通过分析沁北电厂三期工程1 000 MW机组无旁路脱硫系统，论证了湿法脱硫系统采用预洗涤系统的必要性。阐述了预洗涤系统的流程、设计原则、设备选型及实际应用。实践证明，烟气预洗涤系统在控制油污、粉尘和防止高温烟气进入脱硫系统方面效果良好。

Through the analysis on no-bypass desulphurization system of 1 000 MW units in Qinbei Power Plant phase Ⅲ project, the necessity of pre-washing treatment system for wet flue gas desulfurization system is deomonstrated, as well as the process, design principles, equipment selection and the practical application of pre-washing treatment system are introduced in this paper. It has been proved that the pre-washing treatment system exerts good effect in oil pollution and dust control, as well as preventing high-temperature flue gas entering the desulfurization system.