Treatment Of Industry Wastewater Research Articles

Confirmatory factor analysis for the implementation of Green Lean Six Sigma (GLSS) in Malaysia's wastewater treatment industry

ABSTRACT This study investigates the critical enablers influencing the implementation of Green Lean Six Sigma (GLSS) in Malaysia's wastewater treatment industry. Through an extensive literature review and insights from the industry, 30 distinct enablers were identified and categorized based on their characteristics within wastewater treatment plant (WWTP) organizations, aimed at ensuring successful GLSS execution. Structural equation modelling was employed to validate the research model, utilizing data from 296 certified professionals in Malaysia. The analysis revealed five significant enablers, indicating moderate to high levels of GLSS adoption within the industry, with the ‘strategic’ and ‘resource’ enablers emerging as particularly influential factors. Subsequent confirmatory factor analysis further affirmed the validity and reliability of these enablers. Moreover, the findings demonstrated both convergent and discriminant validity, reinforcing the efficacy of these factors in measuring GLSS implementation in Malaysian WWTPs. The study highlights the critical importance of strategic planning and resource allocation while emphasizing the need to address cultural and environmental factors for successful GLSS adoption in the industry. However, enablers based on linkages, particularly those pertaining to supplier relationships and customer satisfaction, garnered the least consensus among respondents, indicating areas necessitating further attention and improvement.

Mathematical Modeling and Indirect Carbon Emission Reduction Analysis of Urban Wastewater Treatment Systems Under Different Temperature Conditions

In the context of achieving the two-carbon target, this study utilized a wastewater treatment plant in Shenyang City as a case study to accurately calculate indirect emissions related to energy and chemical consumption within the energy-intensive wastewater treatment industry. Sumo software was employed for precise mathematical modeling. Considering the operational characteristics of wastewater treatment plants in cold regions, this study innovatively divided the annual operation cycle into two periods, namely normal temperature and low temperature, and determined the optimal operational parameters under a low-carbon mode. The results indicate that precise regulation of dissolved oxygen concentration to 0.5–1.5 mg/L (normal temperature period) and 1–2 mg/L (low temperature period) can significantly reduce carbon emissions related to electricity consumption by 13,781.9 t CO2-eq. From the perspective of chemical consumption, adjusting the dosage of polyaluminum chloride (PAC) to 75% and sodium acetate to 70% during the normal temperature period can lead to a reduction in indirect carbon emissions of 1614.4 t CO2-eq compared to the same period last year. During the low-temperature period, by reducing the dosage of polyaluminum chloride to 80% and sodium acetate to 75%, the indirect carbon emissions can be reduced by 1557.3 t CO2-eq compared to the corresponding period last year. After optimization, USD 1.49 million can be saved. This study simulated the operation conditions of cold-region urban wastewater treatment plants at different times to effectively control carbon emissions resulting from energy and chemical consumption in wastewater treatment. This result can provide innovative ideas for energy saving and carbon reduction in cold-region wastewater treatment plants.

Advanced Oxidation Technology Using Fe0/H2O2 as an effective treatment for recycling industrial wastewater for irrigation of Lolium perenne crops.

This study focused on developing a new Phenton treatment of water effluent coming from a local industrial estate and staining industry site. Different advanced oxidation technologies (AOTs) such as heterogeneous photocatalysis, Photo-Fenton and UV-Vis/H2O2 using FeSO4, and pure iron were evaluated. To develop this study, water samples were tested before and after each treatment. In general, after AOTs the amount of chlorides, nitrates, hydrocarbons, heavy metals, TOC and bacteria significantly decreased. Photo-Fenton and UV-Vis/H2O2/TiO2 showed the best performance in the treatment of staining industry and industrial wastewater, respectively. Photo-Fenton mineralized 100% of dyes, reduced by 99% total coliforms, eliminated 76% of TOC and 60% of heavy metals tested. Interestingly, use of iron metal in the Photo-Fenton treatment was found to achieve similar results. This means wastewater can be treated with benign chemicals. Treated wastewater was evaluated as a potential water source for the irrigation of Lolium perenne, a conventional crop in animal feed. In general, the physical characteristics of Lolium perenne such as leaf and roof length and width, were not significantly modified after irrigation with treated wastewater. Similar results were obtained using treated tap water as reference. A trace number of metals remaining from treatment was detected in grass and soil. However, the concentration of Cd, Cr, Cu, and Zn was very similar to tap water. Considering these outcomes, use of non-toxic zero valent iron metal and hydrogen peroxide in a Photo-Fenton reaction is a pilot plant scalable alternative oxidating treatment technology for recycling industrial wastewater in agricultural activities.Top of Form

Bioinspired interlaced wetting surfaces for continuous on-demand emulsion separation

Maintaining high separation performance during continuous emulsion separation remains a challenge. Herein, based on biomimetic coupling ideas, hole array interlaced wetting surfaces (HAIWSs) and mastoid array interlaced wetting surfaces (MAIWSs) were prepared by laser processing, electroless silver deposition, thiol modification, and spraying for on-demand emulsion separation. When the separation is going on, randomly moving emulsion droplets are prone to being captured by holes or mastoids due to interlaced wettability. Under this unique interface behavior, the occurrence of filter cake and pore clogging is reduced, thus achieving both high efficiency (∼99.5 and ∼99.3 %). Meanwhile, the high flux can also be maintained (∼3212 and ∼3458 L m−2 h−1). Significantly better than surfaces without pores or mastoid structures. Further, the as-prepared surfaces also exhibit excellent recyclability. After 50 separation cycles, optimized HAIWS and MAIWS still maintained high efficiency (∼96.2 and ∼95.8 %) and high flux (∼3042 and ∼3164 L m−2 h−1), exceeding other surfaces without hole or mastoid structure. Notably, complex physical/chemical cleaning processes are avoided. Besides, even in harsh conditions, HAIWS and MAIWS still maintain excellent stability. The above strategy provides a novel mechanism for effective on-demand emulsion separation and is expected to encourage the creation of new-class separation devices for oily wastewater treatment in industry.

