Discharge Standards Research Articles

Sverdlovsk esports student league - reserve of the Sverdlovsk region national team

Relevance. The first official competitions of the Sverdlovsk region in computer sports were the 2019 Sverdlovsk Region Cup in computer sports. Teams consisting of 5 people were allowed to participate in competitions in the Combat Arena discipline, in the form of the DOTA2 program. 8 teams took part in the competition, and 3 teams in full were the teams of Yekaterinburg universities. This is a very important point, since without the participation of university teams, athletes of the Sverdlovsk region would not be able to meet the discharge standards, since in accordance with the requirements of the Unified All-Russian Sports Classification (hereinafter EVSK) for the sport of computer sports, at least 6 teams are required to perform discharge standards.The purpose of the study was to quantify such a trend of mass sports as student computer sports. Methods and organization of the study: as a result of the analysis of data on the composition of the teams participating in the Sverdlovsk Region Cup (hereinafter CSR) in computer sports in 2019-2023 according to the combat arena discipline, in the form of the DOTA2 program and the identification among them of the national teams of educational institutions participating in the Sverdlovsk esports Student League, as well as the data are compared with the number of participating teams SCSL in the specified program type.The results of the study and their discussion. Low motivation of athletes remains among the main problems in student computer sports, as well as high-achievement computer sports. Not all gamers are esports players. By participating in competitions, they try to become them, but the goal of a gamer is to enjoy video games. And the main motivation of a gamer when entering computer sports is the desire to earn income in the form of cash prizes.Conclusions. To increase motivation, the following solutions are possible: Divide the WKSL into two parallel tournaments for university and university students. To supplement the current EVSC in computer sports with the possibility of fulfilling the discharge standards for the winners of regional physical education events.

Green nanoparticles blending with polyacrylonitrile ultrafiltration membrane for antifouling oily wastewater treatment

This work prepares novel polyacrylonitrile (PAN) membranes by incorporating eggplant waste (EGW) as eco-friendly green nanoparticles (NPs) with PAN membranes to enhance the antifouling of PAN membranes to separate oil from oily wastewater (OWW). The modified PAN membranes are characterized by Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE-SEM), and measurements of the contact angle, porosity, and mechanical properties. The effect of EGW NPs content on membrane properties and morphology, its entire performance, and its antifouling characteristics is investigated. The performance of the PAN-EGW membranes is evaluated by pure water flux and oil rejection. The PAN membrane incorporated with 0.1 wt% EGW NPs enhances a pure water flux to 204.71 L/m2 h, exceeding that of the pristine PAN membrane (136.51 L/m2 h). This can be attributed to the low contact angle (39.66◦), high surface membrane porosity (91%), and good tensile strength (8.2 MPa) for PAN-EGW membranes compared to the contact angle (68.56◦), surface membrane porosity (69%), and tensile strength (5.1 MPa) for the pristine PAN membrane. Another significant improvement noticed is the excellent oil rejection by the modified membranes (about 99.95%, 95.50%, and 90.00% at oil concentrations of 1000, 100, and 10 ppm, respectively, and a transmembrane pressure (TMP) of 2 bar); treated-wastewater oil content that complies with the World Health Organization (WHO) environmental discharge standards (< 5 ppm) is achieved. Also, the antifouling performance is improved; a higher flux recovery ratio (FRR) is obtained (about 94.43%). In addition, the oil separation efficiency remains stable with a minor decrease in permeate flux after four cycles. This study demonstrates that the novel PAN-EGW membranes have great promise and potential for purifying OWW, particularly at low oil concentrations (10 ppm) compared to pristine PAN membranes, attributable to their high separation efficiency, oil-fouling resistance, and excellent environmental durability.

