摘要
我国电力行业循环流化床(circulating fluidized bed,CFB)锅炉技术趋于成熟,标准化程度较高;410 t/h以下容量在非电力行业占比较大,新技术应用相对滞后,节能减排仍有较大潜力。结合某化工企业130 t/h CFB锅炉节能需求,主要依据电力行业CFB锅炉标准,研究了锅炉低负荷稳燃试验方案。通过布风板阻力、临界流化和点火等基础性试验,确定了低负荷稳燃关键参数限值;进一步开展的低负荷试验,将锅炉最低稳燃负荷由55 t/h降至45 t/h,由此杜绝了锅炉运行中因对空排汽造成的能量浪费,显著提高了运行经济性。试验结果一方面说明了CFB锅炉试验方案及关键参数的研究与确认对于试验目标实现的重要性;另一方面也说明,对于应用场景类似,新技术跨行业快速传播能够促进我国节能和碳减排等领域目标的实现。同时,实炉测试了N_(2)O的排放特性,结果表明,锅炉负荷由120 t/h降至45 t/h,N_(2)O排放质量浓度由29.5 mg/m^(3)升至361.4 mg/m^(3),低负荷工况N_(2)O排放质量浓度的大幅度提高将成为CFB锅炉污染物控制面临的新挑战。结合试验研究结果,提出了CFB锅炉燃用贫煤N_(2)O和NO_(x)协同控制初步技术路线。运行技术方面,采用空气分级控制密相区燃烧气氛、低氧燃烧、适当提高床温等方法,有利于两种污染物排放总量控制;设备技术方面,采用外置床换热器等调温装置控制锅炉不同负荷燃烧温度,布风装置结构优化降低锅炉低负荷运行氧量(体积分数),有望达到较高的协同控制效果。
The development of circulating fluidized bed(CFB)boiler technology in China’s thermal power in⁃dustry tends to be mature and the degree of standardization is high.The capacity below 410 t/h accounts for a large proportion in the non-power industry,and the application of new technologies is relatively lagging behind,so there is still great potential for energy conservation and emission reduction.Based on the energy-saving re⁃quirements of a 130 t/h CFB boiler in a certain chemical enterprise,the low-load stable combustion test scheme of the boiler was studied mainly according to the CFB boiler standard of the power industry.Through the basic tests of air distributor resistance,critical fluidization and ignition,the key parameter limits for low-load stable combustion were determined.Further low-load tests were carried out to reduce the minimum stable combustion load of the boiler from 55 t/h to 45 t/h,thereby eliminating the energy waste caused by steam exhaust during boil⁃er operation and significantly improving the operation economy.On the one hand,the test results show the impor⁃tance of the research and confirmation of CFB boiler test scheme and key parameters for the realization of test ob⁃jectives.On the other hand,these also show that for similar application scenarios,the rapid spread of new tech⁃nologies across industries can promote the realization of China’s energy-saving and carbon emission reduction goals.The N_(2)O emission characteristics were also tested in the actual furnace.The results show that the boiler load is reduced from 120 t/h to 45 t/h,and the N_(2)O emission mass concentration is increased from 29.5 mg/m^(3)to 361.4 mg/m^(3).The substantial increase of N_(2)O emission mass concentration under low-load conditions will become a new challenge for CFB boiler pollutant control.Combined with the experimental results,the prelimi⁃nary technical route of coordinated control of N_(2)O and NO_(x)in CFB boiler burning lean coal is proposed.In terms of operational technology,adopting methods such as air classification to control the combustion atmosphere in the dense phase zone,low oxygen combustion,and appropriately increasing the bed temperature is beneficial for controlling the total emissions of the two pollutants.In terms of equipment technology,temperature regulat⁃ing devices such as external bed heat exchangers are used to control the combustion temperature of the boiler at different loads,and the structure of the air distribution device is optimized to reduce the oxygen body integral value during low load operation of the boiler,which are expected to achieve a high collaborative control effect.
作者
金森旺
陈久全
符志国
孙雨薇
JIN Senwang;CHEN Jiuquan;FU Zhiguo;SUN Yuwei(School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Sichuan Lu Tian Hua Share Co.,Ltd.,Luzhou 646300,China;Xi’an Thermal Power Research Institute Co.,Ltd.,Xi’an 710054,China)
出处
《电力学报》
2023年第6期478-487,共10页
Journal of Electric Power
作者简介
金森旺(1979-),男,博士研究生,正高级工程师,主要研究方向为循环流化床锅炉及污染物控制技术,氢能制储技术,2540428097@qq.com;陈久全(1983-),男,高级工程师,主要从事CFB锅炉运行管理、新技术开发与工程应用;符志国(1985-),男,工程师,主要从事CFB锅炉运行管理、新技术开发与工程应用;孙雨薇(1990-),女,硕士,会计师,主要研究方向为财务管理研究。
