Search results for "Wastewater"
showing 10 items of 718 documents
Valorization of winery and oil mill wastes by microbial technologies
2015
Agro-food industrial wastes represent a serious environmental problem in producing countries. In addition to the traditional irrigation with wastewaters, application of solids to the land, and the extraction of valuable compounds for the pharmaceutical, cosmetics and food industries, a microbiological approach is also available. In this review, the most promising microbiological processes for the valorization of wine and oil by-products are presented. Recently, there has been an upsurge in the exploitation of the waste materials generated by the wine and olive oil industries. Treatments by physical and chemical methods are generally expensive, and they do not often provide complete solution…
Energy harvesting by waste acid/base neutralization via bipolar membrane reverse electrodialysis
2020
Bipolar Membrane Reverse Electrodialysis (BMRED) can be used to produce electricity exploiting acid-base neutralization, thus representing a valuable route in reusing waste streams. The present work investigates the performance of a lab-scale BMRED module under several operating conditions. By feeding the stack with 1 M HCl and NaOH streams, a maximum power density of ~17 W m−2 was obtained at 100 A m−2 with a 10-triplet stack with a flow velocity of 1 cm s−1, while an energy density of ~10 kWh m−3 acid could be extracted by a complete neutralization. Parasitic currents along feed and drain manifolds significantly affected the performance of the stack when equipped with a higher number of t…
Electrodialysis for wastewater treatment—Part I: Fundamentals and municipal effluents
2020
Abstract Selectivity, high recovery, and chemical-free operation are strengths of electrodialysis. Different configurations have been proposed for several applications. Effluents from municipal wastewater treatment plants (including sludge and supernatants), desalination plants, and animal farms can be treated for recovering water, nutrients, salts, and acids/bases. Although many applications are technoeconomically feasible and competitive with other zero liquid discharge systems, only a few real plants have been installed. However, the research is currently very active, thus paving the way for a widespread use at large scale in the next future.
Soil DNA evidence for altered microbial diversity after long-term application of municipal wastewater
2010
International audience; Water resources constitute a social, agricultural and economic problem in most countries of the southern Mediterranean Basin. Alternative strategies have been developed such as the reuse of municipal wastewater for irrigation in agriculture. Despite numerous advantages for soil fertility and crop productivity, recycling wastewater in soils also has several ecotoxicological and sanitary problems. Few investigations have assessed the risk by evaluating the impact of wastewater irrigation on soil microbes. Here, we report for the first time the short- and long-term effects of treated municipal wastewater irrigation on the density and genetic structure of bacterial and f…
Impact assessment of irrigation by treated wastewater on soil bacterial genetic structure diversity of Nabeul-Tunisia irrigated areas
2011
Affiche, résumé. Session AS: Agricullural Soils: Biodiverslly and Functloning; International audience
Removal of selected antibiotics and antiretroviral drugs during post‐treatment of municipal wastewater with UV, UV/chlorine and UV/hydrogen peroxide
2020
Active pharmaceutical ingredients (APIs) are only partially removed by convectional wastewater treatment plants. This study aimed at assessing the post‐treatment degradation of selected antibiotics and antiretroviral drugs by direct UV photolysis and advanced oxidation processes (UV/H2O2 and UV/Cl2) using low‐pressure mercury lamp. The rate of degradation largely followed pseudo first‐order reaction kinetics. Amongst the six studied APIs, sulfamethoxazole, ciprofloxacin and zidovudine were readily degraded by more than 90% using direct UV photolysis. Addition of Cl2 and H2O2 to the UV process led to an increase in the rate of degradation for all the compounds. The effectiveness UV/Cl2 proce…
Ultrasound assisted method to increase soluble chemical oxygen demand (SCOD) of sewage sludge for digestion
2004
The aim of this study was to clarify the possibilities to increase the amount of soluble chemical oxygen demand (SCOD) and methane production of sludge using ultrasound technologies with and without oxidising agents. The study was done using multivariate data analyses. The most important factors affected were discovered. Ultrasonically assisted disintegration increased clearly the amount of SCOD of sludge. Also more methane was produced from treated sludge in anaerobic batch assays compared to the sludge with no ultrasonic treatment. Multivariate data analysis showed that ultrasonic power, dry solid content of sludge (DS), sludge temperature and ultrasonic treatment time have the most signi…
Disintegration of Wastewater Activated Sludge (WAS) for Improved Biogas Production
2018
Due to rapid urbanization, the number of wastewater treatment plants (WWTP) has increased, and so has the associated waste generated by them. Sustainable management of this waste can lead to the creation of energy-rich biogas via fermentation processes. This review presents recent advances in the anaerobic digestion processes that have led to greater biogas production. Disintegration techniques for enhancing the fermentation of waste activated sludge can be apportioned into biological, physical and chemical means, which are included in this review; they were mainly compared and contrasted in terms of the ensuing biogas yield. It was found that ultrasonic- and microwave-assisted disintegrati…
Environmental assessment of the Sibiu County, Romania: proposal for sewage sludge and OFMSW management
2017
The aim of the work is to assess current solid waste management (SWM) and wastewater treatment (WWT) in the county of Sibiu, Romania. Sibiu is a region where industrialization and tourism are spreading constantly, while pollution monitoring and the introduction of circular economy (CE) principles are still lacking. The environmental issues are mostly due to the absence of reliable sanitation systems, in particular for what concerns sewage sludge treatment. Moreover, Organic fraction from selective collection of municipal solid waste is still missing, since it is disposed of directly to landfill, increasing environmental pollution and contributing considerably to global warming. As a result,…
Development and pilot-scale validation of a fuzzy-logic control system for optimization of methane production in fixed-bed reactors
2018
International audience; The objective of this study was to develop an advanced control system for optimizing the performance of fixed-bed anaerobic reactors. The controller aimed at maximizing the bio-methane production whilst controlling the volatile fatty acids content in the effluent. For this purpose, a fuzzy-logic controller was developed, tuned and validated in an anaerobic fixed-bed reactor at pilot scale (350 L) treating raw winery wastewater. The results showed that the controller was able to adequately optimize the process performance, maximizing the methane production in terms of methane flow rate, resulting in an average methane yield of about 0.29 LCH4 g−1 COD. On the other han…