Assigning strategic COD flow to enhance denitrification coupled with anaerobic digestion and anammox for systematic upgradation of advanced nitrogen removal from food waste digestate

Anammox is a low-carbon and efficient technology for treating high-strength ammonium in food waste digestate (FWD). However, achieving superior low-nitrogen effluent levels to meet strict discharge standards remains challenging. This study proposes an anammox-based process that integrates simultaneous denitrification and methanogenesis (SDM), partial nitrification (PN), and simultaneous anammox and denitrification (SAD) to realize advanced nitrogen removal from FWD by strategically utilizing influent organic matter. The SAD process achieved an inorganic nitrogen removal efficiency of 94.0 %, with the anammox reaction contributing 96.0 %. Residual nitrate in the SAD effluent was recirculated into SDM, maintaining a removal efficiency of 95 %–97 %. Profiling wastewater and material flows in the integrated process showed a 97.2 % nitrogen removal efficiency, with effluent nitrogen levels meeting discharge standards (<70 mg/L for municipal sewer systems). 3D-fluorescence analysis indicated that quasi-humic acid was effectively removed through SDM. Soluble microbial by-products of FWD served as carbon source for the denitrifying bacteria in SAD. Controlling influent bypass flow and effluent recirculation allowed for strategic allocation of chemical oxygen demand (COD) flow, achieving a total removal efficiency of 71.8 %. SDM removed 45.8 % COD, followed by PN at 13.4 % and SAD at 12.6 %. Compared with those of conventional nitrification and denitrification process, the economic cost, greenhouse gas emission, and total environmental impact of this integrated process were reduced by 85.8 %, 35.8 %, and 84.1 %, respectively. This study provides new insights into the application of anammox-based process for attaining advanced nitrogen removal while minimizing environmental impact.

Tertiary treatment of dairy wastewater applying a microalga-fungus consortium

ABSTRACT This paper aimed to apply filamentous fungi (Penicillium oxalicum and Cunninghamella echinulata), the microalga Tetradesmus obliquus and their co-culture in advanced treatment (tertiary treatment) of cheese whey. The bioremediation process was carried out in agitated flasks and bubble column bioreactors with different concentrations of chemical oxygen demand (COD) (223–1663 mg L − 1), total nitrogen (TN) (13–61 mg L − 1), and total phosphorus (TP) (3–26 mg L − 1). The results obtained in shaken flasks showed a superiority of the consortium compared to the systems with separated species. In this sense, the treatment was carried out in a bubble column reactor, and the consortium formed by the microalga and the fungus C. echinulata showed a greater efficiency (at a light intensity of 100 µmol m − 2 s − 1), promoting by the symbiosis to reach removal efficiencies of up to 93.7, 78.8 and 93.4% for COD, TN and TP, respectively; meeting Brazilian and European standards for discharge into water bodies. In addition, no pH adjustment was required during the co-culture treatment, demonstrating the buffering effect of using these two types of microorganisms. Therefore, the use of the consortium formed by T. obliquus and C. echinulata as a remediator was highly promising to promote the advanced treatment of cheese whey.

Carbon performance analysis of upgraded wastewater treatment plants in key control areas of the Ziya River Basin in China

Wastewater treatment plants (WWTPs) are one of the largest sources of greenhouse gas (GHG) emissions, and they are also one of the largest energy consumption industries in urban systems. With the progression of upgrading and standard-rising, WWTPs both directly and indirectly increase carbon emissions from the increased investments in facilities and usages in electricity as well as chemical agents. Here, we collected operational data from 15 WWTPs in the key control areas of the Ziya River Basin in North China and accounted for the changes in carbon performance at different technical upgrade methods. Results showed that the average carbon emission performance increased by 0.487 kg CO2/m3 after the upgrade. Carbon emissions from electricity consumption, chemical usage, biochemical process and sludge treatment accounted for 42%, 17%, 24%, and 17% of the total improvement in carbon emission performance, respectively. Reducing energy consumption, regulating chemical use and sludge comprehensive utilization are the key to carbon emission reduction. It further proposes that the development of wastewater treatment discharge standards should fully consider the comprehensive utilization of water quality classification. Regions with favorable natural conditions should make full use of their advantages by adopting economically feasible, low-energy-consuming technologies such as constructed wetlands, which offer carbon sequestration and landscaping benefits. This study provides guidance on the selection of technological pathways for pollution reduction and carbon mitigation in the wastewater treatment industry and on achieving sustainable water resource utilization.

