Suitability of Modified PES Membranes for Closed Water System in Rubber Industry

The purpose of the study was to evaluate the suitability of modified polyethersulfone (PES) ultrafiltration membranes for application in a closed water circulation system within a rubber industry facility. Research focused on analyzing the transport and separation properties of tubular membranes during ultrafiltration of wastewater generated from the washing vulcanized rubber hoses. The experiments were carried out using the UF-1 membrane system supplied by APEKO SP. z o.o. The study assessed the efficiency of ultrafiltration membranes in wastewater purification and their regeneration effectiveness. Key parameters to evaluate ultrafiltration performance included separation coefficients (R, %) for non-ionic surfactants (NS) and chemical oxygen demand (COD). The results demonstrated that the tested membranes significantly improved the visual quality of the wastewater and exhibited a high separation efficiency for the analyzed contaminants (RNS =95%, RCOD =85%). However, during closed-loop filtration at 20× contaminant concentration in the retentate, membrane fouling substantially reduced its hydraulic performance. Chemical cleaning after three consecutive filtration cycles restored approximately 70% of the initial efficiency of the membranes. These findings highlight the potential of modified PES membranes for industrial wastewater treatment while highlighting the need for optimized fouling mitigation strategies in closed-loop applications.