CFB-FGD脱硫塔密相区固体颗粒径向运动特性研究

Radial Motion Characteristics of Solid Particles in CFB-FGD Desulfurization Tower Dense Phase

针对循环流化床烟气脱硫(circulating fluid bed-flue gasdesulfurization,CFB-FGD)过程中遇到的塔内黏壁问题,搭建烟气循环流化床冷态实验台,根据相似理论进行模化试验研究。采用粒子图像测速技术(particle image velocimetry,PIV)对导流板前给料、单侧给料和双侧给料3种不同布置方式下脱硫塔内反应密相区脱硫剂颗粒的径向速度和加速度进行研究,以分析不同给料方式下固体颗粒对脱硫塔壁的冲击和黏附状况。实验结果表明,在双侧给料工况下,固体颗粒的冲壁程度最小,有利于改善塔内黏壁的问题,减少壁面上脱硫灰结垢和给料口积灰,保持脱硫系统稳定运行。

To solve the problem of tower wall sticking in circulating fluidized bed flue gas desulfurization （CFB-FGD） technology, a flue gas circulating fluidized bed cold state test bench was built based on the similarity theory model of experimental research. Through the method of particle image velocimetry （PIV）, the radial velocity and acceleration of desulfurizer particles in the dense phase area of the desulfurizing tower under three kinds of feeding modes were compared. The feeding modes were before deflector feeding, unilateral feeding and bilateral feeding. The condition of impact and adhesion of solid particles to the desulfurization tower was analyzed by PIV. The experimental results show that the extent of the impact to the wall of solid particles in the tower under the bilateral feeding layout mode is minimal, which is beneficial to improve the adhesion in the tower wall, reduce scaling of the ash of desulfuration on the wall and the ash clogging in the feeding entrance, and keep the stable operation of the desulfurization system.