Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,Southeast University
ChangrongAcoustic Limited Liability Company
State Key Laboratory of Clean and Efficient Coal-firedPower Generation and Pollution Control

目前国内火电燃煤机组广泛采用的石灰石−石膏湿法脱硫系统会产生大量颗粒物,传统除尘除雾装置对粒径较小的颗粒物尤其是PM10的脱除效果比较有限。声波团聚对于控制细小颗粒物尤其是PM10的排放具有重要意义,可作为烟尘预处理环节与传统除尘除雾器组合使用。为解决火电机组湿法脱硫后烟气中粉尘特别是PM10的逃逸问题,对烟道进行工程改造试验,配置3200、1600和800Hz频率的不同组合方案,探究其对PM10数量浓度、粒径分布的影响,选取其中团聚效果最好的声波组合方案,分别测试背景工况、声波单独作用、声波耦合喷雾作用时的除尘效率。结果表明:未开启声波时PM10数量浓度较高,为2.75×104cm−3,峰值粒径在0.05μm左右,声波开启后PM10的数量浓度明显降低,且峰值粒径增大,多种组合方案中3200Hz×4+1600Hz×2的声波组合方案PM10的数量浓度最低,为2.26×104cm−3,代表此方案团聚效率最高,为17.82%。除尘效率的测试中,除雾器单独作用时除尘效率较低,仅为34.3%,配合上述声波可将除尘效率提升至52.1%,再辅助喷雾时除尘效率最高,达到60.4%,此时除雾器出口烟尘质量浓度降至5mg/m3以下,满足超低排放要求。此外,对于试验中的低质量浓度PM10环境,声波团聚规律依然适用,但颗粒物碰撞概率较低,可采用高低频声波组合的方案弥补。

At present,the limestone-gypsum wet desulfurization system is widely used in domestic thermal coal-fired power units,whichgenerates a large amount of particulate matter,and the traditional dust and mist elimination devices have a relatively limited effect on theremoval of particulate matter with small particle size,especially PM10. Acoustic agglomeration is important for controlling the emission offine particulate matter,especially PM10,and can be used as a pretreatment link for soot in combination with conventional dust and misteliminators. To solve the problem of fugitive dust, especially PM10, in the flue gas of thermal power units after wet desulfurization,engineering modification tests are conducted on the flue,configured with different combinations of 3200,1600 and 800 Hz frequencies toinvestigate their effects on PM10 quantity concentration and particle size distribution,and the combination of acoustic waves with the bestagglomeration effect was selected. The dust removal efficiency is tested under background conditions,acoustic wave alone,and acoustic wave coupled with spray. The results show that the number concentration of PM10 is higher when the acoustic wave is not turned on, which is 2.75×10 cm,and the peak particle size is about 0.05 μm. The number concentration of PM10 decreases significantly after the acoustic wave is turned on,the peak particle size increases,and the number concentration of PM10 is the lowest in the combination of 3200 Hz×4+1600 Hz×2,which is 2.26×10 cm. This number represents the highest agglomeration efficiency of 17.82%. In the test of dust removal efficiency,the dust removal efficiency is low when the mist eliminator acts alone,only 34.3%,with the above-mentioned acoustic waves,the dust removal efficiency increases to 52.1%,and then the highest dust removal efficiency is achieved when the auxiliary spray is used,reaching 60.4%,at which time the dust concentration at the outlet of the mist eliminator drops to below 5 mg/m,meeting the ultra-low emission requirements. In addition,for the low concentration PM10 environment in the test,the acoustic wave agglomeration law is still applicable,but the particle collision probability is low,which can be compensated by a combination of high and low frequency acoustic wave.

江苏省科技成果转化专项资助项目(BA2020001)

魏泽坤,黄亚继,刘宇清,等.声波团聚净化火电300MW机组湿法脱硫后烟气试验[J].洁净煤技术,2024,30(11):51−58.

WEI Zekun,HUANG Yaji,LIU Yuqing,et al. Experimental study of purifying flue gas after wet desulfurization in thermal power 300 MW units by acoustic agglomeration[J].Clean Coal Technology,2024,30(11):51−58.