煤粉锅炉燃烧调整对氮氧化物排放量及热效率影响的试验研究

以提高锅炉热效率和降低NO_x排放量为主要目的,对某电厂300 MW机组,HG-1025/17. 5-HM四角切圆锅炉进行了燃烧调整试验研究。试验结果综合反映了锅炉的各个运行工况对氮氧化物排放浓度以及锅炉热效率的影响。通过对各个工况试验结果的分析比较,给出了可以兼顾NO_x排放量和锅炉热效率的运行调整方式。     

锅炉燃烧调整对NOx排放和锅炉效率影响的试验研究

在2台典型的1025 t/h锅炉上进行了燃烧调整降低NOx排放浓度的试验研究,通过改变过量空气系数、辅助风配风方式、运行负荷和制粉系统运行方式等,测定了锅炉尾部烟道NOx排放浓度,分析了锅炉运行工况、运行方式对NOx排放的影响.结果表明:降低过量空气系数,烟煤锅炉NOx减排效果比贫煤锅炉好得多;降低负荷,烟煤锅炉的NOx排放量降低值较大;缩腰式配风的NOx排放浓度比均匀配风方式约降低10%,制粉系统的运行方式影响炉内燃料的燃烧状态和温度分布,也影响NOx的生成和排放.在不降低锅炉效率的前提下,调整燃烧工况,可降低锅炉排放NOx浓度1O%～20%.     

锅炉燃烧的影响因素及其调整

阐述了锅炉燃烧调整的任务和目的,分析了影响燃烧的因素和强化燃烧的措施以及不同煤种的燃烧调整原则,针对锅炉的燃烧调整进行了深入的探讨和研究,为提高锅炉安全、经济运行提供参考和借鉴。     

双层炉排燃烧铸铁锅炉

先后六百余台改造后的双层炉排燃烧铸铁锅炉投入运行以来,历经八年的实践证明,其燃烧热效率可达70％,烟尘含量(不用除尘器)低于120毫克/米~3(标准状况),耐腐蚀、运行、管理、维护简便,是一种较好的热源设备。本文对该炉的运行、特点及其存在问题进行了较详细的叙述。     

流化煤燃烧中氮氧化物的生成机理

在一个流化床反应器和一个固定床反应器中研究了流化床煤燃烧中Ｎ２Ｏ及ＮＯｘ生成的机理。发现流化床煤燃烧中Ｎ２Ｏ和ＮＯｘ主要来自于煤中的氮，即挥发分氮和焦炭氮，部分ＮＯｘ来自于空气中的Ｎ２。     

锅炉燃烧系统优化调整试验研究

分3个不同负荷采用正交试验设计法设置调整工况,并安排了调整工况试验前后的习惯运行方式试验及优化工况试验。结锅炉测试效率进行了环境温度、给水温度及煤种修正,得到锅炉毛效率。全面考虑了锅炉辅机电耗和锅炉主、再热蒸汽温度对机组经济性的影响,提出了锅炉综合效率这一概念。通过试验,提高锅炉运行的经济性和安全性,降低了锅炉NOx排放量,锅炉综合效率平均提高2.29%,炉内燃烧区护膛温度平均提高28℃,NOx排放量平均降低213mg/m^3,为锅炉安全经济运行提供参考。     

生物质电厂锅炉燃烧调整试验研究

分析了生物质发电现状,针对某生物质电厂秸秆锅炉,进行了燃烧调整试验研究,考察了一次风、二次风、燃料性质和锅炉漏风对燃烧的影响.结果表明,加强燃烧中心区通风,协调一、二次风量,可降低锅炉不完全燃烧损失和排烟损失,提高锅炉效率;控制人厂燃料含土量与水分,减少杂物,可提高燃烧安全性;降低锅炉漏风量、调整锅炉配风、可保证锅炉正常运行.为生物质锅炉设计、改造和运行提供了参考.     

基于效率与NOx排放的锅炉燃烧优化试验及分析

电站燃煤锅炉NOx排放的特性非常复杂.电站锅炉的运行需同时考虑降低运行成本和NOx排放,针对国电谏壁电厂300 MW锅炉进行效率与NOx排放试验,找到了适合该锅炉的高效低NOx排放优化运行工况,与习惯运行工况相比,锅炉效率提高了0.64%,NOx排放降低了144 mg/Nm3.     

高炉煤气锅炉燃烧中氮氧化物污染物的控制

文章介绍了氮氧化物生成机理及高炉煤气锅炉燃烧中氮氧化物污染物的控制.通过对NOx生成机理的讨论,高炉煤气燃烧时主要产生的NOX为热力型NOX,采用多层燃烧器的布置,把燃烧器组设计成浓淡燃烧器, 从而降低NOX的生成,使锅炉NOX排放达标,使之成为一种环保型污染气体治理设备.     

