Novel low-fouling membrane bioreactor (MBR) for industrial wastewater treatment

Abstract

a b s t r a c tA novel antifouling coating of ultrafiltration (UF) commercial membranes, based on a polymerisable bicontinuous microemulsion (PBM) technique, was developed and tested for the first time in a membrane bioreactor (MBR) using an artificial model textile dye wastewater and compared with a commercial uncoated UF membrane. The results showed that the commercial MBR module faced severe fouling problems whereas the novel coated PBM MBR module reduced the fouling significantly. The analysis of fouling rate using a resistance model confirms that PBM coated membrane has a higher antifouling effect. The antimicrobial properties of the PBM membrane contributed by polymerisable cationic surfactant acryloyloxyundecyltriethylammonium bromide (AUTEAB) guaranteed an anti-biofouling effect preventing the growth of microorganisms on the membrane surface. In addition, the PBM MBR module showed 10 71% higher blue dye removal efficiency and a similar rate of COD removal efficiency of about 957 1% compared to commercial module. However, water permeability was slightly lower due to extra resistance of the PBM coating. Root mean squared (RMS) roughness measurement and analysis of AFM images confirmed that the stable novel membrane coating still existed and showed antimicrobial effect even after 105 days of operation. The results obtained demonstrated the potential of the low fouling PBM membrane.

Novel low-fouling membranes from lab to pilot application in textile wastewater treatment

“…11), it is evident that the coated membrane is less prone to fouling which ensures the much longer life time and making the PBM coating a very promising approach. The result of the present work has been compared with other two studies in which the PBM membrane concept has been developed for water treatment [15,25]. The PBM membranes produced typically differ for the use of a specific surfactant: lab-made and polymerisable surfactant AUTEAB in case of the previous studies; and commercial not-polymerisable [34] DTAB surfactant in case of the present work.…”

“…[14] [15] (WTW GmbH, Germany). Conductivity measurements were conducted with a conductivity meter (Model: Cond 315i meter; WTW).…”

“…To deal with the problems associated with textile effluents, several studies have been directed at the treatment of polluted streams close to the point of source, as in the integrated approach [8][9][10] and at the treatment of the final effluents (end of pipe approach) [11][12][13][14]. MBR technology, which combines the benefits of high biomass concentrations with the possibility to run a continuous process at controlled biomass retention [2], is recognised as a promising technology to provide water with reliable quality for re-use, and it is very attractive for industrial wastewater treatment [15][16][17]. Since the membrane costs have decreased dramatically over the last years to currently approximately 50 Euro/m 2 [18] and energy requirements for aeration of the membrane are also fast approaching the normal activated sludge process (ASP) range, this has now become an economically feasible solution for wastewater treatment.…”

“…Colloidal and soluble foulants (SMP) can cause pore blocking and irreversible fouling due to their small size. To mitigate fouling problems, many researchers have followed different techniques [15].…”

“…Composition of the model textile dye wastewater (MTDW)(15) Industrial textile wastewaterThe study was conducted with real RTW samples supplied from the Tunisian textile factory SITEX located in Kasr Hellal, Tunisia. The company production line comprises dying fabrics and finishing processes and utilizes different dyes (reactive, direct and sulphur) and chemical substances such as detergents, salts, auxiliaries (e.g.…”