化学团聚促进电除尘脱除烟气中PM2.5和SO3

化学团聚技术是实现燃煤烟气超净排放的有效技术之一，采用燃煤热态实验系统，分析探讨化学团聚技术促进电除尘对PM_2.5和SO₃的脱除作用，考察了化学团聚剂添加前后细颗粒化学组分及粒径的变化，以及化学团聚室、电除尘出口PM_2.5和SO₃浓度变化，并分析促进PM_2.5和SO₃脱除的机理。结果表明：喷入化学团聚剂后，细颗粒粒径峰值由0.1 μm增大到3 μm左右，细颗粒化学组分基本保持不变；电除尘出口细颗粒物数量浓度由5.8×104 cm^-3降低到3.2×104 cm^-3，电除尘效率提高45%；烟气SO₃浓度由40 mg·m^-3提高到100 mg·m^-3时，单一化学团聚对SO₃的脱除效率由42%提高到68%，协同电除尘SO₃脱除效率由66%提高到86%。

Simultaneous control of PM2.5 and SO3 by chemical agglomeration collaborative electrostatic precipitation

Chemical agglomeration is one of the effective technology to realize ultar-low emission for coal-fired power plants. The removal of PM_2.5 and SO₃ from coal combustion by chemical agglomeration was investigated experimentally based on the coal-fired thermal system. The chemical composition of fine particles, the changes of particle size and the concentration of PM_2.5 and SO₃ were investigated at the chemical reunion chamber and electric outlet. The mechanism of removing PM_2.5 and SO₃ was analyzed. The results showed that the chemical agglomeration evaporation can increase the average size of particles from 0.1 μm to 3 μm, while the particle compositions were mainly uncharged. The fine particle number concentration was reduced from 5.8×104 cm^-3 to 3.2×104 cm^-3 and the electric efficiency was increased by 45% at the electric outlet. When SO₃ concentration in flue gas increased from 40 mg·m^-3 to 100 mg·m^-3, the removal efficiency of SO₃ of a single chemical agglomeration increased from 42% to 68%, coordinated the electric SO₃ removal efficiency by 66% to 86%. The chemical agglomeration collaborative electrostatic precipitation can be efficient for the removal of PM_2.5 and SO₃.