Effective Wastewater Treatment Research Articles

Assessing the current situation of constructed wetland-microbial fuel cells as an alternative power generation and wastewater treatment in developing countries

Developing countries facing population growth and increased energy demand present simultaneous challenges regarding wastewater treatment and electricity supply. Constructed wetland-microbial fuel cells (CW-MFCs) offer a dual solution to the challenges of insufficient electricity and wastewater treatment by integrating indigenous plant species. CW-MFCs provide sustainable power generation and wastewater treatment. This approach can enhance sustainability and foster a circular economy by utilising plant-derived byproducts as an added product. Current research indicates various novel designs for effective wastewater treatment and potential power generation. Future studies focusing on rural settings and upscaling operations can apply advanced techniques like mass spectrophotometry and metagenomics to refine the technology for grid use. Developing CW-MFC technology will catapult the idea of developing a robust strategy for addressing power supply and sanitation issues in developing regions. This will also aid in continuous research into system optimisation and microbial communities, aiding long-term viability.

METHODOLOGY FOR QUANTITATIVE ASSESSMENT OF THE FILAMENTOUS INDEX IN TECHNOLOGIES OF BIOLOGICAL WASTEWATER TREATMENT

For the quantitative control of the filamentous index in biological treatment facilities, a computerized methodology has been developed within the presented study. Its use enhances the reliability and techno-genic safety of operating biological treatment facilities. Problems related to filamentous microorganisms, which can hinder effective wastewater treatment, are considered. Sludge bulking occurs when the intensive growth of these microorganisms complicates the separation of activated sludge from treated wastewater, leading to various operational issues. The study emphasizes the importance of microscopic analysis in identifying and addressing problems associated with filamentous organisms. The use of microscopic analysis as a crucial tool for managing activated sludge issues is discussed. The classification system developed by D. Eikelboom, which identifies 21 types of filamentous organisms based on visual characteristics, is described in detail. The filamentous index, a key parameter for monitoring the quality of activated sludge, is examined in detail, along with methods to minimize subjective evaluation factors using computer technologies. The primary goal of the study is to develop a computerized methodology for the rapid quantitative determination of the filamentous index, and area of filamentous microorganisms in activated sludge. The ImageJ software was used for processing microphotographs of sludge, enabling precise measurements of geometric characteristics. The analysis includes processing images from Eikelboom's work to establish reference values for the filamentous index. Microsoft Excel software was used for theoretical calculations and statistical analysis of experimental data. The results of the research, which confirm the effectiveness of the proposed methodologies, are presented. Keywords: activated sludge, sludge bulking, filamentous index, quantitative analysis, treatment efficiency.

Biohydrogen generation from distillery effluent using baffled up‐flow microbial electrolysis cell

AbstractMicrobial electrolysis cell (MEC) is gaining importance not only for effectively treating wastewater but also for producing hydrogen. The up‐flow microbial electrolysis cell (UPMEC) is an innovative approach to enhance the efficiency, and substrate degradation. In this study, a baffled UPMEC with an anode divided into three regions by inserting the baffle (sieve) plates at varying distances from the cathode was designed. The effect of process parameters, such as flow rate (10, 15, and 20 mL/min), electrode area (50, 100, and 150 cm2), and catholyte buffer concentration (50, 100, and 150 mM) were investigated using distillery wastewater as substrate. The experimental results showed a maximum of 0.6837 ± 0.02 mmol/L biohydrogen at 150 mM buffer, with 49 ± 1.0% COD reduction using an electrode of area 150 cm2. The maximum current density was 1335.94 mA/m2 for the flow rate of 15 mL/min and surface area of 150 cm2. The results showed that at optimized flow rate and buffer concentration, maximum hydrogen production and effective treatment of wastewater were achieved in the baffled UPMEC.Practitioner Points Biohydrogen production from distillery wastewater was investigated in a baffled UPMEC. Flowrate, concentration and electrode areas significantly influenced the hydrogen production. Maximum hydrogen (0.6837±0.02mmol/L.day) production and COD reduction (49±1.0%) was achieved at 15 mL/min. Highest CHR of 95.37±1.9 % and OHR of 4.6±0.09 % was observed at 150 mM buffer concentration.

