UVA-LED Technology’s Treatment Efficiency and Cost in a Competitive Trial Applied to the Photo-Fenton Treatment of Landfill Leachate

Abstract

The objective of this trial was to assess the application of UVA-LED technology as an alternative source of irradiation for photo-Fenton processes, aiming to reduce treatment costs and provide a feasible treatment for landfill leachate. An optimized combination of coagulation with ferric chloride followed by photo-Fenton treatment of landfill leachate was optimized. Three different radiation sources were tested, namely, two conventional high-pressure mercury-vapor immersion lamps (100 W and 450 W) and a custom-designed 8 W 365 nm UVA-LED lamp. The proposed treatment combination resulted in very efficient degradation of landfill leachate (COD removal = 90%). The coagulation pre-treatment removed about 70% of the COD and provided the necessary amount of iron for the subsequent photo-Fenton treatment, and it further favored this process by acidifying the solution to an optimum initial pH of 2.8. The 90% removal of color improved the penetration of radiation into the medium and by extension improved treatment efficiency. The faster the Fenton reactions were, as determined by the stoichiometric optimum set-up reaction condition of [H2O2]0/COD0 = 2.125, the better were the treatment results in terms of COD removal and biodegradability enhancement because the chances to scavenge oxidant agents were limited. The 100 W lamp was the least efficient one in terms of final effluent quality and operational cost figures. UVA-LED technology, assessed as the application of an 8 W 365 nm lamp, provided competitive results in terms of COD removal, biodegradability enhancement, and operational costs (35–55%) when compared to the performance of the 450 W conventional lamp.

Pretreatment of Landfill Leachate Using Hydrodynamic Cavitation at Basic pH Condition

“…The decline in NH 3 -N with time could be attributed to air stripping and oxidation, and its rise could be attributed to the fact that the amino groups attached to the organic matters were oxidized to ammonium salts, which existed in the effluent as ammonium ions [46].…”

Optimization Approach to Evaluate the Solar, UV and LED Visible Light Fenton Processes for Pollutant Degradation in Landfill Leachate

“…The study was carried out on Fenton process for landfill leachate using two standard high-pressure mercury-vapor immersion lamps (100 W and 450 W) and a specially made 8 W 365 nm UVA-LED lamp (Tejera et al, 2021). With an 8 W 365 nm UVA-LED lamp, COD could be removed 90%, whereas high pressure mercury vapour immersion lamps demonstrated poor COD removal.…”

Micro- and Macroelements Content of Plants Used for Landfill Leachate Treatment Based on Phragmites australis and Ceratophyllum demersum

“…Among the methods used to treat leachate from landfills, biological, chemical and physical ones can be distinguished. Physical and chemical methods (e.g., coagulation/flocculation, membrane treatment or chemical precipitation) are recommended mainly in the treatment of mature leachate with low biodegradability [18]. However, biological methods are recommended for young leachates due to their high biodegradability.…”