Membrane Fouling Mitigation in Water Filtration Using Piezoelectrics

The clogging of filtration membrane by particles otherwise known as fouling is a major concern in membrane filtration technology due reduction of flux, membrane lifespan and system performance, with an associated increase in process and operating costs in industries that utilize membrane in their production process. Cleaning or replacement of a fouled membrane requires production to be interrupted or the entire system to be shut down. This is because the cleaning or replacement of the fouled membrane requires production to be interrupted for the cleaning process or the entire system to be shut down for the replacement process to take place, leading to great losses to the industries involved. Many approaches have been devised over the years to tackle this problem, of which not only undermine the performance of the filtration membrane but also contribute to great losses to industries that apply them. Cheaper and more efficient means of fouling control remains the key to solving this problem.

A water filtration system is proposed that uses piezoelectric crystals attached on a tubular polyvinylidene fluoride (PVDF) membrane to increase flux and delay the clogging of the pores of the filtration membrane (by particles). Filtration tests with mud solution showed that the membrane vibrated with piezoelectrics reduced the clogging of the pores and increased permeate flux of the filtration process as compared to the non-vibrated membrane. To optimize the permeate flux production of the system and fouling reduction, the effects of voltage, concentration and location of piezoelectric crystals were investigated. An equation to best fit the experimental data was developed which can help in the optimization of the variables.