Phytoremediation potential of Duranta erecta in cascade hydroponics for effective domestic wastewater treatment

Discharging untreated wastewater into natural water systems poses significant risks to public health, economies, and ecological stability worldwide. This study addresses these effects by investigating the phytoremediation potential of Duranta Erecta in cascade hydroponics for treating domestic wastewater. It centers on the removal of dissolved and suspended solids as well as organic matter, representing a groundbreaking effort in this domain. It involved two experimental setups: one integrating Duranta Erecta with media (gravel (EXU-1) and polyester sponge (EXU-2)), and a control setup ((gravel (COU-1) and polyester sponge (COU-2))) using only media. Each configuration consisted of three bioreactors designed to treat wastewater from Kilinto prison camp. Four hydraulic retention times (HRTs) were tested, with the 7-day HRT emerging as the most effective compared to the 1, 3, and 5-day intervals. At the 7-day HRT, experimental units one and two demonstrated substantial reductions in pollutants: suspended solids (96.50 % & 89.3 %), turbidity (94.3 % & 87.2 %), dissolved solids (49.5 % & 45.15 %), biological oxygen demand (94.57 % & 89.78 %), and chemical oxygen demand (95.44 % & 90.65 %). Statistical analysis confirmed these reductions as statistically significant (P < 0.05). These findings highlight Duranta Erecta cascade hydroponics as a promising decentralized wastewater treatment technology, particularly suitable for developing countries like Ethiopia.

Performance Evaluation of Advanced Wastewater Treatment Technologies in Herbal Processing and Extraction Industry

"Due to enormous quantities with hazards and complexity in nature is a big challenge for effective treatment of wastewater from pharmaceutical processes including herbal extraction through conventional methods of distillation. The situation is further aggravated in countries facing high rising population, urbanization, and industrialization resulting in the generation of industrial wastes. The study has been carried out in the herbal extraction industry by conducting stage-wise sampling of ETP based on the conventional method and further coupled with ozonation as an advanced treatment to comply with regulatory standards. Additionally, the same process was studied that implementing the best available technology (BAT) by providing ETP with advanced technology modules such as MBR (membrane bioreactor) + RO + O3 has not only resulted in compliance with standards but also reuse of treated wastewater into the process and utilities has been proved to be techno-economically a viable and sustainable option. Modifying existing aeration tanks and advanced oxidation through ozone injection post-biological treatment has resulted in COD and BOD reduction of 96.42% and 99.0% respectively. Whereas in the case of MBR + RO + O3, the values of pH, BOD, COD, TSS, and sulfide have been observed as 8.32, 2.0 mg.L-1, 14.0 mg.L-1, 1.0 mg.L-1 and 0.0 mg.L-1 respectively and 98% recovery of treated effluent, thus saving 44 KL.day-1 of freshwater resulting into significant financial benefits of Rupees 12.59 acs annually, which otherwise was outsourced through tankers."

Adsorption of cadmium from wastewater with activated carbons derived from pig fur biowaste: A comparative study of in-situ and ex-situ activation routes

The environmental challenges associated with cadmium contamination in wastewater have necessitated the development of high-performing activated carbons (ACs) for effective wastewater treatment. Adsorption capacity depends on both the surface area and the adsorption-active functional groups developed on the adsorbent's surface during activation. Proper manipulation of key process variables using the appropriate activation route produces highly efficient and economically viable ACs. This research investigates the viability of pig fur biowaste as a novel precursor for activated carbons using two distinct activation methods—in-situ and ex-situ. Using a central composite design (CCD) of the Response Surface Methodology (RSM), the study systematically examines the effects of impregnation ratio, carbonization temperature, and carbonization time on the cadmium adsorption capacities of the resulting ACs. The optimal conditions for in-situ activation were found to be 691 °C, 175.11 min, and an impregnation ratio of 1.784 g/g, resulting in a cadmium adsorption capacity of 91.57 %. For ex-situ activation, the optimal conditions were 468.8 °C, 80.81 min, and an impregnation ratio of 2.915 g/g, which achieved a higher cadmium adsorption capacity of 91.21 %. Both types of activated carbons maintained high efficiency after five regeneration cycles, indicating they are suitable for long-term applications requiring repeated regeneration. Although both methods produced ACs with comparable cadmium removal efficiency, the ex-situ activation route proved to be more economically viable due to its lower temperature and shorter processing time. This study demonstrates the potential of pig fur biowaste as a sustainable and underutilized resource for AC production and highlights the ex-situ activation route as the more cost-effective approach for producing high-performance adsorbents.

