Environmental Science, Waste Management and Disposal, Water Science and Technology, Analytical Chemistry
63
Scopus Publications
Scopus Publications
Posttreatment of Effluents From UASB Reactors Through Vertical Flow Wetlands Coupled With Coagulant-Free Double Filtration for Safe Water Reuse Milene Fernanda Bornat Machado, Cleber Pinto da Silva, Danilo Gabriel dos Santos Matos, Sandro Xavier de Campos Water Environment Research, 2026 Water reuse is increasingly adopted to address global water scarcity, particularly for nonpotable applications. This study evaluated a pilot‐scale treatment train consisting of a vertical flow constructed wetland (VFCW) followed by sequential double filtration (DF) consisting of a sand filter followed by activated carbon and clinoptilolite media as posttreatment of domestic wastewater previously treated in an upflow anaerobic sludge blanket (UASB) reactor. The system was operated under three hydraulic loading rates (200, 400, and 600 mm/day), corresponding to organic loading rates of 26.8 to 94.9 g COD/m 2 ·day. The VFCW provided effective polishing of organic matter, achieving COD and BOD removals of up to 78% and 87%, respectively, relative to the UASB effluent, while additional total suspended solids removal ranged from approximately 25% at low and intermediate loadings to about 11% at the highest loading rate. Total nitrogen removal remained moderate and variable (~30%–65%), reflecting the predominance of aerobic conditions and limited denitrification potential within the wetland. Phosphorus removal in the VFCW was variable, with low efficiencies under low and high loadings (~14%–18%) and evidence of phosphorus remobilization under intermediate loading conditions. Microbial attenuation in the VFCW resulted in Escherichia coli removals of 90%–96% at low to intermediate hydraulic loads, with reduced performance at the highest loading rate. In contrast, the downstream DF consistently provided additional E. coli removal exceeding 99%, yielding final effluent concentrations on the order of 10 2 CFU/100 mL and complying with international reuse guidelines. Overall, the integrated VFCW–DF configuration functioned as a robust multibarrier system, enhancing operational reliability and demonstrating the potential of combined nature‐based and low‐cost filtration processes for decentralized wastewater reuse. Importantly, the results demonstrate that coagulant‐free double filtration acts as a stabilizing barrier, transforming variable wetland performance into consistent and reuse‐compliant effluent quality.
Teaching Chemistry Proposal for Integrated Agricultural Technical Course on the Theme of Contamination by Pesticides and Heavy Metals in a Water Reservoir Milene Fernanda Bornat Machado, Elias Da Costa, Sandro Xavier de Campos Orbital, 2025 This paper presents a proposal for Teaching Chemistry (TC) with a focus on Environmental Education (EE) using the three pedagogical moments (3MP) as a didactic strategy and a local theme on the problem of environmental contamination of a water supply reservoir by pesticides and heavy metals. The research was carried out with vocational students from the Integrated Agricultural Technical Course at a public school in the city of Ponta Grossa, Paraná. The work used scientific articles, television reports, software for data collection and, at the end, the students were encouraged to produce an e-mail to send to the local authorities about the actions being taken to deal with the problem of contamination. The results point to the need for chemistry classes to effectively articulate local content and themes on environmental contamination, with a view to critically training agricultural technicians, which will enable them to reflect on their rights and duties as citizens. It was found that there was a significant improvement in the understanding of chemical concepts and criticality in relation to environmental problems. Thus, the use of the 3MP and an environmental theme would enable technicians to be trained as holders of scientific knowledge and professional skills in tune with the social and environmental reality.
Treatment of Synthetic Effluent Containing Azo Dyes by Coagulation and Rapid Filtration Danilo Matos, Francielli Casanova Monteiro, Pablo Elias Bochnie, Sandro Xavier de Campos Orbital, 2025 The present study evaluated the treatment of synthetic effluent containing azo dyes using a coagulation system followed by double filtration (DF) and triple filtration (TF). Treatment efficiency was assessed based on the removal of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Linear Alkyl Sulfate (LAS), Total Nitrogen (TN), nitrate, nitrite, turbidity, color, and the dyes Ponceau and Tartrazine. After coagulation and DF, removals reached 76.73% COD, 81.31% BOD, 42.31% LAS, 80.00% TN, 40.96% nitrate, 100.00% nitrite, 99.58% turbidity, and 92.86–100.00% color. Following TF, removals were greater than 77.00% for nitrate, above 98.00% for COD and BOD, and approximately 100.00% for LAS, TN, nitrite, turbidity, and color. Although chloride and conductivity removals were low, the values remained within the effluent disposal limits established by Brazilian legislation. For the dyes, the DF step achieved over 40.00% removal, while TF reduced dye concentrations below the quantification limits for both Ponceau and Tartrazine. The main removal mechanisms were adsorption via the porosity of activated carbon and ion exchange by zeolite. Overall, the combined coagulation, DF, and TF processes demonstrated high removal efficiencies for most evaluated parameters, indicating their suitability for treating effluents containing azo dyes.
