第二代PFBC—CC中试电站初步方案及性能分析

第二代PFBC-CC联合循环发电系统是目前具有发展前景的洁净煤发电技术之一,本文以徐州贾汪PFBC-CC中试电站为基础,拟定了第二代PFBC-CC发电系统的基本流程,并对系统中几个主要参数进行了性能分析,提出了一较为合理并适合现场改造的第二代PFBC-CC中试电站系统的初步方案。     

NIT增压流化床燃烧(PFBC)试验研究

增压流化床燃烧(PFBC)技术是实现燃煤联合循环发电的主要技术途径之一.本文叙述了NIT增压流化床燃烧装置和它的启动运行,以及试验研究的初步结果.在燃用高灰煤时,燃烧效率达98％,燃气通过高温除尘系统后含尘量为189毫克/标米~3,颗粒平均粒度2.5—3.0微米,其中大于12微米的不超过3％.     

捕获CO2的部分煤气化氢电联产系统

基于煤炭分级转化、成分对口应用、污染物控制一体化等系统集成思路,提出了一种捕获CO₂的部分煤气化氢电联产系统。该系统利用增压流化床完成煤炭部分气化,降低了气化难度与气化炉造价,具有较好经济性;全面揭示了系统的热力和环境特性规律,指出气化炉碳转化率是影响系统热力性能的主要因素;系统具有良好的热力特性与环境特性,当CO₂的分离率为59.7%时,系统（火用）效率为54.3%。本文的研究为煤炭的清洁高效利用提供了可选择的途径。     

PFBC/CCTE系统热力参数优化及其特性分析

增压流化床燃气-蒸汽联合循环总能系统(下文简称PFBC/CCTE系统)是一种高效低污染的新型燃煤发电装置.鉴于国内目前燃气透平的进汽温度较低,经比较PFBC/CCTE系统效率优于煤气化CCTE系统.为此这里仅对PFBC/CCTE系统(火用)效率影响的主要因素进行简要分析,以媚效率为目标函数对该系统进行参数优化.结合国内电厂     

振动流化床冷渣器试验研究

本文提出了冷却高温炉渣的振动流化床技术，研制了集连续可控排放和冷却于一体的新型冷渣器工业装置．采用物理性质相异法较系统地研究了冷渣器内宽筛分物料的停留时间分布．对气固两相流的空气动力学特性和热态运行工况进行了试验研究和理论分析．结果表明，在风渣比为1．5～2．5Nm3／kg时，冷渣器的热回收率达到85％以上．     

焦载热气化燃煤联合循环系统的数学模型研究

１焦载热燃煤联合循环系统简介中国能源工业以煤炭为主的格局,决定了能源发展及可持续发展战略必须立足于“煤的高效及清洁燃烧技术”。在这一方面,燃煤的联合循环技术最具潜力;它能大幅度地提高发电厂的热效率,并使污染问题得到解决。清华大学近年来一直致力于这方面的工作。１９９２年,清华大学申报了差速循环流化床和飞灰造粒回燃两项专利,同时对载热气化技术进行了深入地研究。在以上工作基础上,提出了一种易于实现的新型燃煤联合循环发电技术：载热部分气化联合循环技术,并于同年申报了专利。该系统［１－２］采用高温颗粒流动…     

高负荷后掠风扇设计若干基本问题

1单级风扇ATS－2（Ad、ncedTransonicStage）设计概述目的是探索总增压比为4．3的两级风扇的设计技术。指标为：设计后掠风扇进口级的缩尺实验件;级增压比2．2;级绝热效率不小于85％;喘振裕度不小于12％。取进口级增压比为2．2,意味着这类单级的增压比已超过大多数于50～80年代设计并服役的涡喷、涡扇发动机前两级轴流级的总增压比,例如WP7发动机。这就需要选用更高的叶尖线速度（相对来流马赫数）。于是这类高性能跨音级的技术特征为级压比高,线速度高,单位迎面流量大,转子叶片后掠或前掠。这时效率的维持主要受到两方面的制约…     

免疫亲和柱HPLC荧光检测酒中黄曲霉毒素B1、B2、G1、G2

采用单隆抗体免疫样和技术作为直接从样品分离提纯黄曲霉素素的特效手段,提出液挥发干后,经衍生用HPLC荧光检测器测定,本法在样品中添加2．5μg/kg黄曲霉素素时进行10次测定,平均回收率分别为G178．3％、B197．3％、G261．7％、B290．5％;2．5μg/kg10次测定的精密度分别为：G4．50％、B13．805、G23．68％、B24．77％,本方法在25－1250pg范围内呈线性,相关系数分别为G1：r=0.9990,B1:r=0.9994,G2:r=0.9995,B2:r=0.9992 ,测定的最低检出限为6．25pg.     

