Rejuvenated end-of-life reverse osmosis membranes for landfill leachate treatment and reuse water reclamation

Abstract

Landfills remain a prevalent method for municipal solid waste disposal, yet concerns persist regarding leachate generation and its environmental impact. This research paper investigates the reuse of end-of-life reverse osmosis membranes for treating landfill leachate (LL) after their rejuvenation. The rejuvenation process involved a specific chemical cleaning procedure that allows for permeability recovery without compromising the membrane rejection capacity when compared to o pristine reverse osmosis. It was also explored the hypothesis how previous membrane use affects the rejuvenation process by considering end-of-life membranes used for desalination of brackish water and treated water. While both could be effectively rejuvenated, those used for brackish desalination were more susceptible to irreversible fouling. In such cases, recycling the membrane and converting it to porous ultrafiltration or microfiltration membranes is recommended. For membranes previously used for treated water desalination, it was observed high efficiency in LL treatment across multiple filtration cycles. The average flux for these membranes corresponded to 6.9 ± 0.4 L/m2h (operating pressure: 10 bar), and the rejection were greater than 89.4 % for chemical oxygen demand and 98.6 % for color. In complement, it was investigated the contribution of pretreatment with ultrafiltration membranes. Ultrafiltration was effective in preventing membrane fouling and improving the physicochemical quality of reclaimed water from landfill leachate. Overall, this research provides valuable insights into the potential reuse of end-of-life reverse osmosis membranes from treated water desalination plant for LL treatment, contributing to sustainable waste management and wastewater treatment solutions.