Studying the possibility and feasibility of shifting BKZ-420-140-NGM boilers for firing fuel in oxygen

Results from calculation studies of a BKZ-420-140-NGM boiler are presented, which showed the possibility of shifting it for firing natural gas in oxygen while retaining the design parameters of steam and ensuring reliable operation. Economic feasibility of making such a shift is estimated.     

Effect of combustion catalyst on the operation efficiency of steam boilers

The state of the energy market of the Ukraine is analyzed. The priority of using local, low-grade solid fuel according to its flame combustion in power boilers of thermal power plants and heat and power plants in the short-term perspective is proven. Data of expert tests of boilers of TPP-210A, BKZ-160-100, BKZ-210-140, Ep-670-140, and TGM-84 models with the investigation of the effect of the addition of combustion catalyst into primary air duct on their operation efficiency are represented. Positive results are attained by burning the anthracite culm or its mixture with lean coal in all range of operating loads of boilers investigated. The possibility to eliminate the consumption of “backlighting” high-reactive fuel (natural gas or fuel oil) and to operate at steam loads below the technical minimum in the case of burning nonproject coal is given. Problems of the normalization of liquid slag run-out without closing the boiler taphole are solved.     

Retrofitting the operating coal-fired TP-87 and BKZ-320 boilers for vortex fuel combustion technology

Scientific and technical problems concerned with retrofitting the TP-87 boiler installed at the Novokemerovo cogeneration station and operating on Grade 2SS Kuznetsk coal and the BKZ-320 boiler installed at the Novosibirsk TETs-3 cogeneration station and operating on Berezovo coal from the Kansk-Achinsk coal field for vortex combustion technology are addressed. A conclusion is drawn that low-cost retrofitting of obsolete boilers at thermal power stations with retaining the existing boiler unit infrastructure is presently the most reasonable strategy of their further use.     

300MW级供热机组采暖蒸汽凝结水回收系统探讨

近年来随着人们节能减排意识的加强,各种系统优化和节能措施逐渐提上研究日程。以节能减排为目的,以300 MW级热电联产工程为依托,以采暖蒸汽的凝结水为研究对象,进行设计优化。将300 MW级热电联产工程的采暖蒸汽凝结水回收系统进行了论述,通过详细对比各种回收方案的投资及经济效益,提出节能优化的推荐性意见,即供热首站热网蒸汽凝结水回水位置至6号低加出口。     

膜法半开式吸收式热泵回收烟气余热及水分系统特性分析

燃煤机组锅炉尾部烟气直接排放会造成大量的余热与水分损失。本文基于陶瓷膜管的选择透过性,利用溴化锂溶液的吸湿性,提出一种膜法半开式吸收式热泵系统,其中多通道陶瓷膜管吸收器吸收烟气中余热与水分,高温发生器、回热发生器及气液分离器实现溴化锂溶液的再生。以某330 MW燃煤机组锅炉为例,分析了不同循环工质参数、不同回热蒸汽流量以及吸收器内热交换量变化对膜法半开式吸收式热泵系统的影响。结果表明:溴化锂溶液的流量与溶液出口温度、脱水量呈正相关变化;吸收器内凝结水吸热量增大会提高脱水量,但会降低溶液出口温度;回热蒸汽流量变化会改变系统内各部分热量分布,增大回热蒸汽流量可以减少驱动热源热量,提高系统热回收性能,但存在限值。     

Thermal tests of the 9FB gas turbine unit produced by general electric

In July 2011, a PGU-410 combined-cycle power plant was commissioned at the Srendeuralsk district power station owned by Enel OGK-5. The main equipment of this power plant includes an MS9001FB gas turbine unit (produced by GE Energy Power Plant Systems, the United States), a heat recovery boiler (produced by Nooter/Ericsen, the United States), and a >Skoda KT-140-13.3 two-cylinder condensing and cogeneration turbine with steam reheating. In 2011–2012, specialists of the All-Russia Thermal Engineering Institute carried out thermal tests of this power plant in a wide range of loads and under different external conditions. The results from thermal tests of the MS9001FB gas turbine unit are presented and analyzed. The actual indicators of the gas turbine unit and its elements are determined and their characteristics are constructed.     

烟气深度冷却系统在1000 MW超超临界机组的应用

为了充分利用烟气余热加热凝结水,降低烟气温度,达到降低飞灰比电阻以提高电除尘器的除尘效率的目的,实现电除尘器“低温除尘增效”,同时提高锅炉效率,降低机组热耗和发电煤耗.在某1 000MW机组锅炉空气预热器出口与电除尘器入口烟道内设计、加装烟气余热利用回收装置.实践表明：加装烟气深度冷却装置后,电除尘器的除尘效率提高0.1％,脱硫水耗明显降低,机组供电煤耗显著下降.     

第一台出口海外国产600MW超临界锅炉技术特点分析

东方锅炉厂生产的DG1827/25.4 -Ⅱ4型锅炉是我国出口海外的第一台600 MW锅炉,安装在土耳其宗古尔达克省EREN电厂,这是我国超临界火力发电机组首次海外中标,与其它国产600 MW机组配套锅炉相比,在设计方面存在许多独到之处,并有很多技术特点值得分析研究.文中着重分析了锅炉在蒸汽参数选择、变压运行设计、螺旋...     