Physicochemical characterization of wastewater from the Niamey National Hospital (NNH) (Niger) and assessment of its impact on the environment

The Niamey National Hospital (NNH) is among the reference hospital in the Niamey region (Niger) to after the quality of care it offers to the population. However, these activities have a negative impact on the quality of the water of the river constituting one of the main sources of water supply for the population of Niamey and gardening activities. This study aims to determine the physicochemical quality of wastewater from the NNH activated sludge treatment plant and its impact on the environment. To carry out this study, twenty (20) wastewater samples were taken at the outlet of the NNH treatment station. The sampling lasted five (5) weeks to take into count fluctuations. The results obtained indicate that the average values of physicochemical parameters such as: the pH (6,91), temperature (27.825°C), conductivity (574.80 µS/cm) and certain heavy metals of this hospital are compliance with national and international standards for wastewater discharge. However, it was noted that the average values ​​obtained at the HNN for copper (1.982 mg/L); zinc (1.077 mg/L); in phosphorus (18.065 mg/L); DCO (808 mgO2/L) and DBO5 (442.5 mgO2/L) do not comply with national and international wastewater discharge standards. These abnormal levels must be treated before being released into the river.

Recycling of sludge residue as a coagulant for phosphorus removal from aqueous solutions.

Phosphorus pollution poses a significant challenge in addressing water contamination. The coagulant is one of the effective methods to remove phosphorus from wastewater. Abundant Al and Fe oxides in sludge residue make it have great potential to synthesize water treatment coagulants. However, the utilization of sludge residue for preparation of coagulant was seldom investigated. In this study, we fabricated a novel coagulant, polyaluminum ferric chloride (SM-PAC), using sludge residue as a raw material through acid leaching and polymerization processes. Characterization results confirm that the parameters of SM-PAC meet the specifications outlined in the national standard (GB/T 22627-2022). We investigated the effects of pH, dosage, initial phosphorus concentration, and contact time on the removal efficiency of SM-PAC. As anticipated, the prepared SM-PAC exhibited a significant efficacy in removing phosphorus, meeting the discharge standards set for municipal sewage. Furthermore, the adsorption kinetics analysis suggests that the predominant mode of phosphorus adsorption on SM-PAC is chemical adsorption. Furthermore, the SM-PAC was employed in the actual wastewater treatment plant and exhibited excellent efficiency in phosphorus removal. The utilization of SM-PAC can not only effectively address the issue of sludge disposal but also achieve the goal of "treating waste with waste." It is expected that the proposed method of reusing sludge residue as a resource can provide a sustainable way to synthesize a coagulant for phosphorus removal.

The urgent need to reduce phosphorus discharges for sustainable mangrove wetland management

Phosphorus affects microbial metabolic activity, nitrogen and carbon cycling in mangrove sediment, but its influence on carbon stability and greenhouse gases emission remains unclear. This study compared greenhouse gases (CO2, N2O, and CH4) emissions from mangrove sediment receiving wastewater containing various phosphorus concentrations, and evaluated its long term effect on sediment carbon flux when phosphorus pollution is eliminated. Significant increases in greenhouse gases flux and decrease of total organic carbon and readily oxidizable organic carbon in the sediment were observed after phosphorus discharge. Specifically, the N2O flux was reduced significantly at high phosphorus levels while the CO2 flux and the microbial biomass organic carbon was increased. The copy numbers of ammonia oxidation (AOA-amoA, AOB-amoA) gene, denitrification (narG, nirK) gene and methanogenesis (mcrA) gene increased with the increasing phosphorus concentration. During the wastewater discharge period for 70 days, the global warming potential of sediment flux at high phosphorus discharge condition was more than 4 times that of the control group, and the loss of total organic carbon and readily oxidizable organic carbon was 4.66 % and 7.1 %, respectively. During the remediation period (71–101 days), the greenhouse gases flux decreased rapidly, ends up with a similar level of the control group. Our results indicate that using mangrove wetland for pollution minimization in the coastal aquaculture industry could increase greenhouse gases emisison significantly, it is therefore essential to reduce phosphorus discharges from various anthropogenic activities, and local authorities must set up more stringent discharge standards in the future.

Analyzing greenhouse gas emissions and influencing factors of 247 actual wastewater treatment plants in China using emission factor and operational data integrated methods (ODIM).

