Micro- and Nano-Plastics in Drinking Water: Threat or Hype? Critical State-of-the-Art Analysis of Risks and Approaches.

Microplastic (MP) contamination affects all environmental media, even in remote, unpopulated regions of the globe. Many studies have addressed this issue under various aspects; however, actual and definitive evidence that MPs are a cause of human health risk in actual environmental conditions has not been provided. MP decomposition generates smaller nanoplastics (NPs) with different properties, closer to engineered nanoparticles than to MP.

Anaerobic sludge digestion enhancement with bioelectrochemical and electrically conductive materials augmentation: A state of the art review.

Excess biological sludge processing and disposal have a significant impact on the energy balance and economics of wastewater treatment operations, and on receiving environments. Anaerobic digestion is probably the most widespread in-plant sludge processing method globally, since it stabilizes and converts biosolids organic matter into biogas, allowing partial recovery of their embedded chemical energy. A considerable number of studies concerning applicable techniques to improve biogas production, both in quantity and quality, include pre-treatment strategies to promote biosolids disintegration aimed at the release and solubilization of intracellular energy compounds, inorganic/biological amendments aimed at improving process performance, and sludge thermal pre-treatment.

Microplastics in the urban water cycle: A critical analysis of issues and of possible (needed?) solutions.

Microplastic (MP) contamination is a problem that affects even remote, scarcely populated regions of the world. This topic has recently been the subject of many published studies, however, these often adopt hyperbolic statements and do not actually provide definitive evidence that MPs are a cause of environmental risk in actual environmental conditions. New technologies to remove MPs from supply and waste water are being investigated, but they are able to intercept a minimal fraction of the MPs circulating in all environmental media.

Psychrophilic treatment of municipal wastewater with a combined UASB/ASD system, and perspectives for improving urban WWTP sustainability.

According to new paradigms of urban wastewater management, energy savings and resources and energy recovery from sewage will assume an ever-increasing importance. Anaerobic processes, aside from being more energy efficient than conventional aerobic ones, are particularly suited to recover embedded organic energy, improving the overall energy balance of treatment processes, however, their performance is limited by low temperatures and slower kinetics. In this study, a pilot Upflow Anaerobic Sludge Blanket (UASB) reactor was operated to treat municipal wastewater at low temperature regime (16.

Wastewater fertigation in agriculture: Issues and opportunities for improved water management and circular economy.

Water shortages are an issue of growing worldwide concern. Irrigated agriculture accounts for about 70% of total freshwater withdrawals globally, therefore alternatives to use of conventional sources need to be investigated. This paper critically reviews the application of treated wastewater for agricultural fertigation (i.

Graphitic Carbon Nitride as a Sustainable Photocatalyst Material for Pollutants Removal. State-of-the Art, Preliminary Tests and Application Perspectives.

Photocatalysis is an attractive strategy for emerging pollutants remediation. Research towards the development of new, efficient and effective catalytic materials with high activity under wide irradiation spectra is a highly active sector in material science. Various semiconductor materials have been employed as photocatalysts, including TiO, SrTiO, CdS, BiVO, TaN, TaON, AgPO, and g-CN.

Combined microalgal photobioreactor/microbial fuel cell system: Performance analysis under different process conditions.

Increasing energy demands and greenhouse gases emission from wastewater treatment processes prompted the investigation of alternatives capable to achieve effective treatment, energy and materials recovery, and reduce environmental footprint. Combination of microbial fuel cell (MFC) technology with microalgal-based process in MFC-PBR (photobioreactor) systems could reduce greenhouse gases emissions from wastewater treatment facilities, capturing CO emitted from industrial facilities or directly from the atmosphere. Microalgae production could enhance recovery of wastewater-embedded resources.

Sustainable management of biological solids in small treatment plants: overview of strategies and reuse options for a solar drying facility in Poland.

The issue of sustainable management of biosolids (excess sludge) from wastewater treatment is an important issue in the entire developed world. Residual sludge disposal costs and environmental impact may be significant, and reducing such costs, as well as the energy consumption for dewatering and drying, is a key issue for safe and sustainable sludge disposal, considering the recent ban of some disposal options, such as landfilling, in many European countries. An alternative to thermal technologies is solar drying (not to be confused with bio-drying, very close to the concept of composting).

Bioelectrochemical treatment of municipal solid waste landfill mature leachate and dairy wastewater as co-substrates.

Despite solid wastes' landfill disposal limitation due to recent European legislation, landfill leachate disposal remains a significant problem and will be for many years in the future, since its production may persist for years after a site's closure. Among process technologies proposed for its treatment, microbial fuel cells (MFCs) can be effective, achieving both contaminant removal and simultaneous energy recovery. Start-up and operation of two dual-chamber MFCs with different electrodes' structure, fed with mature municipal solid waste landfill leachate, are reported in this study.

Taking the water out of "wastewater": An ineluctable oxymoron for urban water cycle sustainability.

Water, energy, and food are key resources that could easily limit sustainability of human society development. Water supply requires considerable amounts of energy, and "usedwater" carries considerable amounts of embedded energy and recoverable materials within. Usedwater is increasingly considered as a potential resource, rather than as a waste.

In situ groundwater remediation with bioelectrochemical systems: A critical review and future perspectives.

Groundwater contamination is an ever-growing environmental issue that has attracted much and undiminished attention for the past half century. Groundwater contamination may originate from both anthropogenic (e.g.

Simulation tests of groundwater denitrification with aquifer-buried biocathodes.