A highly efficient and stable PtNi bimetallic nanoparticles modified on Mo2C decorated N-doped carbon flowers catalysts for the remediation of environmental pollutants

The unregulated discharge of nitroaromatics (NAs) and organic dye contaminants into aquatic ecosystems is a growing global concern, highlighting the urgent need for the development of effective wastewater treatment technology. In this study, we prepared Mo2C decorated on N- doped carbon flowers supported with PtNi bimetallic (PtxNiy@Mo2C/NCF) nanoparticles using the self-polymerization of dopamine and followed by the chemical reduction methods. These catalysts, with varying Pt:Ni ratios, were designed for the highly efficient catalytic reduction of NAs and rhodamine b (RhB) under the mild reaction conditions. The HR-TEM images confirmed the formation of spherical PtNi bimetallic NPs with an average diameter of 1.68 ± 0.6 nm. The prepared PtxNiy@Mo2C/NCF catalysts exhibited significantly higher catalytic efficiency for 4-nitrophenol (4-NP) reduction compared to their respective monometallic counterparts using NaBH4. Particularly, the Pt0.75Ni0.25@Mo2C/NCF catalyst showed superior catalytic activity with the apparent rate constant (kapp: 0.6703 min−1) and TOF (17.0 × 10−7 mol mg−1 min−1) and high recyclability over eight consecutive recycles. Furthermore, the Pt0.75Ni0.25@Mo2C/NCF catalyst also exhibited high catalytic activity for other NAs and RhB dye reduction with excellent yields. This enhanced catalytic activity of Pt0.75Ni0.25@Mo2C/NCF catalyst could be ascribed to the synergistic effect of the bimetallic systems, leading to more efficient reactions. Additional experiments were conducted on a fixed bed reactor to demonstrate that the Pt0.75Ni0.25@Mo2C/NCF catalyst effectively reduce both 4-NP and RhB dye over 15 successive runs. This work may pave the way for using PtxNiy@Mo2C/NCF catalysts in various wastewater treatment applications.

Study on Methylene Blue Adsorption Properties of Biochar/Montmorillonite Composites

The textile printing and dyeing industry, as one of the important pillars of the global economy, has become an environmental problem that needs to be solved because of the increasingly serious pollution of dye wastewater generated during its production process. Dye wastewater not only contains high concentrations of organic dyes, but also often accompanied by heavy metal ions, additives and salts and other pollutants, if discharged directly without effective treatment, will seriously pollute the water body, destroying the ecological balance, and affecting the survival and health of human beings and aquatic organisms. In order to deal with the problems of serious pollution, large discharge and high cost of dye wastewater, it is necessary to develop an efficient, economic and environmentally friendly wastewater treatment system. It is particularly important to develop efficient, economical and environmentally friendly wastewater treatment technologies. Adsorption is considered as a promising method for wastewater treatment. In this study, we focused on the development of new and efficient adsorbent materials. Taking methylene blue, a typical dye, as an example, we skillfully composited modified biochar with montmorillonite, a natural mineral material, through pyrolysis and intercalation strategies, and conducted in-depth investigations on the effects of the composites on the adsorption of methylene blue in water, the factors affecting the regeneration performance of the adsorbents, and the thermodynamic characteristics of the adsorption. The effect of the composite material on the adsorption of methylene blue in water, the factors affecting the regeneration performance of the adsorbent and the adsorption thermodynamic characteristics were investigated in depth, with a view to providing certain theoretical and practical references for the effective treatment of dye wastewater.

