Advanced Oxidation Processes: Process Mechanisms, Affecting Parameters and Landfill Leachate Treatment

Abstract

Advanced oxidation processes (AOPs) are of special interest in treating landfill leachate as they are the most promising procedures to degrade recalcitrant compounds and improve the biodegradability of wastewater. This paper aims to refresh the information base of AOPs and to discover the research gaps of AOPs in landfill leachate treatment. A brief overview of mechanisms involving in AOPs including ozone-based AOPs, hydrogen peroxide-based AOPs and persulfate-based AOPs are presented, and the parameters affecting AOPs are elaborated. Particularly, the advancement of AOPs in landfill leachate treatment is compared and discussed. Landfill leachate characterization prior to method selection and method optimization prior to treatment are necessary, as the performance and practicability of AOPs are influenced by leachate matrixes and treatment cost. More studies concerning the scavenging effects of leachate matrixes towards AOPs, as well as the persulfate-based AOPs in landfill leachate treatment, are necessary in the future.

Assessment of Phytotoxicity in Untreated and Electrochemically Treated Leachates through the Analysis of Early Seed Growth and Inductively Coupled Plasma-Optical Emission Spectroscopy Characterization

“…The TC was determined as the ratio of the metal concentration in the root to its content in the soil (mg kg −1 ) (Equation ( 5)) [67]. TC = Plant root metal concentration/Soil metal concentration (5) The EnC quantifies the ability of the plant to accumulate soil metals. The EnC is a metric used to evaluate the degree of soil contamination and metal accumulation in plants cultivated in polluted soil, relative to plants and soil in a control environment.…”

“…Untreated leachates have the potential to inflict severe and irreversible harm on both aquatic and terrestrial ecosystems [1]. The categorization of leachates is based on their age, which can be classified as young (less than 5 years), intermediate (5-10 years), or stabilized (>10 years), as reported by Kow et al [5]. For the biological treatment of leachates, the ideal BOD 5 /COD ratio is >0.5 [6], but previous investigations conducted by our group have determined that the biodegradability index (BOD 5 /COD ratio) of the leachates used in this project (Bordo Poniente landfill, Mexico City, México) was 0.094 ± 0.03 [7,8].…”

Determination of the effectiveness of the electrocoagulation process in the treatment of leachate from the controlled landfill site in Francisco de Orellana canton

“…Leachate from landfills is grouped into three categories according to its age: young (less than 5 years), intermediate (between 5 and 10 years), and old (more than 10 years), based on how long it has been in the landfill site 9,10 . Young leachate from landfills tends to have a BOD/COD ratio greater than 0.5, while old leachate tends to be less than 0.1 11 .…”

Research Progress of Iron-Based Catalysts in Ozonation Wastewater Treatment

“…The advanced oxidation methods (AOPs) have been warmly welcomed for their high removal efficiency, especially in the treatment of refractory organic wastewater. Hydroxyl radicals play a dominant role in the reaction of AOPs. , Among them, the Fenton/light-Fenton method, , ozone oxidation method, , wet air oxidation method (WAO), , electric coagulation method, , and photocatalytic oxidation method − are widely employed. Ozone oxidation is the use of ozone as an oxidant to degrade difficult organic pollutants in wastewater.…”

“…Hydroxyl radicals play a dominant role in the reaction of AOPs. 7,8 Among them, the Fenton/light-Fenton method, 9,10 ozone oxidation method, 11,12 wet air oxidation method (WAO), 13,14 coagulation method, 15,16 and photocatalytic oxidation method 17−19 are widely employed. Ozone oxidation is the use of ozone as an oxidant to degrade difficult organic pollutants in wastewater.…”