燃煤电站烟气水分回收技术试验研究

为改善锅炉效率并回收水分,利用加湿天然气烟气模拟褐煤锅炉排烟,通过布置在水平烟道中的错列光管水冷换热器进行冷凝换热,研究入口烟温维持在50℃～60℃时,烟气流速(3～8 m/s)、烟气中水蒸汽容积份额(4%～14%)、冷却水流量及流动方式等因素对高水蒸汽含量烟气冷凝液捕集率的影响,提出适用于电站的水分处理及回收利用技术...     

燃煤机组烟气余热及水协同回收系统结构参数优化研究

为了提高燃煤发电机组效率、降低机组水耗,本文针对烟气余热及水协同回收系统展开研究.该系统通过烟气换热器降低烟气温度至95℃,回收低温烟气余热的同时降低脱硫塔耗水量,并通过烟气冷凝器回收烟气中的水分,实现节能与节水的协同.本文研究了系统的运行特性,发现其有良好的节能节水潜力,同时研究了系统换热器面积及冷凝水质量流量对系统运行参数及性能的影响,发现低温省煤器、烟气冷却器、烟气再热器面积和低温省煤器冷凝水质量流量降低可以提高进入电除尘器烟气温度,为系统变工况运行调控、防止低温腐蚀提供指导.     

锅炉烟气余热回收效益明显

介绍锅炉房使用的6t/h燃煤蒸汽锅炉,原来排烟温度220℃左右,对老式省煤器进行改造,利用EC型锅炉余热回收器,最后使排烟温度降至50℃左右。既改善了引风风机的工况条件,又回收了大量的热能,使一般燃煤锅炉的效率有了明显的上升。     

烟气余热二次回收节能效果探究

以某电厂实际660 MW机组为研究对象,探究了增设烟气二级余热回收系统的经济性.从计算结果来看,提出的二级余热回收方案,在考虑辅机能耗后,能够使得供电标准煤耗率降低量为0.088 g/kWh,具有良好的可实施性,但经济效益不高,回收周期为4.5年.     

燃煤烟气冷凝节水及余热回收热力学分析

针对燃煤电站锅炉采用湿法烟气脱硫技术后,如直接将饱和湿烟气排向环境会产生湿烟羽的问题,建立湿烟羽数学模型,分析了烟气降温冷凝过程对脱硫塔进出口烟气余热以及水量回收的影响。结果表明：采用低温省煤器回收脱硫塔进口部分余热,当烟温由130℃降至90℃,可回收热量21.477 MW;采用烟气冷凝消白,当环境相对湿度为10%,环境温度为-20℃时,可回收冷凝水量144.215 t/h,回收烟气余热109.603 MW,且随环境温度的升高,回收冷凝水量和烟气余热量逐渐减少;不同煤质对烟气冷凝节水及余热回收影响不同。     

大型燃煤电站锅炉典型烟气余热回收系统的性能分析

增设烟气余热回收系统是大型燃煤电站锅炉节能的有效途径.分析比较了4种典型锅炉尾部烟气余热回收系统,并结合某200MW机组参数,应用等效焓降理论及节能定量分析理论计算、比较了各种余热回收系统的经济性.分析结果表明,普通低压省煤器余热回收系统节能量最大,复合相变换热器余热回收系统性价比较高.     

电站锅炉新型烟气余热回收技术及经济性分析

为解决某300 MW火力发电厂循环流化床锅炉排烟温度偏高的问题,提出将传统低压省煤器与卧式相变换热器相结合的新型烟气余热回收技术.该技术不仅能预防换热设备酸腐蚀,还能实现电厂烟气深度余热回收节能.给出了系统的具体布置方案和设计参数,分析了系统对凝汽器真空以及引风机性能的影响,并应用等效焓降理论及节能定量分析理论进行理论计算.计算结果表明,采用该系统后,锅炉排烟温度降低45℃,降低标准煤耗近3.5 g/（kW·h）.     

Techno‐economic comparison of boiler cold‐end flue gas heat recovery processes for efficient hard‐coal‐fired power generation

An important method to increase the efficiency of thermal power plants is to recover the exhaust gas heat at the boiler cold‐end with the stepwise integration of a steam turbine heat regenerative system. To this end, there are currently three typical heat recovery processes, that is, a low‐temperature economizer (LTE), segmented air heating (SAH) and bypass flue (BPF). To provide useful guidance to thermal power plants for optimal and efficient processes, the thermal economy and techno‐economic performance of the three aforementioned processes were calculated and compared using an in‐service 600‐MW hard‐coal‐fired ultra‐supercritical power unit as a reference. The results demonstrate that with the use of the LTE, SAH and BPF, respectively, to recover the exhaust heat, reducing the exhaust temperature from 122 °C to 90 °C, the net standard coal consumption rate of the 600‐MW unit can be reduced by 1.51, 1.71 and 2.81 g/(kW h). The initial costs of the three heat recovery projects are 1.69, 2.91 and 2.53 million USD. If the 600‐MW unit runs 5500 h per year at the rated load, the three processes can increase the earnings of the unit by 0.49, 0.52 and 0.94 million USD from coal savings annually, meaning that their dynamic payback periods are 4.42, 8.66 and 3.29 years, respectively. The results indicate that for a hard‐coal‐fired power unit, the coal savings achieved by exhaust heat recovery are notable. Among the three processes, SAH shows the worst techno‐economic performance because it induces a significant increase in initial costs while obtaining a limited increase in thermal economy, while BPF exhibits the best techno‐economic performance owing to the significant increase in thermal economy. Copyright © 2016 John Wiley & Sons, Ltd.     