Control of nitrogen oxide emissions from coal combustion

The paper gives a discussion of the regulatory framework currently being used to limit nitrogen oxide (NO_x) emissions, with emphasis being placed on EC and UN measures. It then follows with a discussion of the procedures being adopted at present to control or limit these emissions. The topics discussed include combustion modification measures, new combustion technologies, flue gas treatment, selective catalytic reduction, selective noncatalytic reduction and combined SO_x/NO_x processes.     

410 t/h煤粉锅炉燃烧优化调整与分析

针对齐鲁石化热电厂#4炉燃烧状况不佳,灰渣可燃物含量偏高等问题,进行了燃烧优化调整试验。并对试验结果进行了分析,提出了煤粉细度和风量等参数的优化控制值。经过燃烧调整,灰渣可燃物含量有了较大幅度降低。     

300MW对冲燃烧锅炉NOx排放特性及经济性试验研究

针对某电厂一台300 MW前后墙对冲燃烧锅炉,通过上层停运磨通入一次风,改变磨煤机组合、机组负荷、炉膛氧量以及一次风温、一次风量等参数,研究了不同燃烧方式对NOx排放及锅炉经济性的影响,提出了锅炉高效低污染运行的合理方式。     

优化燃烧降低锅炉NO_X排放的试验分析

采用燃烧优化技术进行了降低某厂300MW机组1号锅炉NOx排放的试验,在提高锅炉运行经济性的同时,大大降低了锅炉NOx的排放浓度。分析了该炉热效率和NOx排放浓度与锅炉运行参数的关系,确定了锅炉低NOx运行方式,可用于指导锅炉的高效低NOx的运行。     

锅炉的优化调整与性能试验

对锅炉优化调整的意义、要求、内容和基本方法进行了阐述,指出了锅炉性能试验与优化调整的关系,并以一台410t/h锅炉的燃烧优化调整为例说明了优化调整的具体过程,及其对提高锅炉机组运行经济性、实现节能降耗的必要性。     

The assessment of the fuel additive impact on moving grate boiler efficiency

The purpose of the work is to determine the impact of a commercial coal additive on the efficiency and the pollutants emissions of an industrial boiler. The tests were carried out in a 41.1 MW thermal output moving grate boiler in common operating conditions for a period of two months. At that time, coal was alternately dosed with and without the additive. The amount of the additive to coal ratio was fixed at 1L/Mg during the tests. The additive applied was a 20% aqueous solution of four compounds, i.e. isopropanol, manganese (II) acetate tetrahydrate, acetic acid glacial … % and N,N-Dimethylethanolamine.The samples of coal, bottom and fly ash were collected from the installation twice a day during the tests in order to check their properties. The boiler's main energy parameters and the emission levels of CO, NO_x, SO₂ and dust were measured and registered. The additive influence on the boiler operation was evaluated based on the efficiency and three indicators which highlighted this impact.The additive influence was mainly demonstrated in boiler efficiency increase, in the range of 0.5–1 p.p., as well as the oxygen concentration in the flue gas which indicates that there was a decreased amount of the combustion air. On the other hand, the studies do not show any evident influence on the NO_x, SO₂ and CO emissions with the applied catalyst to fuel ratio. The research showed that even a little improvement of efficiency gives a measurable economic effect.     

Efficiency and emissions of gas-fired industrial boiler fueled with hydrogen-enriched nature gas: A case study of 108 t/h steam boiler

Hydrogen-enriched natural gas (HENG) is a promising low-carbon fuel in the industry. The fuel flexibility of the existing natural gas-fueled industrial combustion equipment is a crucial issue for the HENG application. This study evaluates the thermal and emission performances of a large-scale industrial steam boiler fueled with HENG. Considering different operation strategies, three boiler operation scenarios were proposed, namely, the unchanged fuel/air valve opening (Scenario 1), the maintained boiler capacity with unchanged valve control logic (Scenario 2), and the maintained boiler capacity with unchanged excess air ratio (Scenario 3). A model considering the thermal equilibrium and heat transfer inside the boiler was built to study the thermal efficiency under the three scenarios, and a chemical reaction network model was established to investigate the NOx emission characteristics. The results showed that thermal efficiency and NOx emission presented a similar variation trend. Both of them decreased in Scenarios 1 and 2 while increased in Scenario 3 as hydrogen volumetric fraction in HENG increased from 0 to 0.9. The differences in decarbonization potentials among the three scenarios were limited. This study implies that the trade-off between thermal efficiency and NOx emission should be carefully concerned when applying HENG to industrial steam boilers.     

Research of boiler combustion regulation for reducing NOx emission and its effect on boiler efficiency

The effect of boiler combustion regulation on NO_x emission of two 1025t/h boilers has been studied.The re-searches show that NOx emission is influenced by coal species,operation conditions,etc,and can be reduced byregulating the combustion conditions.The effect of combustion regulation on boiler efficiency has also beenchecked.