Experimental Study on Ammonia Co-Firing with Coal for Carbon Reduction in the Boiler of a 300-MW Coal-Fired Power Station

To reduce CO_(2) emissions from coal-fired power plants,the development of low-carbon or carbon-free fuel combustion technologies has become urgent.As a new zero-carbon fuel,ammonia(NH_(3))can be used to address the storage and transportation issues of hydrogen energy.Since it is not feasible to completely replace coal with ammonia in the short term,the development of ammonia-coal co-combustion technology at the current stage is a fast and feasible approach to reduce CO_(2) emissions from coal-fired power plants.This study focuses on modifying the boiler and installing two layers of eight pure-ammonia burners in a 300-MW coal-fired power plant to achieve ammonia-coal co-combustion at proportions ranging from 20%to 10%(by heat ratio)at loads of 180-to 300-MW,respectively.The results show that,during ammonia-coal co-combustion in a 300-MW coal-fired power plant,there was a more significant change in NO_(x) emissions at the furnace outlet compared with that under pure-coal combustion as the boiler oxygen levels varied.Moreover,ammonia burners located in the middle part of the main combustion zone exhibited a better high-temperature reduction performance than those located in the upper part of the main combustion zone.Under all ammonia co-combustion conditions,the NH_(3) concentration at the furnace outlet remained below 1 parts per million(ppm).Compared with that under pure-coal conditions,the thermal efficiency of the boiler slightly decreased(by 0.12%-0.38%)under different loads when ammonia co-combustion reached 15 t·h^(-1).Ammonia co-combustion in coal-fired power plants is a potentially feasible technology route for carbon reduction.

Optimizing Two-Phase Flow Heat Transfer:DCS Hybrid Modeling and Automation in Coal-Fired Power Plant Boilers

In response to escalating challenges in energy conservation and emission reduction,this study delves into the complexities of heat transfer in two-phase flows and adjustments to combustion processes within coal-fired boilers.Utilizing a fusion of hybrid modeling and automation technologies,we develop soft measurement models for key combustion parameters,such as the net calorific value of coal,flue gas oxygen content,and fly ash carbon content,within theDistributedControl System(DCS).Validated with performance test data,thesemodels exhibit controlled root mean square error(RMSE)and maximum absolute error(MAXE)values,both within the range of 0.203.Integrated into their respective automatic control systems,thesemodels optimize two-phase flow heat transfer,finetune combustion conditions,and mitigate incomplete combustion.Furthermore,this paper conducts an in-depth exploration of the generationmechanismof nitrogen oxides(NOx)and low oxygen emission reduction technology in coal-fired boilers,demonstrating a substantial reduction in furnace exit NOx generation by 30%to 40%and the power supply coal consumption decreased by 1.62 g/(kW h).The research outcomes highlight the model’s rapid responsiveness,enabling prompt reflection of transient variations in various economic indicator parameters.This provides a more effective means for real-time monitoring of crucial variables in coal-fired boilers and facilitates timely combustion adjustments,underscoring notable achievements in boiler combustion.The research not only provides valuable and practical insights into the intricacies of two-phase flow heat transfer and heat exchange but also establishes a pioneering methodology for tackling industry challenges.

Xiangfan Coal-fired Power Plant - a matched large power plant for Three Gorges Project starts to construct

Xiangfan Coal-fired Power Plant, a key energy construction project matched with Three Gorges Project, approved by the State Council. formally started to build in the suburb of Xiangfan City, Hubei Province on November 29, 1996.

Analysis of Prese nt Operating Situati on of Large Size Coal-F ired Utility Boilers

Large size utility boilers develop rapidly in China, both their reliability and economics have reached better level. The operating situations of various existing boilers on the basis of different coals are analyzed, it is held that, the notable energy imbalance of furnace exit, ever existing in the tangential firing boilers has been solved, with comparatively lower NOX emission concentration of gained. The higher NOX emission concentration and furnace slagging etc. problems existing in wall firing boilers are notable. The comprehensive analysis shows that, it is appropriate to choose lower furnace volume heat release rate and higher flame height in the type selection design of boilers, and sufficient margin should be kept in the selection of coal pulverizing mills.

INTRODUCTION TO INCONEL ALLOY 740: AN ALLOY DESIGNED FOR SUPERHEATER TUBING IN COAL-FIRED ULTRA SUPERCRITICAL BOILERS

Chinese utilities as well as those worldwide are facing increased demand for additional electricity, reduced plant emissions and greater efficiency. To meet this challenge will require increasing boiler temperature, pressure and coal ash corrosion resistance of the materials of boiler construction of future coal-fired boilers. A new nickel-based tube alloy, INCONEL^R alloy 740, is described aiming at meeting this challenge. Emphasis will be on describing the alloy＇ s mechanical properties, coal-ash and steam corrosion resistance. Microstructural stability as a function of temperature and time is addressed as well as some of the early methodology em- ployed to arrive at the current chemical composition.

