Abstract: To solve the problem of difficult removal of PM_2.5, an orthogonal experiment was designed to effects of charge-characteristics of water mist and dust-laden air velocity on efficiency of PM_2.5 removal were studied by carrying out orthogonal experiments. Experimental data were processed by the analysis method of linear regression. A regression model was built for PM_2.5 removal efficiency. The results show that the regression model is an effective one and can be used to predict the efficiency of PM_2.5 removal, that when the charge voltage(x₁) is 12 kV, electrodes distance(x₂) is 15 mm, electrode ring diameter(x₃) is 60 mm, gas-liquid ratio(x₄) is 1.5, nozzle diameter(x₅) is 0.6 mm, dusty airflow velocity(x₆) is 4 m/s, the optimal value of PM_2.5 removal efficiency is 97.26%, that there is a positive correlation between factors-x₁, x₂, x₄ and PM_2.5 removal efficiency, and a negative correlation between factors-x₃, x₅, x₆ and PM_2.5 removal efficiency, and that the importance ranking of factors is x₁>x₆>x₄>x₅>x₃>x₂.

Key words: charged spray, atomization parameters, orthogonal experiment, regression analysis, PM_2.5 removal efficiency