Potential of Ceria-Based Catalysts for the Oxidation of Landfill Leachate by Heterogeneous Fenton Process

In this study, ceria and ceria-zirconia solid solutions were tested as catalyst for the treatment of landfill leachate with a Fenton-like process. The catalysts considered in this work were pure ceria and ceria-zirconia solid solutions as well as iron-doped samples. All the catalysts were extensively characterized and applied in batch Fenton-like reactions by a close batch system, the COD (chemical oxygen demand) and TOC (total organic carbon) parameters were carried out before and after the treatments in order to assay oxidative abatement. Results show a measurable improvement of the TOC and COD abatement using ceria-based catalysts in Fenton-like process and the best result was achieved for iron-doped ceria-zirconia solid solution. Our outcomes point out that heterogeneous Fenton technique could be effectively used for the treatment of landfill leachate and it is worth to be the object of further investigations

Characterization and BMP Tests of Liquid Substrates for High-rate Anaerobic Digestion

This work was focused on the physicochemical characterization and biochemical methane potential (BMP) tests of some liquid organic substrates, to verify if they were suitable for undergoing a process of high-velocity anaerobic digestion. The selected substrates were: first and second cheese whey, organic fraction of municipal solid waste (OFMSW) leachate, condensate water and slaughterhouse liquid waste. Firstly, a physicochemical characterization was performed, using traditional and macromolecular parameters; then, batch anaerobic tests were carried out, and some continuous tests were planned. The results revealed that all the analyzed substrates have a potential to be anaerobically treated. Valuable information about treatment rate for a high-velocity anaerobic digestion process was obtained. Start-up of a lab-scale UASB reactor, treating diluted cheese whey, was successfully achieved with good COD removal efficiency. These preliminary results are expected to be further investigated in a successive phase, where continuous tests will be conducted on condensate water and OFMSW leachate. This work is licensed under a Creative Commons Attribution 4.0 International License

Anaerobic digestion of sewage sludge: macromolecular composition and IWA ADM1 application

The aim of this study is to characterize sewage sludge (a mixture of primary and secondary sludge) coming from an anaerobic digester (AD) in order to implement the IWA Anaerobic Digestion Model no\ub01 (ADM1, Batstone et al., 2002) and to simulate the process unit behaviour. In order to estimate parameters for the ADM1 implementation and understand sludge properties, the digester was monitored for two months. Traditional chemical-physical parameters and key macromolecular compounds for anaerobic biodegradability (such as carbohydrate, proteins, lipids and volatile fatty acids) were measured samples drawn at inflow and outflow. Biomethane potential (BMP) experiments were performed in triplicate on sewage sludge and digestate. Parameters collected were used to define the influent model input adopting an ASM1/ADM1 interface (Copp\u2019s interface, Copp et al., 2003). BMP tests simulations were realized to calibrate the model, defining an operative procedure. Data set from monitoring period was used for model validation. The simulations underlined potential of AD modelling tool and the importance of macromolecular composition assessment for a correct COD\u2019s fractions and stoichiometric parameters estimate

La co-digestione anaerobica dei fanghi di depurazione e Forsu

Rassegna Tecnica del FV

Potential of Ceria-Based Catalysts for the Oxidation of Landfill Leachate by Heterogeneous Fenton Process

In this study, ceria and ceria-zirconia solid solutions were tested as catalyst for the treatment of landfill leachate with a Fenton-like process. The catalysts considered in this work were pure ceria and ceria-zirconia solid solutions as well as iron-doped samples. All the catalysts were extensively characterized and applied in batch Fenton-like reactions by a close batch system, the COD (chemical oxygen demand) and TOC (total organic carbon) parameters were carried out before and after the treatments in order to assay oxidative abatement. Results show a measurable improvement of the TOC and COD abatement using ceria-based catalysts in Fenton-like process and the best result was achieved for iron-doped ceria-zirconia solid solution. Our outcomes point out that heterogeneous Fenton technique could be effectively used for the treatment of landfill leachate and it is worth to be the object of further investigations

Potential of Ceria-Based Catalysts for the Oxidation of Landfill Leachate by Heterogeneous Fenton Process

Landfill leachate is a liquid waste of primary environmental concern because of the quantity and quality of the harmful pollutants contained in it. There are a large number of various types of organic and inorganic substances, depending on the age and type of solid wastes located in the landfill. Leachate from sanitary landfills can be an important source of ground water contamination and for this reason it is collected from the bottom of the landfill to be treated; further, this highly contaminated liquid waste accumulates a great diversity of harmful pollutants. Some of them are particularly refractory and for this reason traditional wastewater treatment plants are not efficient in their abatement. Inorganic and organic content of leachate is characteristically related to environmental risk because of scarce biodegradation, severe bioaccumulation, and potential health damages [1, 2]. It is well known that conventional biological liquid waste treatments alone are unable to achieved complete removal of the leachate pollution over the life of the landfill. In truth conventional biological processes are time consuming and low-efficiency methods to treat directly leachate, consequently physicochemical processes are frequently utilized to pretreat this liquid waste in order to reduce organic refractory before biological action in treatment plants units [3]

BMP tests of source selected OFMSW to evaluate anaerobic codigestion with sewage sludge

The aim of this study is to characterize different types of source selected organic fraction of municipal solid waste (SS-OFMSW) in order to optimize the upgrade of a sewage sludge anaerobic digestion unit by codigestion. Various SS-OFMSW samples were collected from canteens, supermarkets, restaurants, households, fruit\u2013vegetable markets and bakery shops. The substrates characterization was carried out getting traditional chemical\u2013physical parameters, performing elemental analysis and measuring fundamental anaerobic digestion macromolecular compounds such as carbohydrates, proteins, lipids and volatile fatty acids. Biochemical methane potential (BMP) tests were conducted at mesophilic temperature both on single substrates and in codigestion regime with different substrates mixing ratios. The maximum methane yield was observed for restaurant (675 NmlCH4/gVS) and canteens organic wastes (571 and 645 NmlCH4/gVS). The best codigestion BMP test has highlighted an increase of 47% in methane production respect sewage sludge digestion