Search results for " wastewater"

Design methodology for submerged anaerobic membrane bioreactors (AnMBR): A case study

2015

[EN] The main objective of this study is to propose guidelines for designing submerged anaerobic MBR (AnMBR) technology for municipal wastewater treatment. The design methodology was devised on the basis of simulation and experimental results from an AnMBR plant featuring industrial-scale hollow-fibre membranes. The proposed methodology aims to minimise both capital expenditure and operating expenses, and the key parameters considered were: hydraulic retention time, solids retention time, mixed liquor suspended solids concentration in the membrane tank, 20 C-standardised critical flux, specificgas demand per square metre of membrane area, and flow of sludge being recycled from the membrane …

Mathematical protocols for calibration of wastewater treatment models

2015

Activated sludge models can be very useful for designing and managing wastewater treatment plants (WWTPs). However, as with every model, they need to be calibrated for correct and reliable application. Activated sludge model calibration is still a crucial point that needs appropriate guidance. Indeed, although calibration protocols have been developed, the model calibration still represents the main bottleneck to modelling. This abstract shows a procedure for the calibration of an activated sludge model based on a comprehensive sensitivity analysis and a novel step-wise Monte Carlo-based calibration of the subset of influential parameters. The key point of the step-wise procedure is that ca…

The Carini experimental station for wastewater reuse in agricolture.

1992

Aerobic granular sludge treating high strength citrus wastewater: Analysis of pH and organic loading rate effect on kinetics, performance and stabili…

2017

Abstract In the present paper, the feasibility of citrus wastewater treatment with aerobic granular sludge sequencing batch reactors (AGSBR) was investigated. Two AGSBRs (named R1 and R2, respectively) were operated for 90 days under different organic loading rates (OLR) and pH in two experimental periods. The OLR ranged approximately between 3.0 kg TCOD m−3d−1 and 7 kg TCOD m−3d−1 during Period I, whereas between 7 kg TCOD m−3d−1 and 15 kg TCOD m−3d−1 during Period II. pH was maintained at 7.0 and 5.5 in R1 and R2, respectively. The results revealed that under high OLR and unbalanced feast/famine regime (Period I), the development of fast-growing microorganisms (fungi and filamentous bacte…

Wastewaters from citrus processing industry as natural biostimulants for soil microbial community

2020

Abstract Citrus fruit processing wastewaters (CWWs), being rich in organic matter, may be a valuable resource for agricultural irrigation and, possibly, for the improvement of soil organic carbon (TOC). This issue is becoming crucial for soils of arid and semiarid environments increasingly experiencing water scarcity and continuous decline of TOC towards levels insufficient to sustain crop production. However, before using CWWs in agriculture their effects on the soil living component have to be clarified. Therefore, in this study we assessed the impact of CWWs on soil chemical and biochemical properties. Under laboratory conditions, lemon, orange and tangerine wastewaters were separately a…

Challenges and opportunities for citrus wastewater management and valorisation: A review.

2022

Citrus wastewaters (CWWs) are by-products of the citrus fruit transformation process. Currently, more than 700 million of m³ of CWWs per year are produced worldwide. Until nowadays, the management of CWWs is based on a take-make-use-dispose model. Indeed, after being produced within a citrus processing industry, CWWs are subjected to treatment and then discharged into the environment. Now, the European Union is pushing towards a take-make-use-reuse management model, which suggests to provide for the minimization of residual pollutants simultaneously with their exploitation through a biorefinery concept. Indeed, the recovery of energy nutrients and other value-added products held by CWWs may…

The Membrane-Less Microbial Fuel Cell (ML-MFC) with Ni-Co and Cu-B Cathode Powered by the Process Wastewater from Yeast Production

2020

Research related to measurements of electricity production was combined with parallel wastewater parameter reduction in a membrane-less microbial fuel cell (ML-MFC) fed with industry process wastewater (from a yeast factory). Electrodes with Ni–Co and Cu–B catalysts were used as cathodes. A carbon electrode (carbon cloth) was used as a reference due to its widespread use. It was demonstrated that all analyzed electrodes could be employed as cathodes in ML-MFC fed with process wastewater from yeast production. Electricity measurements during ML-MFC operations indicated that power (6.19 mW) and current density (0.38 mA·cm−2) were the highest for Ni–Co electrodes. In addition, during the explo…

Biodegradation of Synthetic Organic Compounds by Methanogenic Microbiome as an Alternative Approach for Wastewater Purification and Energy Production

2022

The use of fossil fuels (methane, oil, etc.) is undergoing an unprecedented crisis now. There is the urgent need to search for alternative energy sources. A wide range of degraded organic materials can be effectively used to provide energy together with environmental protection. Soapstock is a hazardous waste containing a high concentration of toxic organic compounds of man-made origin (fatty acids, surfactants, dyes, etc.). To prevent environmental contamination such substances require an effective treatment approach. The goal of the study was to isolate the adapted-to-fatty-acids methanogenic microbiome and investigate the patterns of sodium acetate and soapstock degradation with simultan…

Performance of a Pilot-Scale Constructed Wetland and Medium-Term Effects of Treated Wastewater Irrigation of Arundo donax L. on Soil and Plant Parame…

2021

On marginal lands in the Mediterranean basin, giant reed (Arundo donax L.) represents one of the most interesting perennial crops due to high levels of biomass production. Considering periodic water shortage during the summer months in this area, the reuse of treated wastewater (TWW) would seem to be a good opportunity for the growth of the species. The aim of this study was to assess the medium-term effects of irrigation using freshwater (FW) and TWW on soil characteristics and growth in giant reed plants. TWW was obtained from a pilot-scale horizontal subsurface flow constructed wetland system (HSSF CWs) with a total surface area of 100 m2. A split-plot design for a two-factor experiment …

Genetic potential, diversity and activity of an atrazine-degrading community enriched from a herbicide factory effluent

2008

Aims:  To characterize an atrazine-degrading bacterial community enriched from the wastewater of a herbicide factory. Methods and Results:  The community mineralized 81·4 ± 1·9% of [14C-ring]atrazine and 31·0 ± 1·8% of [14C-ethyl]atrazine within 6 days of batch cultivation in mineral salts medium containing atrazine as the sole nitrogen source. Degradation activity of the community towards different chloro- and methylthio-substituted s-triazine compounds was also demonstrated. Restriction analysis of amplified 16S rDNA revealed high diversity of bacterial populations forming the community, with Pseudomonas species dominating in the clone library. Atrazine-degrading genetic potential of the …