PFBC/CC燃机叶片的腐蚀/冲蚀机理研究

一、引言 增压流化床燃烧燃气/蒸汽联合循环(PFBC/CC)发电技术中关键问题之一,是燃机叶片的腐蚀和冲蚀。PFBC出口烟气是腐蚀性的含尘气流,叶片受到腐蚀/冲蚀的复合作用,不仅会使叶型变化,叶栅压损增加,降低燃机效率,而且会使动叶强度降低,寿命缩短,威胁机组安全。本文综合了前人的研究成果,就腐蚀机理作了探讨,并着重就冲蚀现象进行了冷态试验研究,得到了一些有用的结论。     

多组分粒子流化床半湿式烟气脱硫基础研究

本文提出了一种新型的应用多组分粒子流化床（MSFB）的半湿式烟气脱硫方法．在本研究阶段，对多组分粒子流化床的粒子流动特性、浆液的干燥特性、采用模拟烟气时的脱硫效率等进行了初步探讨，得到如下结果。（1）大、小粒子混合流化时，小粒子达到输送状态的时间有所延迟，稳定操作速度主要由大粒子的流化特性决定；（2）浆液的完整干燥过程分下落和床内两个阶段。浆液在床内的干燥过程中产生的蒸汽使粒子流化床膨胀，床层阻力下降；（3）采用CaCO3时，脱硫率可达80％以上．     

Simulation of a full-scale pressurized fluidized bed combustor by using semi-empirical pilot plant correlations

A model, based on semi-empirical correlations, was developed to simulate the behavior of a pressurized fluidized bed combustor (PFBC) under various operating conditions. This paper presents the results of a comprehensive survey of one-dimensional empirical correlations applicable to a PFBC and which were used to assemble a 1-D predictive model of the complete performance of a pressurized fluidized bed combustor. The model was adjusted in order to reproduce process and in-bed data taken at Escatrón PFBC power station (Spain) under a wide range of operating conditions. The novelty of this approach lies in the use of full-scale information to validate empirical correlations, the objective being to draw specific conclusions on the reliability of empirical PFBC modeling. The model was validated using experimental power plant data. Good agreement was found between the computed results and actual plant data of bed temperature profiles, bed density, char and sorbent elutriation, fuel feed rate, in-bed and entrainment particle size distributions, oxygen and carbon dioxide concentrations, heat transfer coefficients along the combustor height and heat transfer to the tube bundles under different operational regimes. This paper describes the model, as well as its results, validation and prospects for future work.     

城市垃圾与煤混烧的灰渣中重金属的特性分析

在0.15MWt循环流化床燃烧试验台上进行了城市垃圾与煤混烧试验,对焚烧后的灰渣中重金属的特性进行了研究。研究结果显示,重金属在焚烧产物中通常以不同的化合物形态存在,改变垃圾与煤混烧时的燃烧工况条件,可以改变重金属的化合物形态,从而改变重金属在灰渣中的分布;灰渣中重金属的浸出毒性低于危险废物浸出毒性鉴别标准中的限定值。     

Oxy-coal combustion in a 30 kWth pressurized fluidized bed: Effect of combustion pressure on combustion performance,pollutant emissions and desulfurization

Oxy-coal combustion with pressurized fluidized beds has recently emerged as a promising carbon capture and storage (CCS) technology for coal-fired power plants. Although a large number of energy efficiency analyses have shown that an increase in combustion pressure can further increase the net plant efficiency, there are few experimental studies of pressurized oxy-coal combustion conducted on fluidized bed combustors/boilers with continuous coal feeding. In this study, oxy-coal combustion experiments with lignite and anthracite were conducted with a 30 kW_th pressurized fluidized bed combustor within the pressure range of 0.1 MPa to 0.4 MPa. The investigation focused on the elucidation of the impacts of combustion pressure on the combustion performance, pollutant emissions and desulfurization of oxy-coal combustion in fluidized beds. The results showed that an increase in pressure increased the combustion efficiency and combustion rate of coal particles, and the promoting effect of pressure increase was more significant for the high rank coal with smaller particle size and the high O₂ concentration atmosphere. For both coals, NO_x emissions decreased with pressure but N₂O emissions increased with pressure and accounted for a considerable part of the nitrogen oxide pollutants under high pressure oxy-coal combustion conditions. The pressure had insignificant impact on the SO₂ emissions of oxy-coal combustion but an increase in pressure enhanced the direct desulfurization of limestone.     

生物质洁净能源研究中的流化床动力学模型

分别对最小流化床、鼓泡流化床和腾涌流化床及相应的全混模型、鼓泡模型、气泡汇集模型等加以综述 ,分析其优缺点 ,并在此基础上提出动力学模拟研究的新思路 .根据流化床内在的本质———流化态的不同 ,将流化床分为最小流化床、鼓泡流化床和腾涌流化床三种 .总结了前人针对各种流化床提出的全混模型、鼓泡模型、气泡汇集模型等思想 ,建议今后可以在以下几个方面进行深入研究 :⑴使得模型更有普适性 .⑵由于气泡有效直径尚不能在理论上求得 ,可以在理想气泡直径变化公式的基础上 ,加入非线性化学的计算 .⑶确定不同情况下的参数 ,使得工作更有延续性 ,也使得模型更加具有生命力 .⑷从高压的角度去进行模型的计算 ,并得到相应的试验数据支持 .     