In response to China's policies on pollution control and carbon emission (CE) reductions, more stringent regulations have been implemented to evaluate CE in wastewater treatment facilities. In this study, we have analyzed CE from China's wastewater treatment plants (WWTPs) and influencing factor. Emission factor (EF) and operational data integrated methods (ODIM) were utilized to measure emissions, using data collected from 247 WWTPs over a 1-year period across seven regions in China. The average CE intensity was 0.45 kgCO2-eq/m3, affected by region, season, influent water quality, treatment processes, effluent discharge standards, and facilities. The scale effect was obvious only in the range of 2 × 105 m3/day. Underground WWTPs exhibited significantly higher CE compared to aboveground WWTPs. In summary, the assessment of CE in 247 actual WWTPs not only identifies emission reduction potential but also provides a scientific basis for formulating targeted emission reduction measures.

Post-treatment of high-rate activated sludge effluent via zeolite adsorption and recovery of ammonium-nitrogen as alternative fertilising products

This study investigates the potential to connect nutrient flows between wastewater treatment and agriculture through a two-stage nitrogen (N) recovery system composed of high-rate activated sludge treatment in contact stabilisation mode (HRAS/CS) and column adsorption with zeolite. The HRAS/CS process removes organic matter and suspended solids in wastewater, leaving N behind in the effluent. The N was successfully recovered with the zeolite column under different scenarios, generating N and K-rich by-products. The regeneration effluent from the zeolite column with KCl contained 60–845 mg NH4+-N/L and 1.6–14.3 g K/L, having potential for use as fertigation water. The N-saturated zeolite contained 1.5–8.4 mg N/g and 14.3–19.3 mg K/g of the product fresh weight and low contaminant content, making it potentially eligible as various fertilising products. Adsorption can thus concentrate N from HRAS/CS effluent and produce by-products with potential agricultural value while meeting chemical oxygen demand and total nitrogen discharge standards.

Effluent quality and reuse potential of wastewater treated in constructed wetlands in Southern Brazil

ABSTRACT The main objective of this study was to evaluate the quality and reuse potential of treated effluents by constructed wetlands (CW) systems utilized for decentralized wastewater treatment in urban and rural scenarios in southern Brazil. The assessment, based on Brazilian discharge standards and wastewater reuse guidelines, revealed a close link between treatment efficiency and technological configurations, considering diverse inlet wastewater sources. Most CW treated effluents complied with regulatory standards for disposal, prompting the exploration of reuse scenarios in urban and agricultural settings. However, the study underscores the imperative for rigorous disinfection due to the limited microbiological removal capacity of CW. Overall, the research emphasizes the adaptability and resilience of CW in treating diverse wastewater compositions, highlighting their pivotal role in advancing circular economy principles within sanitation services. Importantly, the findings suggest significant potential for treated wastewater reuse in both urban and agricultural settings. Urban applications, including toilet flushing, floor washing, and garden irrigation, prove feasible for CW systems situated in residential and commercial buildings. Meanwhile, rural CW systems demonstrate suitability for reclaimed water directed toward crop fertigation, tailored to the specific needs and irrigation methods of various crops.

Replenishment of landscape water with reclaimed water: threshold of hydraulic retention time employing transparency as a control indicator

ABSTRACT There exists a significant risk of water blooms during the utilization of recycled water in landscape environments. The nitrogen and phosphorus discharge standards of sewage treatment plants are very low. Controlling hydraulic retention time (HRT) is currently the most effective means to control water bloom. This article proposes a new method for determining the HRT threshold based on water transparency as a control indicator. The following results were obtained: (1) with the nitrogen and phosphorus concentrations of 15 and 0.5 mg/L, respectively, the threshold for HRT under high temperature and strong light is 4.6 days, while the threshold under low temperature and low light is 11.5 days. (2) With the nitrogen and phosphorus concentrations of 10 and 0.3 mg/L, respectively, the threshold for HRT under high temperature and strong light is 5 days, while the threshold under low temperature and low light conditions is 12.3 days. (3) The HRT threshold obtained under high temperature and strong light is lower than that obtained under low temperature and low light conditions. (4) The higher the concentrations of nitrogen and phosphorus, the smaller the HRT threshold obtained. (5) Blue algae have stronger adaptability than green algae and diatoms.