Zero-dimensional quantum dot-modified membrane materials for the effective treatment of industrial wastewater: A comprehensive review

The efficient treatment and recycling of industrial wastewater is an important way to improve water resource utilization. Membrane separation technology has been widely used in the field of industrial wastewater treatment due to its high separation efficiency, low energy consumption, good scalability, and other advantages. A recent breakthrough in membrane technologies is the emergence of various nanocomposite membranes, which not only breaks the trade-off between membrane selectivity and permeability, but also enhances the anti-fouling ability and multi-scale separation effects of membranes. Among the nanomaterials used for membrane fabrication, zero-dimensional quantum dots (QDs) with size-dependent optical properties and excellent photocatalytic potential have become promising candidates for novel nanocomposite membrane construction. Significant improvements in membrane surface hydrophilicity, anti-fouling property, and permeability can be achieved by incorporating QDs during the membrane formation process or through membrane post-modification. This review focuses on recent advances in QD-modified membranes for industrial wastewater treatment. The synthesis methods of QDs were summarized firstly, especially for carbon-based and semiconductor QDs. Based on the blending modification and surface modification, the research progress in the modification strategies of QD-modified membranes is presented. Subsequently, the state-of-the-art studies of QD-modified membranes in the application of industrial wastewater treatment are reviewed. Finally, the current challenges and opportunities in QD-modified membranes are discussed.

Adsorption of Polycyclic Aromatic Hydrocarbons from Wastewater Using Iron Oxide Nanomaterials Recovered from Acid Mine Water: A Review

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic pollutants known for their persistence and potential carcinogenicity. Effective removal techniques are required since their presence in wastewater poses serious threats to human health and the environment. In this review study, iron oxide nanomaterials (IONs), a by-product of mining operations, recovered from acid mine water are used to investigate the adsorption of PAHs from wastewater. The mechanisms of PAH adsorption onto IONs are investigated, with a focus on the effects of concentration, temperature, and pH on adsorption efficiency. The better performance, affordability, and reusable nature of IONs are demonstrated by comparative studies with alternative adsorbents such as activated carbon. Economic and environmental ramifications highlight the benefits of employing recovered materials, while case studies and real-world applications show how effective IONs are in removing PAHs in the real world. This review concludes by discussing potential future developments in synthesis processes, areas for more research, and emerging trends in nanomaterial-based adsorption. This research intends to contribute to the development of more effective and sustainable wastewater treatment technologies by offering a thorough assessment of the present and future potential of employing IONs for PAH removal from wastewater.

The efficacy of integrated vermifiltration technology for treatment of food analysis laboratory wastewater

The macrophyte-assisted vermifiltration (MAVF) technology was applied for treatment of food analysis laboratory wastewater at Industrial Technology Institute (ITI), Sri Lanka for the first time. Three laboratory-scale sub-surface vertical flow units were established:1) without earthworms and plants (Control unit), 2) with earthworms (Eisenia fetida) (vermi-filtration unit (VF unit), 3) with both earthworms and macrophytes (Canna indica) (MAVF unit). Wastewater was fed batch-wise with a feeding rate of 10 mL/min and seven days hydraulic retention time (HRT) for eight consecutive batches. Physiochemical parameters, Chemical Oxygen Demand (COD), Total Phosphorus (TP), Total Nitrogen (TN), pH, of the influent and effluent of all three units were analyzed to investigate the treatment efficiencies. One-Way ANOVA was performed to evaluate the significant differences in treatment efficiencies. The mean COD removal efficiencies of the control unit, VF unit, and MAVF unit were 60.2 % ± 10.7, 71.6± 8.07 %, and 72.0 % ± 8.86, respectively. Average TN removal efficiencies of the control unit, VF unit, and MAVF unit were 8.05 % ± 5.75, 10.9±6.4 %, and 24.9 % ±12.84, respectively. Average TP removal efficiencies were 35.84 % ± 17.5, 35.84 % ± 17.5 %, and 40.0 % ±16.76, respectively. The COD removal displayed promising results, whereas the means for enhancing TP and TN removal should be further studied. The findings of this study sensitizes the testing laboratories to go green by adopting in-house cost effective laboratory wastewater treatment systems.