小麦秸秆流态化燃烧粘结特性实验研究

在5 kW鼓泡流化床实验装置上,利用床层压差和温度的变化作为判断床层粘结失流的依据,以小麦秸秆成型颗粒作为研究对象,进行了燃烧温度、床料粒径和流化风速对失流时间影响的实验研究。实验结果表明:失流时间随着燃烧温度上升而缩短;流化风速增大,失流时间增长;床料粒径对失流时间影响不明显。对粘结物进行了SEM/EDX和XRF分析,分析结果表明,Si和K元素形成的熔融物对床料的粘结起重要的作用。     

城市下水污泥和煤/LPG在循环流化床上的混烧试验研究

在高6000 mm、直径300mm的循环流化床上进行了含水率为79％的湿污泥与煤／石油液化气(LPG)的混烧试验。试验结果表明:无论用煤还是LPG作为辅助燃料,试验都能在设定的工况条件下稳定运行;向炉内加入石灰石的量达到钙硫摩尔比为3．4∶1时,二氧化硫和氯化氢的排放达标,脱硫效率和脱氯效率分别为75％和94％;在试验中, 烟气中NOx排放、烟气中汞含量和二恶英类排放都不超标;试验产生的飞灰含碳量低,飞灰中痕量元素的浸出毒性不超标;计算表明,如果利用余热干燥污泥和预热空气可有效地减少辅助燃料的消耗量。     

Mercury removal from aqueous solution and flue gas by adsorption on activated carbon fibres

The use of two activated carbon fibres, one laboratorial sample prepared from a commercial acrylic textile fibre and one commercial sample of Kynol^®, as prepared/received and modified by reaction with powdered sulfur and H₂S gas in order to increase the sulfur content were studied for the removal of mercury from aqueous solution and from flue gases from a fluidized bed combustor. The sulfur introduced ranged from 1 to 6 wt.% depending on the method used. The most important parameter for the mercury uptake is the type of sulfur introduced rather than the total amount and it was found that the H₂S treatment of ACF leads to samples with the highest mercury uptake, despite the lower sulfur amount introduced. The modified samples by both methods can remove HgCl₂ from aqueous solutions at pH 6 within the range 290-710 mg/g (ACF) which can be favourably compared with other studies already published. The use of a filter made with an activated carbon fibre modified by powdered sulfur totally removed the mercury species present in the flue gases produced by combustion of fossil fuel.     

Pressurized oxy-fuel combustion of a char particle in the fluidized bed combustor

Pressurized oxy-fuel combustion of coal in fluidized bed (FB) holds the potential to realize low-cost CO₂ capture. However, the fundamental study in this manner is still rare due to the difficult access to the pressurized oxy-FB combustion tests. In this work, the experimental study of single char combustion was firstly conducted in a visualized pressurized FB combustor under various operating conditions. Then an experimentally verified particle-scale char combustion model was developed to reveal the dependence of char combustion on parameters. Results showed that the char conversion was accelerated with the increase of pressure, mainly due to the high oxygen diffusion and char gasification. The gasification played a non-negligible role in pressurized oxy-fuel combustion, especially under high oxygen concentration and bed temperature. Increasing oxygen concentration and bed temperature not only promotes the char oxidation rate and particle temperature, but also increases the gasification rate and the share of char conversion via gasification, resulting in shortening the burnout time of char. In addition, a higher fluidization number lowered both the burnout time and peak temperature of char particle, due to the simultaneous improvement of mass and heat transfer. The influences of char size and fluidization number on char gasification conversion ratio are very weak. In addition, the quantitative analysis of the influence of different operating parameters on the combustion process was obtained by model sensitivity analysis.     

热烟气启动流化床的数学模型

1引言在流化床锅炉能够正常运行之前，必须进行点火操作，把惰性床料流化加热到足够高的温度，以使燃料能够开始燃烧。用高温热烟气经由布风板加热床层，传热效率较高，易于实现自动控制，能够明显缩短启动时间，减少辅助燃料消耗，目前国外普遍采用这种方法山。在我国第一台中试PFBC锅炉的启动中，就将采用热烟气启动的方式。为了对热烟气启动增压流化床进行模拟研究，提出了一种热烟气启动流化床的简化模型二本文提出的简化模型，考虑了扬析、磨损等因素，力求物理概念正确、简单实用、功能强；特别是借鉴对于间隙扬析过程的处理方法，…