Fabrication and characterization of a novel multilayer heterojunction Si3N4-PbO2 nanocomposite electrode and its application on electrocatalysis degradation of sulfathiazole

To lengthen the lifetime and extend the potential commercial applications of lead dioxide electrode, herein, a novel multilayer heterojunction Ti/ SnO2-Sb2O3/ graphene oxide/ carbon nanotube/ Si3N4-PbO2 electrode (Si3N4-PbO2 electrode) was fabricated by co-electrodeposition process that doping Si3N4 nanoparticles in eletroplating solution. Various spectroscopic and microscopic techniques, including scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), were employed to characterize the surface of the fabricated electrode. The EDS analysis confirmed the successful attachment of 5.49 %wt Si and 2.46 %wt N elements from Si3N4 nanoparticles onto the PbO2 surface, while the XRD results indicated a shift in the preferred orientation of PbO2 grains from β(110) to β(101). The water adsorption energy and ·OH desorption energy in the electrocatalysis process were determined to be 0.71 eV and 0.241 eV through theoretical calculating. Subsequently, the Si3N4-PbO2 electrode was employed as an anode for the electrocatalytic degradation of sulfathiazole-simulated wastewater and real sulfonamides wastewater. Under optimized conditions determined via response surface methodology (RSM), the COD degradation efficiency reached 69.37 % for sulfathiazole and 62.35 % for real sulfonamides wastewater. The final COD concentration of the real sulfonamides wastewater was reduced to 77.05 mg/L, under the national urban sewage discharge standard. Finally, the degradation mechanism and pathway of sulfathiazole has been arranged based on the electron spin resonance (ESR), cyclic voltammetry (CV), while the intermediates were detected by Gas Chromatography-Mass Spectrometer (GC-MS) and the reactive sites of sulfathiazole were predicted by using Fukui function.

Toxic heavy metals in a landfill environment (Vientiane, Laos): Fish species and associated health risk assessment

Leachates from municipal landfills introduce toxic heavy metals into water, causing bioaccumulation. This study assesses metal levels and potential human health risks associated with consuming Anabas testudineus and Channa striata. Inductively coupled plasma mass spectrometry detected Cd, Cu, Cr, Ni, Pb, and Zn in both fish species. Leachate metal concentrations meet international discharge standards, Cd, Cr, and Pb in the fish exceed the international accepted values. Gastrointestinal tract+liver samples show significant variation between species, particularly in Cd and Pb. EDI, THQ/HI, and TR for the both species fall below TDIs, lower than the limit of 1, and within the acceptable range of the US-EPA permissible limit, respectively. Fish consumption appears safe regarding carcinogenic risk, but exceeding metal limits could impact heavy metals accumulation in the local food chain. Raising public awareness is crucial, and governmental agencies and environmental organizations should enhance waste treatment technologies and enact relevant health legislation.

Assessment of Liberia's Beer Industry Effluent Discharge Parameters in the Context of Urban Sustainability

Due to untreated brewery effluent and increasing industrial growth, most of Liberia's rivers have considerable water body pollution. The nature and extent of pollution caused by wastewater effluent discharged into these environments have not been thoroughly examined. This study looked into the effects of such effluents on the beer industry in Montserrado, Liberia. It assesses discharged effluent parameters, sustainable management practices, and potential wastewater reuse options within the context of urban sustainability. The findings highlight the need for immediate and substantial intervention to mitigate escalating pollution and associated health risks. The research also noted for the development of practical national industrial discharge standards, regulatory and management framework, tailored to local contexts, rather than a uniform application of stringent regulations that may hinder sectoral growth and intensify public health issues in under-resourced areas. Furthermore, the effectiveness of some treatment technologies. Technology consideration such as onsite treatment and irrigation that enable water reuse options (cooling, agriculture, and resource recovery) which can significantly reduce the environmental footprint of breweries were recommended. However, the implementation of these technologies may face challenges due to infrastructure deficiencies, financial constraints, and public perception regarding the safety and quality of reused wastewater. The analysis concludes that enhancing wastewater discharge effluents management is key for promoting sustainable industrial growth, improving water conservation, and gaining public trust and acceptance. Achieving these goals requires a concerted effort to strengthen policy, enhance technical capacity, and invest in community engagement to foster a sustainable and economically viable brewery sector.

