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Increasing energy demands combined with local scarcities and rising prices make the valorisation of energy from domestic wastewater seen as a valuable resource. Chemically enhanced primary treatment (CEPT) enables an increased redirection of organic compounds into sludge in the primary stage of a wastewater treatment for a transformation into biogas (carbon capture). Traditionally used coagulants consist of metallic salts, but in the last two decades, the development of polymers, based on petroleum or synthesized from renewable sources such as plants, has been intensified. However, a direct comparison of the effectiveness of these products is missing. In this paper, we analysed data of peer-reviewed research from jar tests to full-scale studies, highlighting key parameters for successful carbon capture. More than 100 studies were identified, with a majority presenting results from tests under static conditions (jar tests), while data on full-scale applications are scarce. Overall, for TSS and COD, a clear correlation between inflow concentration and removal efficiency was found, irrespective of the product used. Comparison between the effectiveness of the different types of products is difficult, but bio-based coagulants need to be generally added in higher product concentrations for a considerable removal efficiency. While CEPT seems to increase the general sludge and biogas output, future studies should focus on harmonising laboratory analysis to make results comparable. Another important issue that should be addressed is the provision of experimental details, especially for full-scale trials, to enable for reliable conclusions., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Florent Chazarenc reports financial support was provided by Rhone Mediterranee Corsica Region Water Agency. Katharina Tondera reports a relationship with EUR H2O'Lyon that includes: funding grants., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The elaboration of a charter of ethics and support for the elderly, drawn up by Fabrice Gzil, places different notions of care at the center of the care of the elderly for those working in the field at the Groupe hospitalier sud Île-de-France (GHSIF). The 10 points presented are implemented on a daily basis. By highlighting these actions, the charter can be appropriated and brought to life in order to provide support adapted to the collective and individual needs of the elderly patients and residents., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

This review compiles information on sidestream characteristics that result from anaerobic digestion dewatering (conventional and preceded by a thermal hydrolysis process), biological and primary sludge thickening. The objective is to define a range of concentrations for the different characteristics found in literature and to confront them with the optimal operating conditions of sidestream processes for nutrient treatment or recovery. Each characteristic of sidestream (TSS, VSS, COD, N, P, Al 3+ , Ca 2+ , Cl - , Fe 2+/3+ , Mg 2+ , K + , Na + , SO 4 2- , heavy metals, micro-pollutants and pathogens) is discussed according to the water resource recovery facility configuration, wastewater characteristics and implications for the recovery of nitrogen and phosphorus based on current published knowledge on the processes implemented at full-scale. The thorough analysis of sidestream characteristics shows that anaerobic digestion sidestreams have the highest ammonium content compared to biological and primary sludge sidestreams. Phosphate content in anaerobic digestion sidestreams depends on the type of applied phosphorus treatment but is also highly dependent on precipitation reactions within the digester. Thermal Hydrolysis Process (THP) mainly impacts COD, N and alkalinity content in anaerobic digestion sidestreams. Surprisingly, the concentration of phosphate is not higher compared to conventional anaerobic digestion, thus offering more attractive recovery possibilities upstream of the digester rather than in sidestreams. All sidestream processes investigated in the present study (struvite, partial nitrification/anammox, ammonia stripping, membranes, bioelectrochemical system, electrodialysis, ion exchange system and algae production) suffer from residual TSS in sidestreams. Above a certain threshold, residual COD and ions can also deteriorate the performance of the process or the purity of the final nutrient-based product. This article also provides a list of characteristics to measure to help in the choice of a specific process., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

In response to the growing global resource scarcity, wastewater is increasingly seen as a valuable resource to recover and valorise for the benefit of the society rather than another waste that needs treatment before disposal. Conventional wastewater treatment plants (WWTPs) oxidise most of the organic matter present in wastewater, instead of recovering it as a feedstock for biomaterials or to produce energy in the form of biogas. In contrast, an A-Stage is capable of producing a concentrated stream of organic matter ready for valorisation, ideally suited to retrofit existing large plants. This technology is based on the principle of high-rate activated sludge process that favours biosorption and storage over oxidation. In this paper, we summarize peer-reviewed research of both pilot-scale and full-scale studies of A-Stage process under real conditions, highlighting key operational parameters. In the majority of published studies, the sludge retention time (SRT) was identified as a key operational parameter. An optimal SRT of 0.3 days seems to maximize the redirection of influent COD - up to 50% to the sludge flux, while simultaneously keeping mineralization under 25% of total influent COD. Other key optimal parameters are a hydraulic residence time of 30 min and dissolved oxygen levels of 0.5 mg⋅L - 1 . In addition, nutrient removal efficiencies of 15-27% for total nitrogen and 13-38% for total phosphorus are observed. Influence of mixing on settling efficiencies remain largely underexplored, as well as impact of wet weather flow and temperature on overall recovery efficiencies, which hinders to provide recommendations on these aspects. Evolution of modelling efforts of A-Stage process are also critically reviewed. The role of extracellular polymeric substances remain unclear and measures differ greatly according to the different studies and protocols. Better understanding the settling processes by adding Limit of Stokesian and Threshold of Flocculation measures to Sludge Volume Index could help to reach a better understanding of the A-Stage process. Reliable modelling can help new unit processes find their place in the whole treatment chain and help the transition from WWTPs towards Wastewater Resource Recovery Facilities., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)