Technology used to operate the 300-MW power unit topped with a GTE-110 gas turbine

Results obtained from mathematical simulation of operations for starting the 300-MW power unit topped with a GTE-110 gas turbine installed at the GRES-24 district power station of OAO OGK-6 wholesale power-generating company are described. It is shown that operations on speeding up the steam turbine from a cold state to its idle running mode can be carried out solely by using the heat of exhaust gases from the gas turbine unit without supplying fuel to the boiler.     

Thermochemical recovery of heat contained in flue gases by means of bioethanol conversion

In the present paper consideration is being given to the use of bioethanol in the schemes of thermochemical recovery of heat contained in exit flue gases. Schematic diagrams illustrate the realization of thermochemical heat recovery by implementing ethanol steam conversion and conversion of ethanol by means of products of its complete combustion. The feasibility of attaining a high degree of recovery of heat contained in flue gases at the moderate temperature (up to 450°C) of combustion components is demonstrated in the example of the energy balance of the system for thermochemical heat recovery. The simplified thermodynamic analysis of the process of ethanol steam conversion was carried out in order to determine possible ranges of variation of process variables (temperature, pressure, composition) of a reaction mixture providing the efficient heat utilization. It was found that at the temperature above 600 K the degree of ethanol conversion is near unity. The equilibrium composition of products of reaction of ethanol steam conversion has been identified for different temperatures at which the process occurs at the ratio H₂O/EtOH = 1 and at the pressure of 0.1 MPa. The obtained results of calculation agree well with the experimental data.     

超临界机组试运期间水汽品质控制的探讨

从安装、化学清洗、吹管、整套试运、凝结水精处理运行、停炉保养等方面介绍兴义电厂1号机组在试运期间对水汽品质的控制。     

电站锅炉再热气温异常原因分级及解决方法

再热汽温异常是电站锅炉中较为普遍的现象。针对再热蒸汽压力低、比热容小、温度对吸热量变化敏感、再热蒸汽减温水量对机组经济性影响大的4个特点,分析了锅炉设计中再热器受热面为何采用负裕量布置和采用烟气侧调整手段调整再热汽温的原因,这也正是再热汽温易受煤种、燃烧方式、排汽温度等各种运行条件变化严重干扰的原因。对各种因素影响再热汽温的现象、规律、判定方法及相应对策进行了总结,强调了解决再热汽温问题先综合分析、再运行调整、然后进行受热面改造的顺序。针对再热器受热面改造的要求,总结了串联增加壁式再热器受热面、串联增加对流再热器和并联增加对流再热器受热面3种方式的优缺点,并指出并联增加对流再热器受热面具有更加明显的优势。可为分析和解决再热汽温问题提供全面借鉴经验。     

Investigation and optimization of the depth of flue gas heat recovery in surface heat exchangers

Economic issues associated with designing deep flue gas heat recovery units for natural gas-fired boilers are examined. The governing parameter affecting the performance and cost of surface-type condensing heat recovery heat exchangers is the heat transfer surface area. When firing natural gas, the heat recovery depth depends on the flue gas temperature at the condenser outlet and determines the amount of condensed water vapor. The effect of the outlet flue gas temperature in a heat recovery heat exchanger on the additionally recovered heat power is studied. A correlation has been derived enabling one to determine the best heat recovery depth (or the final cooling temperature) maximizing the anticipated reduced annual profit of a power enterprise from implementation of energy-saving measures. Results of optimization are presented for a surface-type condensing gas–air plate heat recovery heat exchanger for the climatic conditions and the economic situation in Tomsk. The predictions demonstrate that it is economically feasible to design similar heat recovery heat exchangers for a flue gas outlet temperature of 10°С. In this case, the payback period for the investment in the heat recovery heat exchanger will be 1.5 years. The effect of various factors on the optimal outlet flue gas temperature was analyzed. Most climatic, economical, or technological factors have a minor effect on the best outlet temperature, which remains between 5 and 20°С when varying the affecting factors. The derived correlation enables us to preliminary estimate the outlet (final) flue gas temperature that should be used in designing the heat transfer surface of a heat recovery heat exchanger for a gas-fired boiler as applied to the specific climatic conditions.     