WASTEWATER TREATMENT OF COAL TAR PROCESSING PROCESS FROM PHENOL

The coal tar processing process provides the chemical industry with valuable products: naphthalene, cresol, xylenols, phenol, technical oils and lubricants. The most significant product of coal tar processing is anthracene, which is a raw material for the production of carbon black. The prospects for the implementation of the coal tar processing process entail a danger to the environment and public health.Wastewater formed during the processing process has a complex chemical composition, mainly represented by organic aromatic compounds. Wastewater pollutants significantly exceed discharge standards permissible for discharge into the Centralized Wastewater Disposal System of Settlements and Urban Districts. Phenol, which has the third hazard class according to the standards of maximum permissible concentrations of harmful substances in the waters of water bodies of fishery importance, is particularly dangerous. The toxic effect of phenol leads to the suppression of biocenoses, a decrease in the number of living organisms, negatively affects human health, and can lead to death. Based on the above, in order to reduce the anthropogenic load on the environment and maintain the quality of water resources, it is necessary to carry out a set of environmental measures aimed at wastewater treatment.The article presents methods of wastewater purification from phenol, describes complex purification methods and formulates proposals for the technology of wastewater treatment of the enterprise. Spectral and quantitative chemical analysis were performed to determine the composition of wastewater. Regenerative cleaning methods are proposed. Methods for wastewater treatment have been formulated and implemented. Methods for wastewater treatment of the coal tar processing process are proposed.The aims of research are to reduce the concentration of phenol in wastewater to the standard values permissible for discharge into the Centralized Wastewater Disposal System of Settlements and Urban Districts, based on experimental data; formulate a proposal for the wastewater treatment of the coal tar processing process from phenol.Objectives of the work are to study the composition of the source wastewater; to consider methods of wastewater treatment from phenols; to carry out wastewater treatment, based on the results of the study, to propose a wastewater treatment scheme.The object of the study is the wastewater of the enterprise after the coal tar processing process.

Non-targeted analysis and toxicity prediction for evaluation of photocatalytic membrane distillation removing organic contaminants from hypersaline oil and gas field-produced water

Membrane distillation (MD) has received ample recognition for treating complex wastewater, including hypersaline oil and gas (O&G) produced water (PW). Rigorous water quality assessment is critical in evaluating PW treatment because PW consists of numerous contaminants beyond the targets listed in general discharge and reuse standards. This study evaluated a novel photocatalytic membrane distillation (PMD) process, with and without a UV light source, against a standard vacuum membrane distillation (VMD) process for treating PW, utilizing targeted analyses and a non-targeted chemical identification workflow coupled with toxicity predictions. PMD with UV light resulted in better removals of dissolved organic carbon, ammoniacal nitrogen, and conductivity. Targeted organic analyses identified only trace amounts of acetone and 2-butanone in distillates. According to non-targeted analysis, the number of suspects reduced from 65 in feed to 25–30 across all distillate samples. Certain physicochemical properties of compounds influenced contaminant rejection in different MD configurations. According to preliminary toxicity predictions, VMD, PMD with and without UV distillate samples, respectively contained 21, 22, and 23 suspects associated with critical toxicity concerns. Overall, non-targeted analysis together with toxicity prediction provides a competent supportive tool to assess treatment efficiency and potential impacts on public health and the environment during PW reuse.

Occurrence of micropollutants in rural domestic wastewater in Zhejiang Province, China and corresponding wastewater-based epidemiology analysis

