Potential of the Constructed Wetlands and the Earthworm-Based Treatment Technologies to Remove the Emerging Contaminants: A Review

Water scarcity is one of the main problems of this century. Water reclamation appears as an alternative due to the reuse of treated wastewater. Therefore, effluents treatment technologies (activated sludge, rotary biological discs, percolating beds) must be improved since they are not able to remove emerging contaminants such as enteric pathogens (bacteria and virus). These pollutants are difficult to remove from the wastewater and lead to adverse consequences to human health. Advanced oxidation processes, such as single and catalytic ozonation, appear as suitable complements to conventional processes. Catalytic ozonation was carried out using a low-cost material, a volcanic rock. Single and catalytic ozonation were capable of promoting total Escherichia coli removal from municipal wastewater after 90 min of contact. The presence of volcanic rock increases disinfection efficiency since E. coli regrowth was not observed. The identified viruses (Norovirus genotype I and II and JC virus) were completely removed using catalytic ozonation, whereas single ozonation was not able to eliminate JC virus even after 150 min of treatment. The higher performance of the catalytic process can be explained by the formation of hydroxyl radicals, proving that disinfection occurs in the liquid bulk and not due to adsorption at the volcanic rock.

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A Review of Removal of Pollutants from Water/Wastewater Using Different Types of Nanomaterials

Advances in Materials Science and Engineering ◽

10.1155/2014/825910 ◽

2014 ◽

Vol 2014 ◽

pp. 1-24 ◽

Cited By ~ 237

Author(s):

M. T. Amin ◽

A. A. Alazba ◽

U. Manzoor

Keyword(s):

Emerging Contaminants ◽

Cost Effective ◽

Water Industry ◽

Different Types ◽

Droughts And Floods ◽

Treatment Technologies ◽

Purification Unit ◽

Inorganic Solutes ◽

Increasing Demand ◽

Complex Organic

The rapidly increasing population, depleting water resources, and climate change resulting in prolonged droughts and floods have rendered drinking water a competitive resource in many parts of the world. The development of cost-effective and stable materials and methods for providing the fresh water in adequate amounts is the need of the water industry. Traditional water/wastewater treatment technologies remain ineffective for providing adequate safe water due to increasing demand of water coupled with stringent health guidelines and emerging contaminants. Nanotechnology-based multifunctional and highly efficient processes are providing affordable solutions to water/wastewater treatments that do not rely on large infrastructures or centralized systems. The aim of the present study is to review the possible applications of the nanoparticles/fibers for the removal of pollutants from water/wastewater. The paper will briefly overview the availability and practice of different nanomaterials (particles or fibers) for removal of viruses, inorganic solutes, heavy metals, metal ions, complex organic compounds, natural organic matter, nitrate, and other pollutants present in surface water, ground water, and/or industrial water. Finally, recommendations are made based on the current practices of nanotechnology applications in water industry for a stand-alone water purification unit for removing all types of contaminants from wastewater.

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Fate of COVID-19 Occurrences in Wastewater Systems: Emerging Detection and Treatment Technologies—A Review

Water ◽

10.3390/w12102680 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2680 ◽

Cited By ~ 1

Author(s):

Emmanuel Kweinor Tetteh ◽

Mark Opoku Amankwa ◽

Edward Kwaku Armah ◽

Sudesh Rathilal

Keyword(s):

Emerging Contaminants ◽

Advanced Oxidation Process ◽

Oxidation Process ◽

Wastewater Treatment Plants ◽

Sewage Treatment ◽

Membrane Bioreactors ◽

Magnetic Biosensor ◽

Wastewater Systems ◽

Treatment Technologies ◽

Water And Wastewater

The coronavirus (COVID-19) pandemic is currently posing a significant threat to the world’s public health and social-economic growth. Despite the rigorous international lockdown and quarantine efforts, the rate of COVID-19 infectious cases remains exceptionally high. Notwithstanding, the end route of COVID-19, together with emerging contaminants’ (antibiotics, pharmaceuticals, nanoplastics, pesticide, etc.) occurrence in wastewater treatment plants (WWTPs), poses a great challenge in wastewater settings. Therefore, this paper seeks to review an inter-disciplinary and technological approach as a roadmap for the water and wastewater settings to help fight COVID-19 and future waves of pandemics. This study explored wastewater–based epidemiology (WBE) potential for detecting SARS-CoV-2 and its metabolites in wastewater settings. Furthermore, the prospects of integrating innovative and robust technologies such as magnetic nanotechnology, advanced oxidation process, biosensors, and membrane bioreactors into the WWTPs to augment the risk of COVID-19’s environmental impacts and improve water quality are discussed. In terms of the diagnostics of COVID-19, potential biosensors such as sample–answer chip-, paper- and nanomaterials-based biosensors are highlighted. In conclusion, sewage treatment systems, together with magnetic biosensor diagnostics and WBE, could be a possible way to keep a surveillance on the outbreak of COVID-19 in communities around the globe, thereby identifying hotspots and curbing the diagnostic costs of testing. Photocatalysis prospects are high to inactivate coronavirus, and therefore a focus on safe nanotechnology and bioengineering should be encouraged.