Bioelectrochemical systems (BES) application was proposed for a variety of specific uses, due to these systems' characteristics: electrodes can act as virtually inexhaustible electron acceptors/donors, offering a growth-support surface for microorganisms, and stimulating naturally-occurring microbial degradation activities. groundwater denitrification therefore seems to be a potential candidate for their use. In this study, buried biocathodes were operated in laboratory settings for the simulation of groundwater denitrification.

Optimization of P compounds recovery from aerobic sludge by chemical modeling and response surface methodology combination.

Phosphorus recovery has drawn much attention during recent years, due to estimated limited available quantities, and to the harmful environmental impact that it may have when freely released into aquatic environments. Struvite precipitation from wastewater or biological sludge is among the preferred approaches applied for phosphorus recovery, as it results in the availability of valuable fertilizer materials. This process is mostly affected by pH and presence of competitive ions in solution.

Controlled sequential biocathodic denitrification for contaminated groundwater bioremediation.

Nitrate groundwater contamination is a worldwide concern. In this study, a novel 2-stage, sequential biocathodic denitrification system was tested to perform autotrophic denitrification of synthetic groundwater. The system was operated at different nitrate loading rates (66-301 gNO-N m d) at constant NO-N concentration (40 mgNO-N L), by varying hydraulic retention time (HRT) during different trials from about 14 to 3 h.

Assessment of arsenic removal efficiency by an iron oxide-coated sand filter process.

Arsenic is among the most dangerous contaminants which can limit groundwater use for drinking water consumption. Among the most diffused As-removal technologies around the world, adsorptive media systems are usually favored for relatively low cost and simplicity of operation. This study examines the performance of a laboratory-scale iron oxide-coated sand (IOCS) column filter, to remove arsenic (arsenate (As[V]) and arsenite (As[III])) from groundwater.

Evaluation of energy consumption of treating nitrate-contaminated groundwater by bioelectrochemical systems.

Nitrate contamination of groundwater is a mounting concern for drinking water production due to its healthy and ecological effects. Bioelectrochemical systems (BES) are a promising method for energy efficient nitrate removal, but its energy consumption has not been well understood. Herein, we conducted a preliminary analysis of energy consumption based on both literature information and multiple assumptions.

Comparison of different advanced degradation processes for the removal of the pharmaceutical compounds diclofenac and carbamazepine from liquid solutions.

Carbamazepine and diclofenac are two examples of drugs with widespread geographical and environmental media proliferation that are poorly removed by traditional wastewater treatment processes. Advanced oxidation processes (AOPs) have been proposed as alternative methods to remove these compounds in solution. AOPs are based on a wide class of powerful technologies, including UV radiation, ozone, hydrogen peroxide, Fenton process, catalytic wet peroxide oxidation, heterogeneous photocatalysis, electrochemical oxidation and their combinations, sonolysis, and microwaves applicable to both water and wastewater.

Industrial wastewater treatment with a bioelectrochemical process: assessment of depuration efficiency and energy production.

Development of renewable energy sources, efficient industrial processes, energy/chemicals recovery from wastes are research issues that are quite contemporary. Bioelectrochemical processes represent an eco-innovative technology for energy and resources recovery from both domestic and industrial wastewaters. The current study was conducted to: (i) assess bioelectrochemical treatability of industrial (dairy) wastewater by microbial fuel cells (MFCs); (ii) determine the effects of the applied organic loading rate (OLR) on MFC performance; (iii) identify factors responsible for reactor energy recovery losses (i.

Wastewater treatment with a new electrically enhanced biomass concentrator reactor: trial application and technological perspectives.

Biomass concentrator reactors (BCRs) are an alternative wastewater treatment technology developed as a possible solution to membrane bioreactors' (MBRs) high construction and energetic costs. BCRs are an alternative based on the same principle of biomass retention, using a coarser filter medium instead of a membrane. A BCR-derived technology enhanced by an electric field called electrically enhanced biomass concentrator reactor (EBCR) was developed, designed, and tested for wastewater treatment at different organic loads for a period of 100 days.

Can radiation chemistry supply a highly efficient AO(R)P process for organics removal from drinking and waste water? A review.

The increasing role of chemistry in industrial production and its direct and indirect impacts in everyday life create the need for continuous search and efficiency improvement of new methods for decomposition/removal of different classes of waterborne anthropogenic pollutants. This review paper addresses a highly promising class of water treatment solutions, aimed at tackling the pressing problem of emerging contaminants in natural and drinking waters and wastewater discharges. Radiation processing, a technology originating from radiation chemistry studies, has shown encouraging results in the treatment of (mainly) organic water pollution.

Feedstock and process influence on biodiesel produced from waste sewage sludge.

Disposal of sewage sludge is one of the most important issues in wastewater treatment throughout Europe, as EU sludge production, estimated at 9.5 million tons dry weight in 2005, is expected to approach 13 million tons in 2020. While sludge disposal costs may constitute 30-50% of the total operation costs of wastewater treatment processes, waste sewage sludge still contains resources that may be put to use, like nutrients and energy, that can be recovered through a variety of approaches.

Efficient degradation of MtBE and other gasoline-originated compounds by means of a biological reactor of novel conception: two case studies in Italy and the USA.

The presence of MtBE in groundwaters, due to its past use as an oxygenate additive to "green" gasoline, poses potential threats to human health as a possible carcinogen. As its chemical properties render it very mobile and poorly treatable by means of bioremediation, chemical oxidation, stripping, or carbon adsorption, a new, ex-situ treatment process was recently developed by the US EPA and the University of Cincinnati. The objective of the study was to evaluate the effectiveness of this pump-and-treat technology in actual contaminated groundwater plumes in the field in two different conditions.