采用中径3.3μm的细颗粒在PPS普通滤料和涤纶覆膜滤料表面形成不同沉积量的颗粒层,用缓慢增加反吹气流和低压脉冲清灰的方法进行清灰测试.随着颗粒层沉积量增加,颗粒层低压脉冲清灰的效率均提高,缓慢反吹的清灰力也呈减小趋势.涤纶覆膜滤料表面颗粒层沉积量从200g/m^2增长到401g/m^2时,平均清灰应力从350N/m^2降到100N/m^2,比PPS滤料低90N/m^2以上.PPS滤料上低压脉冲清灰效率随颗粒层沉积量的增加线性增加,涤纶覆膜滤料上颗粒层沉积量超过200g/m^2时非线性快速增加,缓慢反吹产生的颗粒层碎片均随着颗粒层沉积量增加而增大.
Fine particles with mean size of 3.31 μm were used to form cakes on PPS filter or PET membrane filter with different deposit loadings. With a slowly increased reverse flow, the cakes were slowly blown out and the cake cleaning stress curve was measured. Meanwhile a low pressure pulse cleaning method was used to simulate the real pulse cleaning in practice. The results by both methods were compared and exhibited the agreement in predicting cleaning stress. The cake detachment stress decreased as the cake loading increases for both filters. For instance, the detachment stress of PET membrane filter decreased from 350 to 100 N/m^2 as the cake loading increased from 200 to 401 g/m^2, which was 90 N/m^2 lower than that of the PPS filter. The low pressure pulse cleaning efficiency of PPS filter cakes showed a linear relationship to the cake loading, while the efficiency of PET membrane filter increased much quickly when the cake loading was lower than 200 g/m^2. The cake patches obviously became larger as the cake loading increases for both filters.