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How ‘Green’ Are Aquaculture, Constructed Wetlands and Conventional Wastewater Treatment Systems?

Water Science & Technology ◽

10.2166/wst.1999.0133 ◽

1999 ◽

Vol 40 (3) ◽

pp. 45-50 ◽

Cited By ~ 24

Author(s):

Hans Brix

Keyword(s):

Water Quality ◽

Wastewater Treatment ◽

Constructed Wetlands ◽

Plant Biomass ◽

Renewable Energy Sources ◽

Energy Requirements ◽

Life Cycle Approach ◽

Treatment Technologies ◽

Recycling Potential ◽

Conventional Wastewater Treatment

The term ‘green’ is nowadays widely used (and misused) in connection with many types of technologies. If a technology is ‘green’ it usually means that the technology requires less non-renewable energy sources than other alternatives. However, other parameters need to be considered as well, such as sustainability, recycling potential, treatment capacity and potential, conservation of ecosystems, etc. In this paper the energy requirements and nutrient recycling potential of constructed wetlands and wastewater aquaculture facilities are compared with that of conventional wastewater treatment technologies. The energy requirements of constructed wetlands are very low, but if significant reuse of nutrients is included (aquaculture), the energy requirements increase significantly and usually beyond the energy equivalent of the biomass produced. This is especially true in cold temperate climates where the aquaculture systems need to be housed in heated greenhouses and artificial light must be provided to secure operation throughout the year. In countries where fresh water itself is a limiting resource and where the economic capability may limit the use of artificial fertilisers, the reuse potential of wastewater may be more important. The potential for sustainable cropping of the plant biomass is excellent in tropical wetlands as the plants have a high productivity and a continuous growing season. In order to evaluate in more detail the ‘greenness’ of the different wastewater treatment technologies, the life-cycle approach might be applied. However, because constructed wetlands, besides the water quality improvement function, perform a multitude of other functions such as biodiversity, habitat, climatic, hydrological and public use functions, methodologies need to be developed to evaluate these functions and to weigh them in relation to the water quality issues.

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Mitigation of emerging contaminants by full-scale horizontal flow constructed wetlands fed with secondary treated wastewater

Ecological Engineering ◽

10.1016/j.ecoleng.2016.11.054 ◽

2017 ◽

Vol 99 ◽

pp. 222-227 ◽

Cited By ~ 32

Author(s):

Víctor Matamoros ◽

Yolanda Rodríguez ◽

Josep M. Bayona

Keyword(s):

Constructed Wetlands ◽

Emerging Contaminants ◽

Full Scale ◽

Horizontal Flow ◽

Treated Wastewater

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Remediation of Polluted River Water by Biological, Chemical, Ecological and Engineering Processes

Sustainability ◽

10.3390/su12177017 ◽

2020 ◽

Vol 12 (17) ◽

pp. 7017

Author(s):

Hossain Md Anawar ◽

Rezaul Chowdhury

Keyword(s):

Water Treatment ◽

River Water ◽

Constructed Wetlands ◽

Low Cost ◽

Ecological Engineering ◽

Water Diversion ◽

River Ecosystems ◽

Algae Removal ◽

Secondary Pollution ◽

Treatment Technologies

Selection of appropriate river water treatment methods is important for the restoration of river ecosystems. An in-depth review of different river water treatment technologies has been carried out in this study. Among the physical-engineering processes, aeration is an effective, sustainable and popular technique which increases microbial activity and degrades organic pollutants. Other engineering techniques (water diversion, mechanical algae removal, hydraulic structures and dredging) are effective as well, but they are cost intensive and detrimental to river ecosystems. Riverbank filtration is a natural, slow and self-sustainable process which does not pose any adverse effects. Chemical treatments are criticised for their short-term solution, high cost and potential for secondary pollution. Ecological engineering-based techniques are preferable due to their high economic, environmental and ecological benefits, their ease of maintenance and the fact that they are free from secondary pollution. Constructed wetlands, microbial dosing, ecological floating beds and biofilms technologies are the most widely applicable ecological techniques, although some variabilities are observed in their performances. Constructed wetlands perform well under low hydraulic and pollutant loads. Sequential constructed wetland floating bed systems can overcome this limitation. Ecological floating beds are highly recommended for their low cost, high effectiveness and optimum plant growth facilities.

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