By 2021, rural regions in China were occupied by over 500 million residents, generating an annual volume of 19.5 billion m3 of rural domestic wastewater (RDW). This study aimed to investigate the occurrence and removal of micropollutants (MPs) in RDW treatment facilities and to perform a corresponding wastewater-based epidemiology analysis (WBE). Our findings indicated the significantly high levels of influent MPs, particularly pharmaceuticals, such as ofloxacin and diclofenac being most prevalent (ranging from several to tens of μg/L) across different facilities. After various treatments, regular water indexes in the effluent, like NH3 -N and COD, have basically satisfied the local discharge standard. However, the concentration of certain dominant MPs in effluent remained notably high, ranging from hundreds of ng/L to several μg/L. The risk quotients of MPs like diclofenac, ciprofloxacin, ofloxacin, sulfamethoxazole, diuron, and isoproturon were all above 1 in the effluent, signifying significant hazards to aquatic organisms. The quantitative meta-analysis revealed higher average standardized removal efficiency for membrane bioreactor (MBR) treatment (-11 %) compared to anaerobic/anoxic/aerobic (A2O) treatment (11 %), indicating the higher efficiency of MBR treatment in outperforming the A2O as a secondary treatment. Additionally, employing biofilter as a tertiary treatment proved to be more effective as compared to flocculation-air flotation and artificial wetlands. Moreover, the results of WBE analysis showed that diclofenac and ofloxacin emerged as the most commonly used pharmaceuticals (of seven), with consumption levels recorded at 1222 and 517 mg/(d·103 capita), with daily defined doses per day per 103 capita of 12.2/1000 and 1.29/1000, respectively. This study addresses the existing knowledge gaps regarding the occurrence and removal of MPs in RDW and offers valuable insights into pharmaceutical consumption patterns in rural regions, thereby improving our understanding of public health.

Cultivation of Microalgae (Scenedesmus sp.) Using Coal Mining Wastewater and Separation via Coagulation/Flocculation and Dissolved Air Flotation (DAF)

Algae growth can be carried out in treated mine waters, providing biomass and helping to achieve the standards for water discharge. However, efficient separation of algae from the aqueous medium is crucial. The present work investigated the stability of Scenedesmus sp. in treated acid drainage from coal mining and assessed the harvesting of microalgae via coagulation/flocculation and dissolved air flotation (DAF). Successful algae growth was achieved, with cells remaining suspended in the water at a wide range of pH values, requiring the use of reagents for destabilization/aggregation. Algae coagulation/flocculation was attained with the use of tannin or ferric chloride associated with an anionic polymer flocculant at a pH of 8.0 ± 0.1. When combined with the flocculant, both tannin and the inorganic coagulant proved effective in enhancing floc stability and hydrophobicity for the DAF process. In summary, this operational approach facilitated algae biomass recovery and significantly reduced turbidity in the treated water. Finally, a schematic diagram illustrating the algae cultivation and harvesting process is presented, offering a practical alternative to acid mine drainage (AMD) treatment refinement associated with algae biomass production.

Enhancing pollutants removal in hospital wastewater: Comparative analysis of PAC coagulation vs. bio-contact oxidation, highlighting the impact of outdated treatment plants

While the effectiveness of Poly-Aluminum Chloride (PAC) coagulation for pollutant removal has been documented across various wastewater scenarios, its specific application in hospital wastewater (HWW) treatment to remove conventional pollutants and hazardous genetic pollutants has not been studied. The research compared three hospital wastewater treatment plants (HWTPs) to address a knowledge gap, including the PAC coagulation-sodium hypochlorite disinfection process (PAC-HWTP), the biological contact oxidation-precipitation-sodium hypochlorite process (BCO-HWTP), and a system using outdated equipment with PAC coagulation (ODE-PAC-HWTP). Effluent compliance with national discharge standards is assessed, with BCO-HWTP meeting standards for direct or indirect discharge into natural aquatic environments. ODE-PAC-HWTP exceeds pretreatment standards for COD and BOD5 concentrations. PAC-HWTP effluent largely adheres to national pretreatment standards, enabling release into municipal sewers for further treatment. Metagenomic analysis reveals that PAC-HWTP exhibits higher removal efficiencies for antibiotic resistance genes, metal resistance genes, mobile genetic elements, and pathogens compared to BCO-HWTP and ODE-PAC-HWTP, achieving average removal rates of 45.13%, 57.54%, 80.61%, and 72.17%, respectively. These results suggests that when discharging treated HWW into municipal sewers for further processing, the use of PAC coagulation process is more feasible and cost-effective compared to BCO technologies. The analysis emphasizes the urgent need to upgrade outdated equipment HWTPs.