Efficiency of EMB Medium Combined with MALDI-TOF in Isolating and Identifying Coliform Lactose Fermenters and Non-Lactose Fermenters from Wastewater

In Côte d'Ivoire, the sewer network is largely underdeveloped, resulting in the absence or incompleteness of sanitation infrastructure in many urban and rural areas. This lack of infrastructure leads to untreated wastewater being frequently discharged into rivers and other sources of drinking water. The contamination of water sources by untreated wastewater spreads waterborne diseases, which particularly affect children and vulnerable populations. Coliforms, as key indicators of the microbiological quality of water, play a crucial role in assessing health risks. The presence and diversity of these coliforms can provide insights into the extent of water contamination and the potential health risks to the population. This study focuses on the diversity of lactose-fermenting and non-lactose-fermenting coliforms in the wastewater of Abidjan. The objective is to use MALDI-TOF mass spectrometry for the rapid and accurate identification of these coliforms, thereby providing a detailed understanding of the microbiological quality of wastewater. The study aims to identify the predominant coliform species present in the wastewater and assess their potential impact on public health. Out of 80 wastewater samples collected from various locations in Abidjan, a preponderance of lactose-fermenting coliforms was found. The most frequently identified species were Klebsiella pneumoniae and Escherichia coli. The results showed that these species were present in significantly higher numbers compared to non-lactose-fermenting coliforms. The use of MALDI-TOF mass spectrometry allowed for rapid and precise identification of the coliforms, facilitating a comprehensive analysis of the microbiological quality of the wastewater. These findings underscore the urgent need for improved wastewater management strategies in Abidjan and similar urban settings in Côte d'Ivoire. The high prevalence of lactose-fermenting coliforms, particularly Klebsiella pneumoniae and Escherichia coli, in untreated wastewater poses significant public health risks. Effective wastewater treatment and management are essential to protect public health, reduce the spread of waterborne diseases, and limit the development of antimicrobial resistance. Implementing such measures will require coordinated efforts from local authorities, public health officials, and the community to ensure safe and sustainable water practices.

Optimisation of Water-Use in Pulp and Paper Mills: A Streamlined Review of Scientific Journal Publications

The water-, and energy footprints of the processes in the pulp and paper industry are sizable enough to warrant investment of money and commitment of time truncate the same. Besides, there is also a nexus between water and energy here, with optimisation of the use of one of these resoruces enabling that of the other too. This streamlined review focuses on journal publications (originating from different parts of the world, and targeted at researchers and decision-makers in the industry) which train the lens on the optimisation of water use in this particular sector of the (forestry) bioeconomy. The synergies and complementarities which exist among different sustainable development goals (SDGs) , promise positive ripple effects, caused by attending to the truncation of the water footprint. The articles, in general, recommend effective in-plant wastewater treatment in combinaton with recirculating the treated effluent, and looking upon the water streams as carriers or bearers of valorisable substances – organics which can yield a host of bio-products in bio-refineries, including bio-energy. Availing of water-pinch analysis as a tool to uncover possibilities of water use in a cascade (depending upon the requirements imposed on the water, by processes downstream in the cascade), has been shown to aid in the optimisation of both water use and energy demand within the plant. One case study, for example, showed that the demand for steam can be decreased by about 4 GJ per ton of output, by recovering the waste heat in the water streams.

Nitrogen metabolism network in the biotreatment combination of coking wastewater: Take the OHO process as a case

