Showing papers on "Effluent published in 2018"
TL;DR: In this article, a review of existing research papers on various biological, chemical and physical dye removal methods to find its efficiency through percentage of dye removal is presented, which highlights enzyme degradation and adsorption (physical) dye removal as these are known as one of the most efficient dye removal techniques these days.
Abstract: Dye effluents released from numerous dye-utilizing industries are harmful towards the environment and living things. Consequently, existence of dye effluent in environmental water bodies is becoming a growing concern to environmentalists and civilians. A long term sustainable and efficient dye effluent treatment method should be established to eliminate this issue. Dye wastewater should be treated first before release to minimize its negative impacts towards the environment and living things. However, due to lack of information on efficient dye removal methods, it is difficult to decide on a single technique that resolves the prevailing dye effluent issue. Therefore, this paper reviews existing research papers on various biological, chemical and physical dye removal methods to find its efficiency through percentage of dye removal. Although there are numerous existing tried and tested methods to accomplish dye removal, most of them have a common disadvantage which is the generation of secondary pollution to the environment. This paper highlights enzyme degradation (biological) and adsorption (physical) dye removal as these are known as one of the most efficient dye removal techniques these days. This paper also suggests the usage of a combined adsorbent as it is envisioned that this technique has better efficiency and is able to remove dyes at a faster rate.
1,186 citations
TL;DR: This study proves the potential of novel nonmetal porous photocatalyst to simultaneously treat wastewater while converting solar energy into clean hydrogen energy.
426 citations
TL;DR: An overall picture about the current status of MPs in WWTPs across China is drawn and provides useful information for better control of the risks associated with MPs.
258 citations
TL;DR: This study constructed a 1000 L modularized MFC system, the largest volume so far, to treat practical municipal wastewater, which stably met the level A of the first class in discharge standard of pollutants for MWTP of China.
232 citations
TL;DR: Wetland behavior and efficiency concerning wastewater treatment is mainly linked to macrophyte composition, substrate, hydrology, surface loading rate, influent feeding mode, microorganism availability, and temperature, and constructed wetlands were concluded to be the most suitable ones in terms of pollutant removal and have advantages due to both low maintenance costs and required energy.
Abstract: Due to water scarcity challenges around the world, it is essential to think about non-conventional water resources to address the increased demand in clean freshwater. Environmental and public health problems may result from insufficient provision of sanitation and wastewater disposal facilities. Because of this, wastewater treatment and recycling methods will be vital to provide sufficient freshwater in the coming decades, since water resources are limited and more than 70% of water are consumed for irrigation purposes. Therefore, the application of treated wastewater for agricultural irrigation has much potential, especially when incorporating the reuse of nutrients like nitrogen and phosphorous, which are essential for plant production. Among the current treatment technologies applied in urban wastewater reuse for irrigation, wetlands were concluded to be the one of the most suitable ones in terms of pollutant removal and have advantages due to both low maintenance costs and required energy. Wetland behavior and efficiency concerning wastewater treatment is mainly linked to macrophyte composition, substrate, hydrology, surface loading rate, influent feeding mode, microorganism availability, and temperature. Constructed wetlands are very effective in removing organics and suspended solids, whereas the removal of nitrogen is relatively low, but could be improved by using a combination of various types of constructed wetlands meeting the irrigation reuse standards. The removal of phosphorus is usually low, unless special media with high sorption capacity are used. Pathogen removal from wetland effluent to meet irrigation reuse standards is a challenge unless supplementary lagoons or hybrid wetland systems are used.
193 citations
191 citations
TL;DR: The study was aimed to develop a cost effective and ecofriendly method of textile waste treatment using native soil bacterium, identified as Arthrobacter soli BS5 by 16S rDNA sequencing that showed remarkable ability to degrade a textile dye reactive black 5 with maximum degradation of 98% at 37 °C and pH in the range of 5–9 after 120 h of incubation.
Abstract: Water pollution caused by the discharge of hazardous textile effluents is a serious environmental problem worldwide. In order to assess the pollution level of the textile effluents, various physico-chemical parameters were analyzed in the textile wastewater and agricultural soil irrigated with the wastewater (contaminated soil) using atomic absorption spectrophotometer and gas chromatography-mass spectrometry (GC-MS) analysis that demonstrated the presence of several toxic heavy metals (Ni, Cu, Cr, Pb, Cd, and Zn) and a large number of organic compounds. Further, in order to get a comprehensive idea about the toxicity exerted by the textile effluent, mung bean seed germination test was performed that indicated the reduction in percent seed germination and radicle-plumule growth. The culturable microbial populations were also enumerated and found to be significantly lower in the wastewater and contaminated soil than the ground water irrigated soil, thus indicating the biotic homogenization of indigenous microflora. Therefore, the study was aimed to develop a cost effective and ecofriendly method of textile waste treatment using native soil bacterium, identified as Arthrobacter soli BS5 by 16S rDNA sequencing that showed remarkable ability to degrade a textile dye reactive black 5 with maximum degradation of 98% at 37 °C and pH in the range of 5–9 after 120 h of incubation.
