Search results for "Clean water"
showing 10 items of 442 documents
Protein expression profiles in Bathymodiolus azoricus exposed to cadmium
2019
Proteomic changes in the "gill-bacteria complex" of the hydrothermal vent mussel B. azoricus exposed to cadmium in pressurized chambers ((Incubateurs Pressurises pour l'Observation en Culture d'Animaux Marins Profonds - IPOCAMP) were analyzed and compared with the non-exposed control group. 2-D Fluorescence Difference Gel Electrophoresis (2D-DIGE) showed that less than 1.5% of the proteome of mussels and symbiotic bacteria were affected by a short-term (24 h) Cd exposure. Twelve proteins of the more abundant differentially expressed proteins of which six were up-regulated and six were down-regulated were excised, digested and identified by mass spectrometry. The identified proteins included…
Evaluation of the Economic and Environmental Performance of Low-Temperature Heat to Power Conversion using a Reverse Electrodialysis – Multi-Effect D…
2019
In the examined heat engine, reverse electrodialysis (RED) is used to generate electricity from the salinity difference between two artificial solutions. The salinity gradient is restored through a multi-effect distillation system (MED) powered by low-temperature waste heat at 100 °C. The current work presents the first comprehensive economic and environmental analysis of this advanced concept, when varying the number of MED effects, the system sizing, the salt of the solutions, and other key parameters. The levelized cost of electricity (LCOE) has been calculated, showing that competitive solutions can be reached only when the system is at least medium to large scale. The lowest LCOE, at a…
Cost modeling for sludge and waste management from wastewater treatment plants: an empirical approach for Spain
2013
Abstract Wastewater treatment involves the generation of large volumes of sludge and other waste. Managing this waste in an economical and environmentally acceptable way has become a matter of increasing importance over the last few years. While the technologies and processes to reduce sludge generation are being widely studied, research on the economic aspects is much more limited. This study applies a cost-modeling methodology that uses statistical information from a sample of Spanish wastewater treatment plants (WWTPs) to generate a sewage sludge and waste management cost function with the aim of contributing to a better understanding of the cost structure and predicting the cost savings…
Economic feasibility study for new technological alternatives in wastewater treatment processes: a review
2012
The concept of sustainability involves the integration of economic, environmental, and social aspects and this also applies in the field of wastewater treatment. Economic feasibility studies are a key tool for selecting the most appropriate option from a set of technological proposals. Moreover, these studies are needed to assess the viability of transferring new technologies from pilot-scale to full-scale. In traditional economic feasibility studies, the benefits that have no market price, such as environmental benefits, are not considered and are therefore underestimated. To overcome this limitation, we propose a new methodology to assess the economic viability of wastewater treatment tec…
Assessment of methodologies and data used to calculate desalination costs
2017
Abstract In desalination, similarly with other industries, the cost of the final product is one of the most important criteria that define the commercial success of a specific technology. Therefore, when new projects are planned or new technologies are proposed, the analysis of the expected costs attracts a lot of attention and is compared to (perceived) costs of state-of-the-art desalination or costs of alternative fresh water supply options. This comparison only makes sense if the cost assessment methodologies are based on the same principles and use common assumptions. This paper assesses: (i) the methodologies used to calculate the water cost; (ii) the boundary conditions and (iii) the …
Analysis and simulation of scale-up potentials in reverse electrodialysis
2015
The Reverse Electrodialysis (RED) process has been widely accepted as a viable and promising technology to produce electric energy from salinity difference (salinity gradient power - e.g. using river water/seawater, or seawater and concentrated brines). Recent R&D efforts demonstrated how an appropriate design of the RED unit and a suitable selection of process conditions may crucially enhance the process performance. With this regard, a process simulator was developed and validated with experimental data collected on a lab-scale unit, providing a new modelling tool for process optimisation. In this work, performed within the REAPower project (www.reapower.eu), a process simulator previousl…
A simulation tool for analysis and design of reverse electrodialysis using concentrated brines
2015
Abstract Reverse electrodialysis (SGP-RE or RED) represents a viable technology for the conversion of the salinity gradient power into electric power. A comprehensive model is proposed for the RED process using sea or brackish water and concentrated brine as feed solutions. The goals were (i) reliably describing the physical phenomena involved in the process and (ii) providing information for optimal equipment design. For such purposes, the model has been developed at two different scales of description: a lower scale for the repeating unit of the system (cell pair), and a higher scale for the entire equipment (stack). The model was implemented in a process simulator, validated against orig…
A fuzzy-logic-based controller for methane production in anaerobic fixed-film reactors
2017
The main objective of this work was to develop a controller for biogas production in continuous anaerobic fixed-bed reactors, which used effluent total volatile fatty acids (VFA) concentration as control input in order to prevent process acidification at closed loop. To this aim, a fuzzy-logic-based control system was developed, tuned and validated in an anaerobic fixed-bed reactor at pilot scale that treated industrial winery wastewater. The proposed controller varied the flow rate of wastewater entering the system as a function of the gaseous outflow rate of methane and VFA concentration. Simulation results show that the proposed controller is capable to achieve great process stability ev…
Economic valuation of environmental benefits of removing pharmaceutical and personal care products from WWTP effluents by ozonation.
2013
Continuous release of pharmaceutical and personal care products (PPCPs) present in effluents from wastewater treatment plants (WWTPs) is nowadays leading to the adoption of specific measures within the framework of the Directive 2000/60/EC (Water Framework Directive). The ozonation process, normally employed for drinking water production, has also proven its potential to eliminate PPCPs from secondary effluents in spite of their low concentrations. However, there is a significant drawback related with the costs associated with its implementation. This lack of studies is especially pronounced regarding the economic valuation of the environmental benefits associated to avoid the discharge of …
A preliminary study on the ecotoxic potency of wastewater treatment plant sludge combining passive sampling and bioassays.
2021
Highlights • The passive samplers collected bioavail able and bioaccessible chemicals from the WWTP sludge samples. • The sampler extracts were acutely and chronically toxic to water flea. • The sampler extracts were cytotoxic and genotoxic. • The sludge treatment such as composting and digesting diminished the toxicity. • Effect-based methods should be part of the risk assessment of sludge recycling. Sewage sludge is an inevitable byproduct produced in wastewater treatment. Reusing nutrient-rich sludge will diminish the amount of waste ending in soil dumping areas and will promote circular economy. However, during sewage treatment process, several potentially harmful organic chemicals are …