Optimization of coagulation conditions for pretreatment of microfiltration process using response surface methodology

Abstract

The application of coagulation for feed water pretreatment prior to microfiltration (MF) process has been widely adopted to alleviate fouling due to particles and organic matters in feed water. However, the efficiency of coagulation pretreatment for MF is sensitive to its operation conditions such as pH and coagulant dose. Moreover, the optimum coagulation condition for MF process is different from that for rapid sand filtration in conventional drinking water treatment. In this study, the use of response surface methodology (RSM) was attempted to determine coagulation conditions optimized for pretreatment of MF. The center-united experimental design was used to quantify the effects of coagulant dose and pH on the control of fouling control as well as the removal organic matters. A MF membrane (SDI Samsung, Korea) made of polyvinylidene fluoride (PVDF) was used for the filtration experiments. Poly aluminum chloride (PAC) was used as the coagulant and a series of jar tests were conducted under various conditions. The flux was 90 L/m 2 -h and the fouling rate were calculated in each condition. As a result of this study, an empirical model was derived to explore the optimized conditions for coagulant dose and pH for minimization of the fouling rate. This model also allowed the prediction of the efficiency of the coagulation efficiency. The experimental results were in good agreement with the predictions, suggesting that RSM has potential as a practical method for modeling the coagulation pretreatment for MF.

Making Fe0-Based Filters a Universal Solution for Safe Drinking Water Provision

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Assessing desalination pretreatment conditions towards pilot scale‐up using Box‐Behnken experimental design

“…RSM was applied as a statistical and mathematical method which is used mainly to design experiments, reduce the number of planned experiments and assess the relationship between input and output factors (Apostol et al ., 2011; Jung et al ., 2015; Sarrai et al ., 2016; Tassalit et al ., 2016; Watson et al ., 2016; Arhin et al ., 2018; Djerroud et al ., 2018; Dehghani et al ., 2018; Mohammadi et al ., 2018). A Box‐Behnken Design (BBD) with three independent variables was used to investigate the effect of coagulant dose, slow stirring time and slow stirring velocity on the turbidity removal efficiency and residual metal concentration.…”

Influence of microbial floatation on membrane fouling due to particles and organic matters in submerged microfiltration

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