NO_x emission model for coal-fired boilers using partial least squares and extreme learning machine

To implement a real-time reduction in NOx,a rapid and accurate model is required.A PLS-ELM model based on the combination of partial least squares(PLS)and the extreme learning machine(ELM)for the establishment of the NOx emission model of utility boilers is proposed.First,the initial input variables of the NOx emission model are determined according to the mechanism analysis.Then,the initial input data is extracted by PLS.Finally,the extracted information is used as the input of the ELM model.A large amount of real data was obtained from the distributed control system(DCS)historical database of a 1 000 MW power plant boiler to train and validate the PLS-ELM model.The modeling performance of the PLS-ELM was compared with that of the back propagation(BP)neural network,support vector machine(SVM)and ELM models.The mean relative errors(MRE)of the PLS-ELM model were 1.58%for the training dataset and 1.69%for the testing dataset.The prediction precision of the PLS-ELM model is higher than those of the BP,SVM and ELM models.The consumption time of the PLS-ELM model is also shorter than that of the BP,SVM and ELM models.

Feasibility Analysis on the Integrated Application of Solar Energy, Biogas, Coal-fired Boiler and Radiant Floor Heating for Rural Residence

The feasibility of adopting a balanced energy mix mode (domestic solar energy, biogas, coal-fired boiler and radiant floor heating) was proposed. Taking a typical rural residence in Zhengzhou City for example, the study through theoretical analysis and calculation showed that such a balanced energy mix is an economic way and efficient in saving energy and reducing air pollution, and elaborated the theoretical feasibility of popularizing such a heat supply mode in rural areas.

R&D and Demonstration of Large Domestic CFB Boilers

In order to develop large CFB boilers with independent intellectual property, Xi'an Thermal Power Research Institute (TPRI) established a laboratory with complete functions for the technical development of CFB boilers. This laboratory consists of a 1-MW and a 4-MW CFB combustion test facilities and a laboratory for limestone desulphurization performance evaluation. It carried out tests on CFB combustion and desulphurization for Chinese typical coals and limestone and research on heat-transfer characteristics and key parts, and developed the first home-made 100-MW CFB boiler. Based on the experience of R&D, the laboratory further researched key techniques for enlarging capacity systematically, and cooperating with Harbin Boiler Co. (HBC), developed the first domestic 210-MW CFB boiler with independent intellectual property and put it into engineering demonstration, laying a solid foundation for the development of CFB boilers of even larger capacity.

System Performance and Pollution Emission of Biomass Gas Co-Firing in a Coal-Fired Boiler

To reduce greenhouse gases emission and increase the renewable energy utilization portion in the world, the biomass gasification coupled with a coal-fired boiler power generation system is studied. It is a challenge to achieve optimum performance for the coupled system. The models of biomass gasification coupled with co-firing of coal in a boiler have been established. A comparative study of three kinds of biomass (Food Rubbish, Straw and Wood Pellets) has been done. The syngas produced in a 10 t/h gasifier is fed to a 330 MWe coal-fired boiler for co-combustion, and the co-firing performances have been compared with pure coal combustion case under the conditions of constant boiler load. Results show that co-firing decreases the furnace combustion temperature and raises the flue gas temperature for Food Rubbish and Straw, while, flue gases temperature decrease in case of Wood Pellets. At the same time NOx and SOx emissions have reduced. The system efficiencies at constant load for Food Rubbish, Straw and Wood Pellets are 83.25%, 83.88% and 82.56% when the optimum conditions of gasification and co-firing process are guaranteed.

Comprehensive evaluation for efficient development of coal-fired Industry boiler clearing

The Paper has introduced development of domesticand foreign coal-fired industry boiler and has implementedcomprehensive comparison for several substitution technologies（coal powder boiler, coal water mixture boiler, coal-fired boiler,gas-fired boiler and biomass boiler, etc.） of backward coal-firedindustrial boiler in technology, economy and environment, etc.;has evaluated comprehensive effect and adaptiveconditions of coal-fired industry boiler technology and has put forward suggestion forefficient development of coal-fired industry boiler clearing.