Application of Condensing Heat Utilizers at Heat-Power Engineering Objects (Review)

Increasing the efficiency of fuel use in the production of electricity and heat can be achieved by carrying out activities aimed at modernizing existing power plants. Such highly effective measures include equipping boilers with a condensing heat utilizer (CHU) that allows the use of low-potential heat of outgoing flue gases. When the flue gases are cooled in CHU below the dew point temperature of the water vapor contained therein, up to 12–15% of the heat recovery can be obtained, which can be used to heat the return-network water in the heat network. It is most effective to use CHU in boilers burning natural gas and biofuel whose combustion products contain a large amount of water vapor. The temperature of the return-network water has a great influence on the efficiency of the CHU use. Three characteristic ranges of utilization efficiency of low-potential heat, which depends on the temperature of the reverse network water, are selected. Various solutions are given that allow ensuring a high degree of utilization in CHU of the heat released during condensation of water vapor contained in the combustion products at the temperature of the reverse-network water close to the dew-point temperature. Examples of the successful application of CHU of various brands at power plants in the Nordic countries, namely Sweden, Denmark, Latvia, and Estonia, that have similar climatic conditions with Russia and similar district heating systems are considered. CHU with preheating and humidification of air supplied to the boiler for combustion, which will not only effectively utilize low-potential heat but also significantly reduce emissions of nitrogen oxides into the atmosphere, are also considered.     

联合循环机组启动中凝汽器真空度下降的原因

介绍了M701F4型燃气-蒸汽联合循环机组冷态启动时,由于余热锅炉中积聚的大量不凝结气体不能及时排出而涌入凝汽器,造成凝汽器真空度下降的情况;建议在机组启动前对高、中、低压主汽管道及再热器系统有效抽排不凝结气体,启动过程中手动控制余热锅炉高、中、低压过热器出口和再热器出口对空排气阀的开启时间,以尽量排出各系统内的不凝结气体,避免机组启动过程中凝汽器真空度的过度下降。     

负荷分配对流化床-煤粉复合燃烧锅炉热力特性的影响

针对树皮流化床－煤粉复合燃烧锅炉的特点,提出了流化床按基本蒸汽负荷设计的思路。以７５ｔ／ｈ树皮流化床－煤粉复合燃烧锅炉为例,预测了总蒸汽负荷一定条件下,燃树皮产汽负荷与燃煤产汽负荷变化时锅炉的热力特性。计算表明,随着燃树皮产汽负荷的增加,煤粉炉膛的绝热燃烧温度和流化床温度降低;而炉膛出口烟温、排烟温度、空气预热器出口风温和高温风风量、减温水量等热力参数升高,但变化幅度不大,证明了前述设计思路的可行性。在一定的基本蒸汽负荷下,燃树皮产汽负荷的上限值可根据流化床中树皮的稳定燃烧温度和减温系统的工作能力来确定。     

热电厂热经济性指标分析实证研究

通过对热电厂不同供热工况的分析与判断，发现存在的问题，提出改进的措施。结合具体企业的实例进行热经济性指标分析与研究，得出该企业运行的供热抽汽参数工况与设定的低参数工况接近，其中压机组凝汽发电部分的热耗高，供热、供电标准煤耗率高，汽轮机选型不够合理等结论。并为该企业提出了尽量使用煤粉炉，减少低效率的链条炉运行，降低对外供汽参数，在最小凝汽量下运行等降低供热、供电标准煤耗率的途径。     

复水冷却滚筒冷渣器在DG 450 t/h CFB锅炉中的应用

针对国内大型循环流化床锅炉冷渣器堵塞、排渣不畅而制约机组稳定运行的突出问题,结合现场实际情况,在滚筒冷渣器大多采用化学除盐水作为冷却水源的基础上,将汽轮机复水作为冷却用水应用于生产实际,彻底解决了锅炉排渣堵塞和炉渣热量回收利用问题。     

Use of coals for cocombustion with Estonian shale oil

The article reports the results of investigation into the possibility of using off-design coals as an additional fuel in connection with predicted reduction in the heat of combustion of shale oil and more stringent environmental regulations on harmful emissions. For this purpose, a mathematical model of a TP-101 boiler at the Estonian Power Plant has been constructed and verified; the model describes the boiler’s current state. On the basis of the process flow chart, the experience of operating the boiler, the relevant regulations, and the environmental requirement criteria for evaluation of the equipment operation in terms of reliability, efficiency, and environmental safety have been developed. These criteria underlie the analysis of the calculated operating parameters of the boiler and the boiler plant as a whole upon combustion with various shale-oil-to-coal ratios. The computational study shows that, at the minimal load, the normal operation of the boiler is ensured almost within the entire range of the parts by the heat rate of coal. With the decreasing load on the boiler, the normal equipment operation region narrows. The basic limitation factors are the temperature of the steam in the superheater, the temperature of the combustion products at the furnace outlet and the flow rate of the combustion air and flue gases. As a result, the parts by heat rate of lignite and bituminous coal have been determined that ensure reliable and efficient operation of the equipment. The efficiency of the boiler with the recommended lignite-to-coal ratio is higher than that achieved when burning the design shale oil. Based on the evaluation of the environmental performance of the boiler, the necessary additional measures to reduce emissions of harmful substances into the atmosphere have been determined.     

南昌电厂锅炉飞灰磨损的治理

针对南昌电厂420t/h锅炉存在汽温偏低、飞灰磨损严重的问题,进行了热力计算和冷态空气速度场测试试验(CAVT),提出了燃烧器上摆、敷设远红外卫燃带、改变配风与送粉方式、加装均流屏筛等改造措施,使锅炉运行可靠性大大提高。