分离套管式热管蒸汽发生器的常规优点基础上,阐述了本设针对硫酸工业余热回收的特点而在热力方案设计及设备结构设计上做的部分改进。     

Use of Monte Carlo analysis for calculating the current rating ofcables

In this letter, the use of Monte Carlo analysis is introduced for calculating the current rating of high-pressure oil-filled (HPOF) pipe-type cable. It is shown that the current rating may differ by ±9.25% from its deterministic value if 10% variations in the random parameters of the cable system are assumed     

湿法脱硫系统吸收塔除雾器改造分析及应用

为了提高除雾效果,改善GGH堵塞情况,将原来两层平板式除雾器改造为一级管式加两级屋顶式除雾器,并详细介绍了除雾器及吸收塔的改造措施、改造工期、改造费用和改造效果,本次改造有效减少了吸收塔出口的石膏液滴含量,保证了取消旁路后脱硫系统的正常稳定运行,经济效益和社会效益显著.     

A Finite-Element Technique to Determine the Friction Factor and Heat Transfer for Laminar Flow in a Pipe with Irregular Cross Section

Abstract

A numerical analysis is developed to predict friction factors and heat transfer coefficients in a pipe with irregular cross section such as that occurring in underground, pipe-type electric cable systems. The analysis employs the finite-element method, which can be easily applied to irregular geometries and nonuniform meshes. The numerical solutions substantially agree with experimental results. The value of f Re is a function of configuration. The Nusselt number is strongly dependent on the Rayleigh number and the cable configuration, both of which affect the secondary flow.     

Research progress on hydrate plugging in multiphase mixed rich-liquid transportation pipelines

The plugging mechanism of multiphase mixed rich-liquid transportation in submarine pipeline is a prerequisite for maintaining the fluid flow in the pipeline and ensuring safe fluid flow. This paper introduced the common experimental devices used to study multiphase flow, and summarized the plugging progress and mechanism in the liquid-rich system. Besides, it divided the rich-liquid phase system into an oil-based system, a partially dispersed system, and a water-based system according to the different water cuts, and discussed the mechanism of hydrate plugging. Moreover, it summarized the mechanism and the use of anti-agglomerates in different systems. Furthermore, it proposed some suggestions for future research on hydrate plugging. First, in the oil-based system, the effect factors of hydrates are combined with the mechanical properties of hydrate deposit layer, and the hydrate plugging mechanism models at inclined and elbow pipes should be established. Second, the mechanism of oil-water emulsion breaking in partially dispersed system and the reason for the migration of the oil-water interface should be analyzed, and the property of the free water layer on the hydrate plugging process should be quantified. Third, a complete model of the effect of the synergy of liquid bridge force and van der Waals force in the water-based system on the hydrate particle coalescence frequency model is needed, and the coalescence frequency model should be summarized. Next, the dynamic analysis of a multiphase mixed rich-liquid transportation pipeline should be coupled with the process of hydrate coalescence, deposition, and blockage decomposition. Finally, the effects of anti-agglomerates on the morphological evolution of hydrate under different systems and pipeline plugging conditions in different media should be further explored.     

Energy use in Indian household sector – An actor-oriented approach

Over the years, significant changes have taken place with regard to the type as well the quantity of energy used in Indian households. Many factors have contributed in bringing these changes. These include availability of energy, security of supplies, efficiency of use, cost of device, price of energy carriers, ease of use, and external factors like technological development, introduction of subsidies, and environmental considerations. The present paper presents the pattern of energy consumption in the household sector and analyses the causalities underlying the present usage patterns. It identifies specific (groups of) actors, study their specific situations, analyse the constraints and discusses opportunities for improvement. This can be referred to “actor-oriented” analysis in which we understand how various actors of the energy system are making the system work, and what incentives and constraints each of these actors is experiencing. It analyses actor linkages and their impact on the fuel choice mechanism. The study shows that the role of actors in household fuel choice is significant and depends on the level of factors – micro, meso and macro. It is recommended that the development interventions should include actor-oriented tools in energy planning, implementation, monitoring and evaluation. The analysis is based on the data from the national sample survey (NSS), India. This approach provides a spatial viewpoint which permits a clear assessment of the energy carrier choice by the households and the influence of various actors. The scope of the paper is motivated and limited by suggesting and formulating a powerful analytical technique to analyse the problem involving the role of actors in the Indian household sector.     

生物质燃烧过程中结焦、积灰及腐蚀形成机理及其制剂开发研究进展

大力发展生活垃圾及农林废弃物等生物质直接燃烧发电和煤炭掺烧生物质燃烧发电对缓解我国能源安全问题和实现“双碳”战略目标具有重要意义。然而生活垃圾和农林废弃物中较高含量的碱/碱土金属、硫、氯和硅等元素在高温燃烧过程中会发生复杂交互反应,导致锅炉结焦、积灰和腐蚀等一系列问题,严重影响锅炉的安全稳定运行。通过系统分析生活垃圾和农林废弃物等固体燃料燃烧过程中可能的结焦、积灰和腐蚀形成机理,探讨了原料灰分组成和结焦、积灰、腐蚀形成的关联关系和预测方法,在此基础上比较了不同类型结焦、积灰和腐蚀抑制剂的作用机制及其施加效果,并对未来高效抑制剂的开发进行了展望。     

A critical review of ash slagging mechanisms and viscosity measurement for low-rank coal and bio-slags

Gasification or combustion of coal and biomass is the most important form of power generation today. However, the use of coal/biomass at high temperatures has an inherent problem related to the ash generated. The formation of ash leads to a problematic phenomenon called slagging. Slagging is the accumulation of molten ash on the walls of the furnace, gasifier, or boiler and is detrimental as it reduces the heat transfer rate, and the combustion/gasification rate of unburnt carbon, causes mechanical failure, high-temperature corrosion and on occasions, superheater explosions. To improve the gasifier/combustor facility, it is very important to understand the key ash properties, slag characteristics, viscosity and critical viscosity temperature. This paper reviews the content, compositions, and melting characteristics of ashes in differently ranked coal and biomass, and discusses the formation mechanism, characteristics, and structure of slag. In particular, this paper focuses on low-rank coal and biomass that have been receiving increased attention recently. Besides, it reviews the available methodologies and formulae for slag viscosity measurement/prediction and summarizes the current limitations and potential applications. Moreover, it discusses the slagging behavior of different ranks of coal and biomass by examining the applicability of the current viscosity measurement methods to these fuels, and the viscosity prediction models and factors that affect the slag viscosity. This review shows that the existing viscosity models and slagging indices can only satisfactorily predict the viscosity and slagging propensity of high-rank coals but cannot predict the slagging propensity and slag viscosity of low-rank coal, and especially biomass ashes, even if they are limited to a particular composition only. Thus, there is a critical need for the development of an index, or a model or even a measurement method, which can predict/measure the slagging propensity and slag viscosity correctly for all low-rank coal and biomass ashes.