• Journal of Korean Society of Water and Wastewater
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• v.20 no.2
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• pp.235-244
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• 2006

A PCF(Pore Controllable Fiber Filter) process was applied as a pretreatment of water treatment for reduction of turbidity. The experimental results obtained from the PCF showed that the removal efficiency of turbidity without coagulation was around over 70 percent. However, the removal efficiency of turbidity by the coagulation-PCF process was high as much as over 95%. Thus, the coagulation pretreatment was required for the better operation of the PCF. The SEM (Scanning Electron Microscope) images of fiber before and after filtration showed that the filtration mechanism of PCF filter is both controlling attachment mechanism and Sieving mechanism through fiber pore. For the coagulation-PCF process, optimum dosage of coagulant was needed for the economical operation, and for this, determining the optimum dosage by using a filter column test. Also only 16mg/L of alum was used to obtain high algae removal efficiency over 90%. Therefore, it can be concluded that coagulation-PCF process is very effective pretreatment process for algae removal.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.2
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• pp.135-143
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• 2005

It was evaluated that the effect of turbidity removal by Pore Controllable Fiber Filter(PCF) installed in NS(Naksang) small water treatmant plant(system) using under flow water as raw water in the study. The results of the study are as the followings. Firstly, the removal efficiency of turbidity by PCF without coagulation(in operation mode not using coagulants) was mostly below 20 percent. On the other hand, when operation using proper coagulants, that of turbidity was mostly over 80 percent. Secondly, slow sand filtration after PCF, total turbidity removal efficiency of final treated water was 84.3 percent, and the contribution by PCF was 57.1 percent and that of slow sand filtration was 27.7 percent. Therefore the introduction of PCF as pre-treatment process would be helpful to reduce the loading of high turbidity of slow sand filtration. Thirdly, the results of particle counter measurements showed that when operated PCF with coagulants, fine flocs captured or adsorbed at the pore of PCF were flow out into the effluents from 120 minutes after backwashing because of the increase of headloss of PCF. Therefore the decision of backwashing time should made consideration into the outflow of fine flocs from PCF. Fourth, coagulant dosages on PCF at the same turbidity was largely variable because of the effect of the raw water characteristics and the turbidity increase velocity at rainy days, therefore flexible coagulant dosages should be considered rather than fixed coagulant dosage by the influent jar-test result.