As steel production increases, large volumes of highly toxic and nitrogen-rich coking wastewater (CWW) are produced, prompting the development of a novel oxic-hydrolytic-oxic (OHO) biological treatment combination designed for highly efficient removal of nitrogen-contained contaminants. However, previous studies have not comprehensively explored the CWW biotreatment from the perspective of nitrogen metabolism functional genes and pathways. Based on the investigation of taking the full-scale OHO biotreatment combination as a case, it was found that the O1 and O2 bioreactors remove nitrogen through the ammonia assimilation accounting for 33.87% of the total nitrogen (TN) removal rate, while the H bioreactor removes nitrogen through the simultaneous nitrification-denitrification accounting for 61.11% of the TN removal rate. The major ammonia assimilation taxa include Thauera, Immundisolibacter and Thiobacillus; the major nitrifying taxa include Nitrospira and Nitrosomonas; and the major denitrifying taxa include Thiobacillus, Lautropia and Mesorhizobium. Additionally, the H bioreactor exhibits the potential to be optimized for simultaneous nitrification-denitrification coupled with anaerobic ammonium oxidation (Anammox). These understandings will guide the optimization of engineering design and operational practices, contributing to more effective and sustainable wastewater treatment strategies.

Innovative potassium hexacyanoferrate intercalated into layered double hydroxide adsorbent for efficient cesium removal from seawater

Effective radioactive wastewater treatment technology is essential to ensure the sustainable development of nuclear energy. Here, the potassium ferrocyanide (HCF) intercalating with layered double hydroxide (LDH) (HCF@LDH) was successfully synthesized by coprecipitation method for selective cesium (Cs) removal from seawater. Characteristics of the adsorbent, and adsorption performance under different environmental conditions including Cs+ ion selectivity, and underlying adsorption mechanism were systematically investigated. The experimental results demonstrated that the adsorption capacity of HCF@LDH was 52.08 mg/g and it effectively removed 100 % of Cs+ from up to 200 mg/L Cs solution within 1 h under an optimal pH of 6.0–10.0. Moreover, the adsorbent displayed high selectivity towards Cs+ even in seawater and more than 90 % of Cs+ was removed from seawater and the highest cesium removal capacity from seawater was 44.64 mg/g. Both the Langmuir isotherm model (R2 = 0.997) and the pseudo-second-order kinetic model (R2 = 0.999) provided a good fit for the adsorption data signifying the adsorption process is homogeneous and formed monolayer through chemisorption. Furthermore, the reusability analysis exhibited this adsorbent was recycled and reused for at least 5 cycles without losing its original adsorption performance. The physicochemical analysis of the HCF@LDH proved that K4Fe (CN)6 successfully intercalated onto LDH and cation exchange between K+ and Cs+ played an important role in effective Cs adsorption. More specifically, the interstitial spaces of the hexacyanoferrate crystals facilitate the cation exchange process. The findings of this study demonstrate that HCF@LDH is a unique, highly effective, and selective adsorbent for Cs+ from complex seawater.

The use of biofilters in the treatment of wastewater containing organic substances

Abstract The lack of sufficiently effective treatment of wastewater generated in industry and domestic life remains one of the most acute environmental problems. Domestic wastewater is characterized by a high content of organic impurities in its composition, which determines the specifics of the choice of treatment technologies. One of the most relevant and effective methods is biological purification carried out in biological filters. This article discusses the problems associated with wastewater treatment of a sanatorium compound. The analysis of the content of various components in the water supplied to the treatment was carried out, the efficiency of the treatment equipment was determined. The paper proposes and substantiates the expediency of using a modern type of synthetic ruff biofilter media to increase the cleaning efficiency of the wastewater and their compliance with regulatory requirements for discharge into a water body.

Mitigating environmental pollution from tofu industry wastewater: Case of Suyanto Tofu Factory, Mojokerto

Background: This research investigates the impact of tofu industry wastewater on water environments at Suyanto Tofu Factory, Mojokerto. The tofu industry generates liquid waste containing high pH, Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD), and Chemical Oxygen Demand (COD), potentially polluting local rivers. Despite Suyanto Tofu Factory having wastewater treatment facilities, these are currently non-functional, underscoring the urgent need for designing new wastewater treatment installations. Methods: In this context, the study aims to determine the volume of wastewater produced, analyze the levels of BOD, COD, TSS, and pH in the wastewater, and design sustainable wastewater treatment facilities using a Constructed Wetland system. Findings: This method is expected to minimize the environmental impact of tofu wastewater, protect surrounding aquatic ecosystems, and comply with environmental regulations. By proposing sustainable solutions, the research aims to enhance awareness and management of wastewater in the tofu industry, offering technology solutions appropriate to local conditions. Conclusion: In conclusion, implementing effective and sustainable wastewater treatment installations is crucial to safeguard water quality and river ecosystems around Suyanto Tofu Factory. Novelty/Originality of this Study: By proposing a Constructed Wetland system for tofu industry wastewater treatment, this research introduces an innovative, sustainable solution tailored to local conditions, potentially revolutionizing waste management practices in small-scale food industries.

