错流微滤过程中的反冲规律研究

摘要

采用水-氧化铝颗粒组成的混合物,模拟石油化工领域中常见的液-固分离体系,重点研究该体系错流微滤过程中的反冲规律.以滤膜渗透通量、操作周期内平均滤膜渗透通量和反冲后滤液中颗粒浓度作为评价反冲效果的重要参数,系统考察了反冲时间和反冲压差对反冲效果的影响.结果表明:采用液相反冲技术可以有效降低过滤阻力,恢复滤膜渗透通量,在固含率分别为1%和5%的条件下,反冲过程均在瞬间内完成,反冲时间为1~2 s;反冲压差越高,反冲效果越好,优选的反冲压差为0.5~0.6 MPa.%The slurry containing water and alumina fine particles was used to simulate conventional liquid-solid separation system in petrochemical industry.The backflushing performance in the process of cross-flow microfiltration was studied emphatically.The permeate flux,average permeate flux of the whole duration and the particle concentration in filtrate were used to evaluate the influence of backflushing time and backflushing pressure difference.The experimental results showed that the liquid backflushing technology could reduce filtration resistance and recover permeate flux.In the cases of the suspension system with solid holdup 1% and 5%,respectively,the backflushing operation was finished instantly within 1-2 s.The larger the backflushing pressure difference,the better the backflushing performance.The optimal backflushing pressure difference is 0.5-0.6 MPa.