烟气酸露点计算公式中过量空气系数的修正方法

烟气酸露点是锅炉运行及节能改造工程的重要参数之一,现有文献中计算酸露点的方法很多,但不同方法的计算结果差异较大。对文献中酸露点的计算方法进行了比较,在不同过量空气系数条件下,将现行公式计算烟气酸露点变化规律与实际相反原因进行了分析。对烟气酸露点计算公式中的过量空气系数进行修正,并给出了过量空气系数的修正公式。这一方法具有一定的应用价值。     

单元式露点蒸发冷却装置的实验研究

本研究设计了一台由干、湿通道相结合的单元式露点蒸发冷却装置,通过实验研究了蒸发冷却装置在空气经过一级冷却的模式1和经过二级冷却的模式2两种运行模式下,不同空气入口参数时的换热效果。实验结果表明,空气的入口温度越高,换热效果越好;低湿度时空气的进出口温差比高湿度时大,但其湿球效率和露点效率反而较低,这说明2种效率并不适用于不同湿度间的冷却效果对比;模式2运行时的换热效果比模式1好。与已有研究成果对比表明,该单元式露点蒸发冷却装置的湿球效率和露点效率分别可以达到120%和88%,为露点蒸发冷却装置的优化设计提供理论依据和优化方向。     

炼油装置加热炉节能途径与制约因素

加热炉是炼油装置的能耗大户,其节能水平对于提高炼油装置的节能水平具有重要意义。介绍了加热炉主要的节能途径：优化换热流程,降低加热炉热负荷;加热炉与其他设备联合回收余热;降低排烟温度、降低过剩空气系数、减少不完全燃烧损失、减少散热损失以提高加热炉热效率。探讨了上述节能途径的主要技术措施及应注意的问题。阐述了进一步提高加热炉节能水平的制约因素：降低排烟温度,要考虑经济性和露点腐蚀;过分降低炉外壁温度,会导致费用过高;预热空气温度过高对环保不利。提出了进一步提高加热炉节能水平的建议;认真净化燃料,降低露点温度;开发新的余热回收工艺;开发并应用“蓄热式高温空气预热贫氧燃烧技术”等新的燃烧技术;加强运行管理。     

燃气-蒸汽联合循环机组余热锅炉烟气酸露点温度计算

为了推进节能减排,在避免锅炉低温受热面腐蚀的前提下,进一步降低排烟温度,提高锅炉运行的安全性和经济性,对影响余热锅炉烟气酸露点的主要因素进行了分析,并通过对几种烟气酸露点温度计算方法的比较和评价,最终确定了适合燃气-蒸汽联合循环机组中余热锅炉烟气酸露点温度的计算方法及结果,并为日常运行中余热锅炉排烟温度的控制提供了依据。     

主控室应急可居留系统露点逐渐上升原因分析及解决措施

主控室应急可居留系统(VES)在核电站设计基准事故下具有为主控室人员提供可呼吸的清洁空气并阻止气载放射性物质进入主控室的功能,其中主要控制的化学指标有露点、CO、CO2、NO2、O2等.在实际运行过程中,出现VES系统露点随时间逐渐上升的趋势,并且经常接近监督试验要求的限值.通过对其进行原因分析排查并提出相应的解决措施...     

通信基站通风冷却节能系统的研究

绝大部分通信基站设备需一年四季运行空调,耗能巨大。为了减少基站能耗,可采用通风冷却节能系统部分替代空调系统。通风冷却系统对温湿度环境、露点温度、空气洁净度等方面具有特定要求。案例模拟分析结果表明:哈尔滨和北京地区尘降量过大,不适合使用通风冷却节能系统。而在未考虑尘降量的影响时,上海、广州和昆明的可使用时间分别为3949h、4089h、6082h,且该系统在昆明(温和区)的节电率最高,为65.56%。     

电站锅炉回转式空气预热器低温腐蚀研究

电厂燃煤含硫,易造成回转式空气预热器低温腐蚀。依据燃料工业分析得到的煤质成分计算出烟气中SO3浓度和酸露点温度,并依据SCR脱硝装置中SO2催化氧化转化率对酸露点温度进行修正。根据换热器传热计算原理计算出空气预热器冷段入口壁面平均温度和壁面最低温度,据此分析空气预热器的腐蚀情况,并调整配煤降低酸露点温度,保护空气预热器,提高锅炉效率,降低运行费用。     

新型无热再生干燥器在压缩空气系统中的应用

介绍压缩空气系统新型带露点控制的无热再生干燥器的特点,根据应用实例计算出节能效果.     

