The Application of Polyethersulfone Ultrafiltration Membranes for Separation of Car Wash Wastewaters: Experiments and Modelling

Abstract

The wastewater generated as a result of car washes is considered a new source of water. However, recovered water must meet the required quality criteria for reuse. For this purpose, the ultrafiltration (UF) process can be successfully used. The main aim of the present work was to investigate the influence of the membrane’s molecular weight cut-off (MWCO) on the UF performance in terms of the fouling phenomenon and retention degree of car wash wastewater. Moreover, for a better understanding of the fouling mechanisms, Hermia’s model was used. The experimental studies were conducted with the use of two polyethersulfone (PES) membranes (MWCO of 10 kDa and 100 kDa). It has been noted that the used membranes provided a high-quality permeate and excellent turbidity removal, up to 99%. Moreover, it has been noted that the MWCO membrane has a significant impact on the fouling mechanism. Generally, a much greater intensity of fouling for the membrane with MWCO of 100 kDa was observed. Results obtained in the present study showed that both real wastewaters and the clean solutions used for washing cars cause the fouling phenomenon. It has been proven that rinsing the membranes with water is not sufficient to recover the initial membrane’s performance. Hence, periodic chemical cleaning of the membranes was required. Fitting the experimental data to Hermia’s model allowed us to indicate that membranes with MWCO of 100 kDa are more prone to intermediate blocking. To sum up, the findings suggest that for the UF of the car wash wastewater, the use of membranes with MWCO equal to 10 kDa is recommended.

The Resistance of Polyethersulfone Membranes on the Alkaline Cleaning Solutions

“…Polyethersulfone (PES) is one of the most promising membrane materials used in the ultrafiltration (UF) of water [5][6][7][8][9]. PES has both excellent chemical and thermal resistances over a wide range of pH, from 2 to 12 [1,10,11]. For this reason, PES membranes have also been successfully used to treat wastewater from a car wash, where a cleaning agent with a different pH value was used [11].…”

“…PES has both excellent chemical and thermal resistances over a wide range of pH, from 2 to 12 [1,10,11]. For this reason, PES membranes have also been successfully used to treat wastewater from a car wash, where a cleaning agent with a different pH value was used [11]. However, PES is relatively hydrophobic, which may accelerate the membrane-fouling phenomenon [9,12].…”

Carwash Oily Wastewater Separated by Ultrafiltration

“…However, an analysis of the permeate composition carried out after adding Active Green did not show the presence of oil. The application of the Hermia model showed that during the UF of carwash wastewater, the dominant fouling mechanism was the cake formation [29,34]. A similar result for emulsions stabilized with surfactants was presented in [32].…”

Optimization of isotropic MoS2/PES membranes for efficient treatment of industrial oily wastewater

“…20,21 Membrane technology has also been extended to treating wastewater, such as car-wash wastewater, which is composed of different species of foulants such as grease, detergents, oils, heavy metals and sand. 22 However, the water obtained from the treatment of wastewater containing multiple foulants should meet the required quality standards to be permitted for reuse in other applications.…”