径向热管换热器在天然气工业炉低温烟气中的应用

当前我国的能源形势紧张,能源利用状况令人担忧.在一些高耗能的企业,工业生产中排放的中低温烟气余热由于回收难度高、回收成本大等问题,一直得不到合理的利用,如何合理回收成为亟待解决的难题之一.简要介绍了一种新型余热利用换热设备——径向热管换热器,提出了计算热管换热器经济性评价指标的方法,并以某工厂低温烟气余热回收工程为实例,对烟气余热的回收利用进行了技术和经济效益分析.实践应用证明,径向热管换热器在工业低温烟气余热回收中有很好的实用性和可行性.     

An Experimental Study on Latent Heat Recovery of Exhaust Wet Flue Gas

The experiment was conducted to investigate the heat transfer performance of wet flue gas in a vertical tube. The factors influencing the convective condensation of wet flue gas were experimentally investigated. The measured results indicate that the convective heat transfer of bulk flow and condensation heat transfer of vapor have significant contribution to the total heat transfer and the dominant transport mechanism is dependent upon the vapor fraction in mixture.     

中小型燃煤电厂烟气脱硫改造工艺技术路线的确定

结合某中小型燃煤电厂脱硫改造工程需要,分析了几种常用的烟气脱硫工艺技术,确定半千法为本工程烟气脱硫改造用工艺。同时通过对国内几种常见半干法工艺方案分析、比较,最终确定烟气循环流化床脱硫技术为本工程脱硫改造方案。     

火电厂低温余热利用技术应用分析

综述火电厂低温余热利用技术的特点及应用现状,并对各种技术进行了对比分析,其中集中式吸收式热泵供热技术在当前应用最广泛,是最具发展前景的技术。苇湖梁电厂低温余热利用项目是集中式吸收式热泵125MW水冷机组技术在国内的首次工程应用,项目具有显著的节能效果,可实现年节约标煤41688t,节水65.88万t。     

垃圾焚烧电厂热电联产的经济性分析

合理利用垃圾资源进行热电联产,是节能减排、改善环境的有力措施。以某2×750 t·d^-1垃圾焚烧电厂为例,通过模型研究发现热电联产可以减少垃圾焚烧电厂的冷源损失,提高全厂热效率;利用一抽蒸汽进行热电联产可实现蒸汽品质的梯级利用,获得较高的经济效益;供热量为30 t·h^-1,垃圾热值由4185.9 kJ·kg^-1增加至8371.7 kJ·kg^-1时,发电量越多,供热能力越强,年热电联产经济效益由7822.76万元增加到14641.07万元;垃圾热值为8371.7 kJ·kg^-1,供热量从10 t·h^-1增加到60 t·h^-1时,垃圾焚烧电厂热效率从28.96%增加到48.50%,年经济效益从13602.74万元增加到15455.66万元。当该地区垃圾热值较高并具备供热条件时,实现垃圾热电联产具有较高的收益。     

垃圾焚烧烟气余热利用的探讨

从利用烟气干燥物料的角度对干燥过程的认识、焚烧烟气的组成、烟气流动动力、烟气干燥模型、新型焚烧炉的特点、烟气温度的衡算等方面作了些分析与探讨。这对中小型焚烧炉烟气余热回收利用及其它工业炉降耗增效都具有一定的意义。     

Thermodynamic analysis of an LNG fuelled combined cycle power plant with waste heat recovery and utilization system

This paper has proposed an improved liquefied natural gas (LNG) fuelled combined cycle power plant with a waste heat recovery and utilization system. The proposed combined cycle, which provides power outputs and thermal energy, consists of the gas/steam combined cycle, the subsystem utilizing the latent heat of spent steam from the steam turbine to vaporize LNG, the subsystem that recovers both the sensible heat and the latent heat of water vapour in the exhaust gas from the heat recovery steam generator (HRSG) by installing a condensing heat exchanger, and the HRSG waste heat utilization subsystem. The conventional combined cycle and the proposed combined cycle are modelled, considering mass, energy and exergy balances for every component and both energy and exergy analyses are conducted. Parametric analyses are performed for the proposed combined cycle to evaluate the effects of several factors, such as the gas turbine inlet temperature (TIT), the condenser pressure, the pinch point temperature difference of the condensing heat exchanger and the fuel gas heating temperature on the performance of the proposed combined cycle through simulation calculations. The results show that the net electrical efficiency and the exergy efficiency of the proposed combined cycle can be increased by 1.6 and 2.84% than those of the conventional combined cycle, respectively. The heat recovery per kg of flue gas is equal to 86.27 kJ s^?1. One MW of electric power for operating sea water pumps can be saved. The net electrical efficiency and the heat recovery ratio increase as the condenser pressure decreases. The higher heat recovery from the HRSG exit flue gas is achieved at higher gas TIT and at lower pinch point temperature of the condensing heat exchanger. Copyright © 2006 John Wiley & Sons, Ltd.     

锅炉燃烧优化控制系统在火电厂的应用

针对某电厂330 MW机组锅炉上实施燃烧优化闭环控制系统项目,总结燃烧优化项目成功实施的几个重要步骤及实施中应该注意的问题,为此类项目在国内实施提供经验借鉴。     

燃煤电厂烟气中的汞浓度测量

综述了燃煤电厂烟气中各种形态汞浓度的测量方法,并对各方法的优缺点进行比较.重点介绍美国环境保护署（EPA）推荐的安大略方法（Ontario Hydro Method,简称OHM）.该方法采用等速取样、加热和防止吸附的手段,具有真实样品的代表性和准确性;采用汞的冷蒸气原子吸收原理分析汞的浓度,因而精度较高;被美国EPA和能源部（DOE）等机构推荐为美国的汞标准测试和分析方法.同时指出在中国燃煤电站采用OHM法结合汞连续在线监SCEM（Semi-Continuous Emission Monitor）法进行烟气中汞浓度现场测试和分析的实际意义.