V型滤池中气水反冲洗条件下滤层配置特征的变化

Revolution of filter media configurations with water and air scour backwashing in V-Filter

均质滤料和气水反冲洗技术的应用是V型滤池高效运行的核心,监测表明不同使用龄期的滤层内有效粒径d10和不均匀系数K80基本稳定,但滤池中滤料配置特征,包括等体积直径dv和球形度系数ψ,随滤层深度呈现出特定的分布特征.采用滤层截污量分布、反冲洗后滤料表面残余含泥量分布以及截留污泥剥离性能测定,对滤层配置特征的变化进行了对比分析.结果显示,生产滤池中反冲洗效果最差的部位位于滤层内部,滤料比表面积的分布对截污量分布的影响不大,但与反冲洗完毕滤料表面残留污泥的分布规律一致.论文结论有助于气水反冲洗技术的理论发展,并为生产滤池提高反冲洗运行效率提供依据.

The application of uniform media configuration and air scour assisted backwash system are essential to long term successful service in V-Filter.The survey results in several plants revealed that the effective size(ES) d10 and uniformity coefficient(UC) K80 can keep stable with deferent aged period.However,the configuration characteristics,such as grain diameter of sphere of equal volume(dv) and sphericity(ψ),will shift from uniform with depth in filter.This revolution was explained and analyzed with the distribution of deposit,survival deposit after backwash and the detachment performance of deposit in situ filter.The analysis revealed that the worst backwash efficiency was located 20~30 cm below the surface of media in filter,and the distribution with depth of the specific surface of grains resemble the survival deposit after backwash and no relation with deposit in media porous.The conclusions drawn here will benefit the mechanism research on air scour and water backwash,and promote the innovation of filter backwash techniques.