181 citations
TL;DR: Data on the occurrence of pharmaceuticals reported in this paper are the basis for current studies that aim to develop efficient systems for the degradation/removal of these compounds from the aquatic environment.
180 citations
TL;DR: The efficiency of the microalgae technology removing PhACs was found to be comparable to that used in conventional WWTPs, and shows the potential of HRAP technology for wastewater treatment as an alternative (or addition as tertiary treatment) to more conventional approaches based on activated sludge.
165 citations
TL;DR: The results suggest that the studied WWTPs mostly succeed in decreasing the host range of the resistance genes during the treatment process, although there were instances where effluent contained resistance genes in bacterial groups not carrying these genes in the influent.
156 citations
TL;DR: The continued detection of PFOA and PFOS over a decade after its phase out, the increasing use of PFOS alternatives together with their resistance to degradation processes suggests that PFASs will be a priority for regulators and waste management to prevent further contamination of Australia's water resources.
TL;DR: Canonical correspondence analysis based on the results of next-generation sequencing showed that the time of adaptation significantly influenced the microbial composition of the granules, and molecular data given here provide insight into the ecology of mature aerobic granules from a full-scale facility.
Abstract: By modification of the operational conditions of batch reactors, a municipal wastewater treatment plant was upgraded from activated sludge to aerobic granular sludge (AGS) technology. After upgrading, the volume of the biological reactors was reduced by 30%, but the quality of the effluent substantially improved. The concentration of biomass in the reactors increased twofold; the average biomass yield was 0.6 g MLVSS/g COD, and excess granular sludge was efficiently stabilized in aerobic conditions. Canonical correspondence analysis based on the results of next-generation sequencing showed that the time of adaptation significantly influenced the microbial composition of the granules. In mature granules, the abundance of ammonium-oxidizing bacteria was very low, while the abundance of the nitrite-oxidizing bacteria Nitrospira sp. was 0.5 ± 0.1%. The core genera were Tetrasphaera, Sphingopyxis, Dechloromonas, Flavobacterium, and Ohtaekwangia. Bacteria belonging to these genera produce extracellular polymeric substances, which stabilize granule structure and accumulate phosphorus. The results of this study will be useful for designers of AGS wastewater treatment plants, and molecular data given here provide insight into the ecology of mature aerobic granules from a full-scale facility.
TL;DR: In this article, the authors focus on the emergence of antibiotic resistance in waste water, waste water treatment, challenges and their impact on human health and conclude that the improvements in wastewater treatment technologies are required that not only remove solids, organic matter, and nutrients but also they could remove AR element and bacteria.
Abstract: The spread of bacterial antibiotic resistance (due to over and non-judicious use of antibiotics) is an apprehensive subjects matter and the role of wastewater treatment plants has been attracting particular interest. These stations are a reservoir of resistant bacteria, and the amount of bacteria released into the environment is very high and dangerous. The reuse of treated wastewater for irrigation is a practical solution for surmounting scarcity of water, but there are several health-related and environmental risks associated with this practice. It may increase antibiotic resistance (AR) levels in soil and water. Wastewater treatment plant effluents have been recognised as significant environmental AR reservoirs due to selective pressure generated by antibiotics that are frequently discharged in water. It also enhanced the possibility of horizontal gene transfer by increasing the abundance of the resistance gene. This review focuses on the emergence of antibiotic resistance in waste water, waste water treatment, challenges and their impact on human health. Based on the current state of the art, we conclude that the improvements in wastewater treatment technologies are required that not only remove solids, organic matter, and nutrients but also they could remove AR element and bacteria.
TL;DR: The use of reclaimed wastewater for irrigation is foreseen as a possible strategy to mitigate the pressure on water resources in dry regions, but there is the risk of potential accumulation of contaminants of emerging concern in the edaphic environment, their percolation and consequently contamination of aquifers.