稠油开采注汽锅炉在线综合预警关键技术

为了对工作在高温高压下注汽锅炉的各项运行参数进行在线准确监测和异常预警,本文在对稠油开采注汽锅炉工况参数进行采集、处理、分析的基础上,提出对注汽锅炉显性故障和隐性故障进行检测的方案。采用长期短期记忆神经网络,利用锅炉的时序数据对系统进行分析和建模,完成锅炉显性故障检测和预警,并通过预测数据的方式缓解锅炉大时滞的特性;利用深度异常检测技术,将无故障判别标准的数据进行隐性故障分析和预警。本文提出的综合预警方案对克拉玛依油田注汽锅炉进行了实验验证,预测误差仅有0.08%,同时异常检测范围也在设定值范围内。

工业锅炉安全评价及在线监测方法研究

工业锅炉作为热源或动力源普遍用于生产生活的各个方面,但是工业锅炉运维水平较低,容易发生锅炉爆炸等严重事故。因此,本文结合大型体育赛事举办背景,通过对实际工业锅炉事故的深入分析,总结出工业锅炉四类严重事故及其发生原因,形成基于安保措施和使用场景的工业锅炉安全评价预警方法,根据此方法开发工业锅炉在线监测及预警系统,并成功用于大型体育赛事用工业锅炉,实现对实际工业锅炉的实时监测与预警,保障其安全稳定运行。

大容量W火焰锅炉尿素热解制氨技术研究及应用

随着国家对生产安全的日益重视,液氨作为脱硝还原剂受到越发严格的监管,脱硝还原剂供应由液氨改为尿素制氨是必要的。而大容量W火焰锅炉因基础NOx质量浓度高,需氨量大。因此,提出1种大容量W火焰锅炉尿素热解制氨技术方案,同时针对系统运行期间暴露出的气气换热器旁路调节能力不足、尿素溶液含有杂质等问题,进行相应的设计优化,为采用尿素热解制氨技术的燃煤机组运行提供借鉴。

提高烧结余热发电量的研究与应用

针对影响烧结余热发电量的原因进行系统的分析和研究,主要研究在现有烧结机各种运行工况下,通过对发电机运行的控制难点进行分析、总结,研究内部、外部环境对提高发电量的影响因素及相关主要事项,并制定解决方法及操作规定,达到提高烧结余热发电量,节能降耗目的。

中美标准锅炉大板梁分段设计方法对比

为降低运输成本、满足吊装及运输条件,660 MW及以上锅炉大板梁一般需要在高度方向和长度方向采用分段设计,形成分段式叠梁,高度方向和长度方向的连接均采用高强度螺栓连接。结合贵州某660 MW锅炉具体工程实例,给出了锅炉分段式叠梁运用中国GB 50017—2017《钢结构设计标准》和美国ANSI/AISC 360-16 Specification for Structural Steel Buildings(LRFD方法)的翼缘拼接、腹板拼接、叠合面翼缘拼接的设计方法。对于分段连接所用的高强度螺栓,美国规范计算得到的单颗螺栓承载力较大,螺栓数的需求较少,中国标准偏于安全。对于分段连接处板材,采用美国规范计算的应力系数低于采用中国标准计算的应力系数。对于大板梁分段设计,中美规范的安全水准基本一致,中国规范略偏保守。研究结果为锅炉分段式叠梁的连接设计提供了参考。

安钢3号烧结机烟道余热锅炉系统

以安钢烧结3号烧结机为研究对象,通过在烧结机大烟道安装烟气余热回收装置,有效地利用了烧结机尾部高温烟气的余热,提高了能源的利用率,实现了资源的高效利用,进而降低了烧结工序生产成本,减少了污染物的排放,节能减排效果显著,为其他相关企业提供了借鉴。

Flexibility of a 300 MW Arch Firing Boiler Burning Low Quality Coals

Experimental investigations on the flexibility of a 300 MW Arch Firing (AF) coal-fired boiler when burning low quality coals is reported. Measurements of gas temperature and species concentration and char sampling using a water-cooled suction pyrometer were carried out along the furnace elevation. The carbon content and the size distribu-tions of the char samples were obtained. The char morphology was examined using a field emission scanning electron microscope (FESEM). The char sampling was performed on this type of boiler for the first time. The results indicate that the flexibility of this boiler burning low quality coals under a moderate boiler load is better than its flexibility under a high boiler load. Because of the insufficient capacity of the coal pulverizers used,in case of low coal quality the pul-verized coal fineness will drastically decrease under high boiler loads. This causes an increase in the loss due to incom-plete mechanical and chemical combustion. This is the main cause of a low burnout degree of the pulverized coal and the decrease of the flexibility of this AF boiler under a high boiler load.

Development of 600 MW Class Coal Fired Boilers in China

This article introduces the present status anddevelopment of 600 MW class boilers in China. The statisticaldata indicate that most 600 MW generating units experiencedrelatively length" growing up" period. In this period, unitscould not operate stably , their unplanned outage times weremany and durations long, and availabilities low. On the basis oftesting and research and the summing-up of practice, it wasindicated slagging in the furnace, deviation of tine gas energy atthe exit of furnace, and overheating bursting of superheater andreheater etc, endangering the safety and economics ofoperation,main problems could be completely alleviated oravoided through design and type selection of boiler furnace andburners, coal characteristics and coal handling management,and optimization management of operation conditions etc.