团聚室中引入气固射流,使团聚室内形成局部湍流,强化颗粒间的碰撞.以撞击式采样器测量燃煤飞灰可吸入颗粒团聚前后质量变化来反映颗粒的团聚情况.实验结果表明,引入气固射流后,颗粒在团聚室内团聚沉降,撞击式采样器收集到的颗粒质量减少,颗粒清除效率提高.加入粗颗粒可有效提高可吸入颗粒清除效率,且随粗颗粒粒径增大,清除效率提高更加明显.增大射流气体流速,颗粒清除效率明显提高.当射流垂直于主气流进入团聚室时,可吸入颗粒清除效率最高,射流逆向倾斜入射时颗粒清除效率高于射流同向入射清除效率.%In order to intensify the collision among the inhalable particles, a gas-solid jet flow was introduced into the agglomeration chamber to generate a local turbulent flow field. An aerosol cascade impactor was used to measure the mass change of the fly ash inhalable particles before and after agglomeration. The experimental results show that, because of the action of introduced jet flow, many fly ash inhalable particles agglomerate and settle out in the chamber, which causes that the mass of particles collected in the aerosol cascade decreases and correspondingly the particle removal efficiency increases. The experiments also show that, adding solid particles in the introduced jet flow can raise the removal efficiency; in particular, the addition of coarse solid particles leads to a higher removal efficiency of inhalable particles than that of adding fine particles. It was found that the removal efficiency can be increased significantly by raising the jet flow velocity, and the introduced direction of the jet flow affects the removal efficiency obviously. When the jet flow is introduced in the agglomeration chamber with an angle θ (angle between vectors of jet flow and main gas flow in the chamber)in the range of 90°＜θ＜180° (the jet flow inclines towards the inlet of the main gas flow), the removal efficiency of inhalable particles is higher than that when θ is in the range of 0°＜ θ＜90° (the jet flow inclines towards the outlet of the main gas flow); and there exists a maximum removal efficiency of inhalable particles when the jet flow is introduced perpendicularly (θ= 90°)
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