TL;DR: In this paper, the microplastic concentrations of the influent and secondary effluent water of two wastewater treatment plants in Turkey were determined both visually and using μ-Raman spectroscopy.
Abstract: Wastewater treatment plants are one of the primary pathways through which microplastics enter aquatic environments. In this study, we have determined the microplastic concentrations of the influent and secondary effluent water of two wastewater treatment plants in Turkey. For this purpose, we have taken samples of the influent and effluent water of Seyhan and Yuregir wastewater treatment facilities for 6 days in August 2017 and determined their microplastics’ content both visually and using μ-Raman spectroscopy. The results showed that the influent of the wastewater treatment contained 1 million–6.5 million particles per day, while the effluent contained 220,000–1.5 million particles per day. The removal rate of microplastics was found to be between 73 and 79%. In total, seven different types of polymers were detected. The most frequently observed polymer type was polyester.
TL;DR: The genetic footprint, including genes specific to antibiotic resistance and mobile genetic elements and their associated organisms, are tracked, from WWTPs to lake sediments, suggesting a substantial influence of wastewater effluent on gene content and microbial community structure in the sediments of receiving water bodies.
Abstract: Wastewater treatment plants (WWTPs) release treated effluent containing mobile genetic elements (MGEs), antibiotic resistance genes (ARGs), and microorganisms into the environment, yet little is known about their influence on nearby microbial communities and the retention of these factors in receiving water bodies. Our research aimed to characterize the genes and organisms from two different WWTPs that discharge into Lake Michigan, as well as from surrounding lake sediments to determine the dispersal and fate of these factors with respect to distance from the effluent outfall. Shotgun metagenomics coupled to distance-decay analyses showed a higher abundance of genes identical to those in WWTP effluent genes in sediments closer to outfall sites than in sediments farther away, indicating their possible WWTP origin. We also found genes attributed to organisms, such as those belonging to Helicobacteraceae, Legionellaceae, Moraxellaceae, and Neisseriaceae, in effluent from both WWTPs and decreasing in abundance in lake sediments with increased distance from WWTPs. Moreover, our results showed that the WWTPs likely influence the ARG composition in lake sediments close to the effluent discharge. Many of these ARGs were located on MGEs in both the effluent and sediment samples, indicating a relatively broad propensity for horizontal gene transfer (HGT). Our approach allowed us to specifically link genes to organisms and their genetic context, providing insight into WWTP impacts on natural microbial communities. Overall, our results suggest a substantial influence of wastewater effluent on gene content and microbial community structure in the sediments of receiving water bodies. IMPORTANCE Wastewater treatment plants (WWTPs) release their effluent into aquatic environments. Although treated, effluent retains many genes and microorganisms that have the potential to influence the receiving water in ways that are poorly understood. Here, we tracked the genetic footprint, including genes specific to antibiotic resistance and mobile genetic elements and their associated organisms, from WWTPs to lake sediments. Our work is novel in that we used metagenomic data sets to comprehensively evaluate total gene content and the genetic and taxonomic context of specific genes in environmental samples putatively impacted by WWTP inputs. Based on two different WWTPs with different treatment processes, our findings point to an influence of WWTPs on the presence, abundance, and composition of these factors in the environment.
TL;DR: There were significant differences in the concentrations of ciprofloxacin, azithromycin, and erythromycin in Firozabad ditch and Kan River which demonstrated that WWTPs discharges could be an important source of antibiotics being released in water bodies.
TL;DR: Treatment of textile dyeing industry (TDI) effluent was investigated using hydrodynamic cavitation (HC) and in combination with advanced oxidation reagents such as air, oxygen, ozone and Fenton's reagent to evaluate efficiency of the hybrid treatment processes.
TL;DR: This pilot-scale study demonstrates that the E-peroxone process can provide a feasible, effective, and energy-efficient alternative for micropollutant abatement and bromate control in water and wastewater treatment.
TL;DR: In this review, the available literature on the mechanisms involved in granulation and how it affects the effluent quality is assessed with special attention given to the microbial interactions involved.
Abstract: Granular activated sludge has gained increasing interest due to its potential in treating wastewater in a compact and efficient way. It is well-established that activated sludge can form granules under certain environmental conditions such as batch-wise operation with feast-famine feeding, high hydrodynamic shear forces, and short settling time which select for dense microbial aggregates. Aerobic granules with stable structure and functionality have been obtained with a range of different wastewaters seeded with different sources of sludge at different operational conditions, but the microbial communities developed differed substantially. In spite of this, granule instability occurs. In this review, the available literature on the mechanisms involved in granulation and how it affects the effluent quality is assessed with special attention given to the microbial interactions involved. To be able to optimize the process further, more knowledge is needed regarding the influence of microbial communities and their metabolism on granule stability and functionality. Studies performed at conditions similar to full-scale such as fluctuation in organic loading rate, hydrodynamic conditions, temperature, incoming particles, and feed water microorganisms need further investigations.