Comparative study on the action of compost, biochar, and cellulase in the composting process of tobacco in a facultative reactor Rolan Roney Ressetti, Sandro Xavier de Campos Engenharia Sanitaria E Ambiental, 2025 In this work, a comparative study was carried out on the influence of three additives (compost, biochar, and cellulase) on tobacco composting, with solid organic waste and sawdust, in a facultative reactor. Four reactors were constructed. In one of the reactors, only the substrate was added, while in the others, the additives were added, one in each reactor, according to the proportions recommended in the literature. In the reactors with additives, the temperatures reached peaks of up to 60°C, remaining around 50°C during the thermophilic phase, which was sufficient to achieve compost stability. After 110 days, the seed germination rate exceeded 95%. The data obtained through spectroscopic analyses (UV/Vis, FTIR, and 13C NMR) indicated that the simplest molecules were degraded, and the humification and condensed aromatic cluster indices increased. The data obtained demonstrated the efficiency of the additives, since all of them presented better results than the reference reactor. Biochar was the additive that demonstrated the greatest efficiency, followed by cellulase (in second place) and compost (in third).
Post-Treatment of Microbrewery Effluent Through Coagulation and Rapid Filtration Amanda Vedam Pupin, Cleber Pinto Da Silva, Sandro Xavier De Campos Orbital, 2025 This study evaluated the efficiency of double and triple filtration technology associated with coagulation as a post-treatment of microbrewery effluent from an anaerobic decant-digester (ADD). The coagulants used were ferric chloride (FeCl₃), polyaluminum chloride (PAC), and a tannin-based natural coagulant (TAN). The filtration rate used was 120 m³/m²/day. The efficiency of the system was evaluated through physicochemical parameters. The post-treatment, which combined coagulation and triple filtration, achieved removals of 98% for apparent color, 64% for Chemical Oxygen Demand (COD), 59% for Biochemical Oxygen Demand (BOD), 100% for Phenols, 99% for Total Phosphorus (TP), 77% for Total Kjeldahl Nitrogen (TKN), 96% for Total Suspended Solids (TSS) and 99% for Turbidity, with results varying according to the coagulant used. Results indicated that PAC was the most efficient coagulant at lower concentrations, followed by TAN and FeCl₃. The post-treatment system proved to be highly effective in contaminant removal, offering a promising solution for the treatment of microbrewery effluents.
The Use of Constructed Wetlands to Treat Effluents for Water Reuse Sandro Xavier de Campos, Manuel Soto Environments Mdpi, 2024 Constructed wetland systems (CWs) are technologies based on natural processes for pollutant removal and have been more and more accepted in the treatment of domestic and industrial wastewater. This study selected and reviewed articles published in the last six years involving the use of different CW conceptions and their association with other technologies to treat different effluents and evaluated the quality of the effluents for reuse. From a total of 81 articles reviewed, 41 presented quantitative data on the quality of the treated effluent in relation to the requirements of the reuse regulations in different countries of the world. CWs can be used to treat gray water and runoff water, as well as domestic and industrial effluents with the purpose of reusing them. While studies on the removal of new chemical and biological substances have increased, challenges are associated with the optimization of CWs to improve the removal of pathogens and new contaminants that have appeared more recently. The potential for the improved removal of those pollutants lies in the association of CWs with conventional and advanced technologies in new configurations. We concluded that studies related to the reuse of effluents using CWs are in constant evolution, with experiments at different scales. The perspectives are promising since CWs are an economic, environmentally friendly, and efficient technology to help in the mitigation of water scarcity problems imposed by climate changes.
