Water treatment plants treat raw water making it suitable for consumption. Treatment stages are linked to the quality status of the treatment. The classes of antibiotic resistance genes as impacted by treatment stages remain under explored.
View Article and Find Full Text PDFDifferent stages of drinking water treatment plants (DWTPs) play specific roles in diverse contaminants' removal present in natural water sources. Although the stages are recorded to promote adequate treatment of water, the occurrence of pathogenic bacteria (PB) and antibiotic-resistant bacteria (ARB) in the treated water and the changes in their diversity and abundance as it passed down to the end users through the drinking water distribution systems (DWDSs), is a great concern, especially to human health. This could imply that the different stages and the distribution system provide a good microenvironment for their growth.
View Article and Find Full Text PDFWastewater treatment is notorious for its hefty carbon footprint, accounting for 1-2% of global greenhouse gas (GHG) emissions. Nonetheless, the treatment process itself could also present an innovative carbon dioxide removal (CDR) approach. Here, the calcium (Ca)-rich effluent of a phosphorus (P) recovery system from municipal wastewater (P recovered as calcium phosphate) was used for CDR.
View Article and Find Full Text PDFAn insightful attempt has been made in this review and the primary objective was to meticulously provide an update on the sustainabilities, advances and challenges pertaining the removal of ammonia from water and wastewater. Specifically, ammonia is a versatile compound that prevails in various spheres of the environment, and if not properly managed, this chemical species could pose severe ecological pressure and toxicity to different receiving environments and its biota. The notorious footprints of ammonia could be traced to anoxic conditions, an infestation of aquatic ecosystems, hyperactivity, convulsion, and methaemoglobin, popularly known as the "blue baby syndrome".
View Article and Find Full Text PDFThe ever-growing contamination of surface water due to various catchment activities poses threats and stress to downstream water treatment entities. Specifically, the presence of ammonia, microbial contaminants, organic matter, and heavy metals has been an issue of paramount concern to water treatment entities since stringent regulatory frameworks require these pollutants to be removed prior to water consumption. Herein, a hybrid approach that integrates struvite crystallization (precipitation) and breakpoint chlorination (stripping) for the removal of ammonia from aqueous solution was evaluated.
View Article and Find Full Text PDFIndustrial processes typically produce large wastewater volumes, which, if left untreated, greatly affect receiving ecosystems. However, wastewater treatment can be costly and energy-intensive, with the developing world particularly struggling with wastewater management. As such, simple and cost-effective solutions are urgently required with the passive (no energy or reagents) co-treatment of different wastewater matrices holding great promise.
View Article and Find Full Text PDFThe permeable reactive barrier has been deemed as the most prudent and pragmatic way to passively manage and remediate acid mine drainage (AMD). Herein, insights into mechanisms governing the removal of inorganic contaminants from AMD using a permeable reactive barrier (PRB), i.e.
View Article and Find Full Text PDFNanomaterials (Basel)
February 2022
This study presents the first known exploration of Congo red dye (CR) adsorption by a polycationic Fe/Al Di-metal nanostructured composite (PDFe/Al) synthesised using Fe(III) and Al(III) recovered from authentic acid mine drainage (AMD). The PDFe/Al successfully removed CR from the aqueous solution. The mineralogical, microstructural, and chemical properties of the synthesised PDFe/Al adsorbent (before and after adsorption) were studied using state-of-the-art analytical instruments.
View Article and Find Full Text PDFIn this novel study, acid mine drainage (AMD) was treated using a hybrid approach comprising a nano-and-biotic system synergistically integrated in a step-wise and modular fashion. Specifically, the treatment chains were made up of different stages, which comprise, neutralization using activated magnesite or MgO-nanoparticles (NPs) (Stage 1) and polishing the product water using a series of wetlands (Stage 2) in a step-wise connection. In stage One (1), real AMD was treated with MgO-NPs at a ratio of 1:100 (1 g/100 mL - w/v ratio), 500 rpm of mixing speed, and One (1) hour of hydraulic retention time (HRT) whilst in stage 2, the final water was fed into constructed wetlands, i.
View Article and Find Full Text PDFThe valorisation of wastewaters for minerals recovery and their potential beneficiation has gained enormous attention recently. In this study the removal of phosphate and ammonia from municipal wastewater using activated magnesite resulted in the formation of struvite. The optimum conditions for the synthesis of struvite were 60 min of mixing, 300 rpm mixing speed, 1 g of activated magnesite and room temperature, whilst optimum conditions for the treatment of acid mine drainage (AMD) using the synthesized struvite were 45 min of mixing, 20 g of struvite dosage, 1000 mL, and 300 rpm mixing speed.
View Article and Find Full Text PDFThe co-management of different wastewater matrices can lead to synergistic effects in terms of pollutants removal. Here, the co-treatment of real municipal wastewater (MWW) and acid mine drainage (AMD) is comprehensively examined. Under the identified optimum co-treatment condition, i.
View Article and Find Full Text PDFThis study explored an eco-friendly approach for the synthesis of novel aluminium enriched ferric oxide-hydroxide (Fe/AlO(OH)) from authentic acid mine drainage (AMD). The synthesized Fe/AlO(OH) was subsequently tested for arsenate removal capabilities. Fe/AlO(OH) was synthesized from bona fide AMD via selective precipitation, thermal activation, and vibratory ball milling.
View Article and Find Full Text PDFThe present paper aims at determining the status of surface water quality by applying the treatability index for the raw water in four water treatment plants (WTPs), namely Vaalkop, Klipdrift, Wallmansthal, and Cullinan. These plants are based in South Africa. Sampling was conducted from July 2011 to June 2018 (7 years).
View Article and Find Full Text PDFIn this study, we developed an innovative spherical biochar with high porosity and excellent paracetamol (PRC) adsorption capacity. The optimal pyrolysis temperatures for the preparation of spherical biochar (derived from pure glucose) and non-spherical biochar (from pomelo peel wastes) were obtained at 900 °C and 700 °C, respectively. Various advanced techniques were applied to characterize the prepared biochars.
View Article and Find Full Text PDFThe ability of calcined magnesite for Methylene Blue (MB), Direct Red 81 (DR81), Methyl Orange (MO) and Crystal Violet (CV) dye removal was evaluated in this study. The experiments were designed to test the hypothesis that alkaline earth carbonates can remove dyes from water through a combination of sorption and coagulative reactions involving Mg. To achieve that, several operational factors like residence time, dosage, adsorbent concentration and temperature were appraised.
View Article and Find Full Text PDFThe environmental sustainability of acid mine drainage (AMD) treatment at semi-industrial scale is examined by means of the life cycle assessment (LCA) methodology. An integrated process which includes magnesite, lime, soda ash and CO bubbling treatment was employed to effectively treat, at semi-industrial scale, AMD originating from a coal mine in South Africa. Economic aspects are also discussed.
View Article and Find Full Text PDFDyes are growing to be a problematic class of pollutants to the environment. The disposal of dyes in water resources has bad aesthetic and health effects, hence the need to remove them from the environment. The need for treatment methods that are effective and low in price is rising hence a lot of research interest is being diverted towards adsorbents that are cheap, preferable naturally occurring materials like clays.
View Article and Find Full Text PDFIn the present study, nanocomposite of cryptocrystalline magnesite-bentonite clay was used as a novel technology for removal of phosphates from municipal effluents. Vibratory ball miller was used for fabrication of the composite. Removal of phosphate from an aqueous solution was achieved using batch experimental procedures.
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