TL;DR: Investigation of whether the addition of magnetite could help reactors treating MSW incineration leachate overcome limitations and promote efficient conversion of complex organic matter to methane showed that magnetite amendments improved chemical oxygen demand (COD) removal efficiencies and methane production rates.
TL;DR: In this paper, the authors reviewed the technologies implemented for removal of ammonia and its associated compounds from wastewater based on physicochemical methods and biochemical treatment methods like biological treatment, membrane filtration, ion exchange, chemical precipitation, adsorption and some other technologies such as photocatalytic oxidation, aeration, and air stripping.
TL;DR: An increase in influent flux and influent particle concentration corresponds with increasing TMP and filtration resistance, as well as a rapid reduction in effluent turbidity due to swift formation of a DM on the supporting mesh.
TL;DR: In this paper, the main pollutants in the photovoltaic cells manufacturing effluent were removed by electrodialysis application, and the results obtained can be used to optimize the pollutant removal recovery at large scale.
TL;DR: Life cycle environmental impacts of the following advanced treatment techniques aimed at reducing freshwater ecotoxicity potential of PPCPs are considered: granular activated carbon (GAC), nanofiltration (NF), solar photo-Fenton (SPF) and ozonation.
TL;DR: This study demonstrated the feasibility to integrate mainstream anammox into an A-2B process for municipal wastewater treatment towards energy-efficient operation with reduced sludge production.
01 Jan 2018
TL;DR: The results showed that the influent of the wastewater treatment contained 1 million–6.5 million particles per day, while the effluent contained 220,000–1.5 billion particles, and the removal rate of microplastics was found to be between 73 and 79%.
TL;DR: In this paper, the authors proposed an ensemble of fuzzy logic models as surrogates for the Tabriz wastewater treatment plant (TWWTP) to avoid simulating complex physical, chemical, and biological treatment processes.
TL;DR: Results of presented study demonstrate high efficiency of ARB and ARGs removal during the wastewater treatment processes, especially by WWTPs with MB and MB-ERN systems, and EFF is still an important reservoir of ARGs which can be transferred to other microorganisms.
TL;DR: In this article, a UVC-assisted photo-Fenton process was applied to hospital wastewater that had been submitted to anaerobic treatment, which quantitatively reduced the biochemical oxygen demand, chemical oxygen demand (COD), and total organic carbon (TOC), with low removal of antibiotics present in the wastewater.
Abstract: A UVC-assisted photo-Fenton process was applied to hospital wastewater that had been submitted to anaerobic treatment. Low iron (10 μM; 0.56 mg L−1) and H2O2 (500 μM; 17 mg L−1) concentrations were used at the natural pH of the effluent (pH ≈ 7.4). Citric acid was employed as a complexation agent, at a 1:1 ratio, in order to maintain Fe3+ soluble at this pH, avoiding extra procedures and costs associated with acidification/basification of the final effluent. The anaerobic process quantitatively reduced the biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and total organic carbon (TOC), with low removal of antibiotics present in the wastewater. Degradation of the antibiotics ciprofloxacin, amoxicillin, sulfathiazole, and sulfamethazine was studied by spiking the anaerobic effluent at initial concentrations of 200 μg L−1. The antibiotics were efficiently degraded (80–95%) using UVC radiation alone, although under this condition, no DOC removal was observed after 90 min. Further additions of H2O2 and iron citrate increased the degradation rate constant (kobs), and 8% of DOC was removed. A lower pH resulted in higher kobs, although this was not essential for application of the photo-Fenton process. Irradiation with a germicidal lamp resulted in greater degradation of the antibiotics, compared to use of a black light lamp or sunlight, since the overall degradation was influenced by photolysis of the antibiotics, photolysis of H2O2, and the Fenton reaction. The photo-Fenton treatment could also be applied directly to the raw hospital wastewater, since no significant difference in degradation of the antibiotics was observed, compared to the anaerobic effluent. The photo-Fenton process under UVA and solar radiation reduced total coliforms and E. coli after 90 min. However, quantitative disinfection of these bacteria present in the Hospital effluent was only accomplished under UVC radiation.