Evaluating The Effectiveness of Wastewater Treatment In the Reusable Packaging Industry: A Case Study of ALNER’S WWTP In Indonesia

The widespread use of single-use plastic packaging has become a significant environmental issue, particularly in the Global South. This study examines the innovative approach of the startup Alner, which employs a combination of electrochemical treatment and Moving Bed Biofilm Reactor (MBBR) technology in its wastewater treatment plant (WWTP) to manage wastewater generated from the cleaning of reusable packaging. Wastewater samples were collected before and after treatment, and analyzed for key parameters such as Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5), Total Suspended Solids (TSS), oil and grease, ammonia, surfactants, and phosphates. The results demonstrated a significant reduction in all measured pollutants, with COD reduced by 99.58% and BOD5 by 99.56%. Post-treatment values for all parameters were well within the regulatory limits set by the Ministry of Environment and Forestry Regulation No. P68/MenLHK/Setjen/Kum.1/8/2016. This study underscores the potential of reuse models in reducing single-use plastic waste and highlights the importance of effective wastewater treatment in maintaining environmental sustainability. Alner's approach provides a scalable and environmentally friendly solution, setting a benchmark for similar initiatives in the industry, and supports the feasibility and sustainability of integrating advanced wastewater treatment technologies in the reusable packaging sector, offering a comprehensive solution to plastic pollution.

Iron-retrofitted anaerobic baffled reactor system for rural wastewater treatment: Stable performance of nutrients removal with phosphorus recovery and minimal sludge production

An iron-retrofitted anaerobic baffled reactor (ABR) system was developed for the effective treatment of rural wastewater with reduced maintenance demand and aeration costs. Average removal efficiencies of chemical oxygen demand, total nitrogen and total phosphorus of 99.4%, 62.7% and 92.6% were achieved respectively, when the ABR system was operating at steady state. With effective bioreduction of FeIII in the anaerobic chambers, phosphorus was immobilized in the sludge as vivianite, the sole phosphorus-carrying mineral. The FeIII in the recirculated sludge induced Feammox in the ABR reactor, contributing 14.8% to total nitrogen removal. Biophase separation and enrichment of microorganisms associated with iron and nitrogen transformations were observed in the system after Fe dosing, which enhanced the removal of pollutants. The coupling of Feammox and vivianite crystallization to remove nitrogen and phosphorus in an iron-retrofitted ABR would appear to be a promising technology for rural wastewater treatment.

Waste newspaper as cellulose resource of activated carbon by sodium salts for methylene blue and congo red removal

The work was aimed at evaluating the adsorptive properties of waste newspaper (WN) activated carbons chemically produced using sodium salts for methylene blue (MB) and congo red (CR) removal. The activated carbons, designated as AC1, AC2, AC3 and AC4 were prepared through impregnation with NaH2PO4, Na2CO3, NaCl and NaOH, respectively and activation at 500 °C for 1 h. The activated carbons were characterized for surface chemistry, thermal stability, specific area, morphology and composition. The AC1 with a surface area of 917 m2/g exhibits a greater MB capacity of 651 mg/g. Meanwhile, a greater CR capacity was recorded by AC2 at 299 mg/g. The pseudo-second order model fitted well with the kinetic data, while the equilibrium data could be described by Langmuir model. The thermodynamic parameters, i.e.., positive ΔH°, negative ΔG° and positive ΔS° suggest that the adsorption of dyes is endothermic, spontaneous and feasible at high solution temperature. To conclude, WN is a potential cellulose source for producing activated carbon, while NaH2PO4 activation could be employed to convert WN into activated carbon for effective dye wastewater treatment.