The Simulation And Analysis Of Rate Changeson Filtration

Filtration is one of the important unit processes used in the production of potable water. Changes of rate directly affect the filtration cycle and water quality. Study of rate changes has very important significance in water quality control.Rate change frequently in V-filter filtration. The topic is study of impact of rate changes on the filtration by filtering models.Research on difference of effluent quality between several rate surges and 8m/h constant filtration rate by comparing the experiments,research on their difference of solid distribution in filter layer,research on their difference of resistance for deterioration of the flow. Observing and analyzing the affection of rate sudden increase at the end constant-rate filtration run,and compare with effluent quality of rate surges filtration.Test of kaolin flocculation filter shows that:(1) Filter effluent turbidity surged if filter rate surged.Fluctuation range of filter effluent turbidity had relations with the amplitude and frequency of rate surges on Filtration, the greater the amplitude and the higher the frequency rate surges led to the sharper of the filter effluent turbidity.But the average effluent turbidity of the wave filter did not have much different with the constant-rate filter.(2) Filter rate surges increased floe penetration,so that the entire filter layer can be more fully utilized.the greater the amplitude and the higher the frequency rate surges led to greater influence.(3) In the past of constant filter, rate increase reased that turbidity in the effluent rise sharply and then rapidly decline. The period of the maximum is not affected by increase rate.the maximum turbidity of effluent on rate surges filtration is far smaller than maximum at the sudden increase rate on constant speed filter.Test of chemical oxidation-filtration to remove manganese shows that:In the past of constant filter,such as the filter layer is still very protective layer, filter the water rate increase may not appear on the deteriorating situation, but eventually it will breakthrough the filter media in advance.Filter rate surges led to breakthrough early, and breakthrough had a significant phenomenon.