锅炉烟气酸露点温度计算及对预热器腐蚀的影响

锅炉烟气流经空气预热器时,当空气预热器金属壁温低于烟气酸露点温度时,即生成硫酸,从而导致空气预热器冷端腐蚀及堵灰。本文介绍了锅炉烟气酸露点温度的计算及对预热器冷端腐蚀的影响。     

延迟焦化装置空气预热器水热媒节能改造

克拉玛依石化公司150×104t/a延迟焦化装置加热炉热管空气预热器存在露点腐蚀和快速失效的问题,分析其原因和北方冬季严寒的天气条件有关:尽管烟气外排温度高于露点温度,但烟气侧底部热管管壁温度低于露点温度。对此,提出了采用水热媒技术的解决方案。实际改造过程中,为降低投资成本并满足除氧水系统压力的要求,采用了扰流子水热媒组合式空气预热器。改造完成后,烟气外排温度从改造前的234℃降低到152℃,降低了82℃;热空气温度从改造前的100℃升高到256℃,升高了156℃;热效率从改造前的87.35%提高到90.74%,提高了3.39个百分点;多回收烟气余热1901.31kW,每年节能54.76GJ,节约燃料费用121.3万元。该技术的成功应用,彻底解决了热管空气预热器存在的露点腐蚀和快速失效问题,可以保证装置长周期高效运行。     

Experimental study of gas humidification with injectors for automotive PEM fuel cell systems

A scaled gas humidification system using injectors for PEM fuel cell vehicles was developed and the humidification performance was evaluated under various operating conditions. The humidification system consists of an injector, a duplex enthalpy mixer and a water management apparatus. A dew point meter of the chilled mirror type was used to measure the humidity of the air and the hydrogen. Humidification performance was evaluated by measuring the dew point temperature of the humidified gases. Humidification performance was observed to be critically affected by the temperature of injected water and the gas flow rate in this study. The dew point of the humidified gas rose when the temperature of injected water increased, however, it dropped when the gas flow rate was increased. Experimental results show that the outlet temperature was 58.4 °C, dew point temperature of the humidified air reached 54.0 °C when the injection water temperature was 69.5 °C with the room temperature air flow rate of 200 L min⁻¹. Inlet gas temperature also affected the humidification performance and response time. In addition, a 50 cm² PEM fuel cell was tested to verify the effectiveness of the devised humidifier. When operated at 65 °C, the fuel cell showed an operating voltage of 0.5 V at a current density of 600 mA cm⁻².     

烟气酸露点温度的影响因素及其计算方法

确定烟气露点温度，已成为避免低温受热面造成腐蚀、增加锅炉运行安全性和提高锅炉效率的关键所在。文章对影响烟气酸露点的主要因素进行了分析，对几种烟气酸露点温度的计算方法进行了对比和评价，并依据酸露点的图表数据，拟合出烟气露点计算方程。     

The dew point temperature as a criterion for optimizing the operating conditions of proton exchange membrane fuel cells

In this article an analytical method to calculate the dew point temperatures of the anode and cathode exit gas streams of a proton exchange membrane fuel cell is developed. The results of these calculations are used to create diagrams that show the dew point temperatures as function of the operating pressure, the stoichiometric flow ratios and the net drag coefficient of water through the membrane. Then, computational modeling results obtained with a previously published model are analyzed and compared with the dew point charts, and it is demonstrated how cell flooding or membrane dry-out can be predicted a priori with the aid of these diagrams. Finally, guidelines for the desired cell operating temperature based on the expected dew point temperatures are developed. In the current work these guidelines are limited to the interdigitated flow field design, and they are likely to be different for conventional flow field plates. The diagrams presented here are created for completely dry inlet gases, but they can be easily corrected for a non-zero inlet relative humidity.     

Maisotsenko循环在燃气轮机进气冷却中的应用研究

采用基于Maisotsenko循环的露点间接蒸发式冷却作为进气冷却的手段,研究了不同环境条件下其对燃气轮机性能的提升效果。建立了针对某9E级燃气轮机的热力循环过程的计算模型,并利用该热力模型分析了进气温度变化对燃机出力的影响。基于Maisotsenko循环的原理,以温降为指标对露点间接蒸发冷却器的性能进行了分析。以功率和效率作为指标,对燃气轮机性能随环境条件的变化情况做了数值模拟,对露点蒸发式冷却与无进气冷却、直接喷雾式冷却对燃机性能的影响进行了计算分析。结果表明,在高温低湿度的条件下,露点间接蒸发式冷却能有效提升燃机性能。     

锅炉烟气露点温度计算方法比较分析

锅炉排烟温度低于烟气露点会引起低温腐蚀,影响锅炉安全运行。文章对计算烟气露点温度常用的图表法、估算公式法和经验公式进行了对比分析,并与实测数据进行比较,在此基础上提出了修正方法。     

Experimental evaluation of radiator control based on primary supply temperature for district heating substations

In this paper, we evaluate whether the primary supply temperature in district heating networks can be used to control radiator systems in buildings connected to district heating; with the purpose of increasing the ΔT. The primary supply temperature in district heating systems can mostly be described as a function of outdoor temperature; similarly, the radiator supply temperature in houses, offices and industries can also be described as a function of outdoor temperature. To calibrate the radiator control system to produce an ideally optimal radiator supply temperature that produces a maximized ΔT across the substation, the relationship between the primary supply temperature and outdoor temperature must be known. However, even if the relation is known there is always a deviation between the expected primary supply temperature and the actual temperature of the received distribution media. This deviation makes the radiator control system incapable of controlling the radiator supply temperature to a point that would generate a maximized ΔT.     

湿法脱硫除尘一体化装置应用中的问题及解决措施

从湿式脱硫系统运行参数和系统结构两个方面,论述了湿法脱硫除尘一体装置在工业化运行中存在的问题,指出pH值,露点温度的控制和脱硫装置有关部件的设计,是保证装置稳定高效运行的关键因素,并结合实践提出了改善和解决湿法脱硫存在问题的技术措施。