The Synergistic Power of Rosehip Seed Powder and Aluminum Chloride in Steel Industry Wastewater Treatment

This study investigates the efficiency of a hybrid coagulation–flocculation process for the treatment of industrial wastewater from the steel industry. The novel method combines a natural coagulant, processed Rosehip Seed Powder (RSP), with a chemical coagulant, aluminum chloride (AlCl3), across varying concentrations and pH levels. The study simulated the pH 8 conditions of iron and steel industrial wastewater and examined the removal of heavy metals, total suspended solids (TSS), chemical oxygen demand (COD), and ammonia–nitrogen (NH3-N). At pH 8, the optimal coagulant dosage was determined to be 0.75:0.75 (g/g) of RSP/AlCl3 powder, resulting in high removal efficiencies across several parameters: 88.29% for COD, 91.85% for color, 99% for TSS, 93.11% for NH3-N, 94.3% for Mn, 98.5% for Fe, 96.7% for Zn, and 99.3% for Ni. The pH optimization demonstrated high removal efficiencies without pH adjudication. The removal of heavy metals at pH 8 demonstrated high efficiencies, with Mn, Fe, Zn, and Al achieving 99.00%, 90.6%, 95.73%, and 92.3%, respectively. These results suggest that no pH adjustment is required when using RSP/AlCl3 for the treatment of iron and steel industry wastewater through the coagulation method.

Industrial activated sludge model identification using hyperparameter-tuned metaheuristics

This study focuses on the parameter estimation of an industrial activated sludge model using hyperparameter-tuned metaheuristic techniques. The data used in this study were collected on-site from a textile industry wastewater treatment plant. A Modified Activated Sludge Model (M-ASM) was the 'first-principle model’ selected and implemented with suitable assumptions. Advanced metaheuristic techniques, as Adaptive Tunicate Swarm Optimization (ATSO), Whale Optimization Algorithm (WOA), Rao-3 Optimization (Rao-3) and Driving Training Based Optimization (DTBO) were implemented. The hyperparameter tuning was performed with Bayesian Optimization (BO). Optimized metaheuristic algorithms were implemented for model-parameter identification. The Bayesian optimized Rao-3(BO-Rao-3) algorithm provided the best validation results, with a Mean Absolute Percentage Error (MAPE) value of 7.0141 and Normalized Root Mean Square Error (NRMSE) value of 0.2629. It also had the least execution time. BO-Rao-3 is 0.93% to 4.7% better than the other implemented hyperparameter-tuned metaheuristic techniques.

Streptomyces as a Novel Biotool for Azo Pigments Remediation in Contaminated Scenarios.

Azo pigments are widely used in the textile and leather industry, and they generate diverse contaminants (mainly in wastewater effluents) that affect biological systems, the rhizosphere community, and the natural activities of certain species. This review was performed according to the Systematic Reviews and Meta Analyses (PRISMA) methodology. In the last decade, the use of Streptomyces species as biological azo-degraders has increased, and these bacteria are mainly isolated from mangroves, dye-contaminated soil, and marine sediments. Azo pigments such as acid orange, indigo carmine, Congo red, and Evans blue are the most studied compounds for degradation, and Streptomyces produces extracellular enzymes such as peroxidase, laccase, and azo reductase. These enzymes cleave the molecule through asymmetric cleavage, followed by oxidative cleavage, desulfonation, deamination, and demethylation. Typically, some lignin-derived and phenolic compounds are used as mediators to improve enzyme activity. The degradation process generates diverse compounds, the majority of which are toxic to human cells and, in some cases, can improve the germination process in some horticulture plants. Future research should include analytical methods to detect all of the molecules that are generated in degradation processes to determine the involved reactions. Moreover, future studies should delve into consortium studies to improve degradation efficiency and observe the relationship between microorganisms to generate scale-up biotechnological applications in the wastewater treatment industry.

Energy self-sufficiency and carbon neutrality potential of Chinese urban wastewater treatment

The implementation of some energy-saving and emission reduction measures can effectively offset the energy consumption and carbon emissions in the wastewater treatment process. Integrated policy-making information on carbon-energy-economy of these technologies is not clear in national wastewater treatment industry. This study investigated energy self-sufficiency, carbon neutralization potential and economic performance of wastewater treatment industry, as well as related synergy effect among the three aspects using the proposed approach. Then the approach was used to investigate energy-saving and carbon emission reduction potential of the three technologies (photovoltaic power (PV), combined heat and power (CHP) and water source heat pump (WSHP)) and technological combinations as well as related economic performance in urban wastewater treatment of Chinese different provinces in 2021. The results showed that (1) The national energy self-sufficiency is 95%; therein, 13 provinces have the potential to achieve or exceed energy self-sufficiency of 100%, and the top 3 provinces are Heilongjiang, Yunnan and Hunan. (2) The national carbon neutral potential is 87%; therein, 9 provinces have the potential to achieve or surpass carbon neutralization of 100%, and the top 3 provinces include Beijing, Hunan and Shaanxi. (3) these technologies or their combinations are potentially economically viable (net economic benefit ratio >1), and the top three provinces are Beijing, Shaanxi, and Inner Mongolia. (4) Generally, there are 13 provinces with synergy effect >1 in the country; the top three provinces are Liaoning, Heilongjiang and Hunan. Finally, targeted policy suggestions are provided for Chinese urban wastewater treatment. The proposed approach can also act as one of decision-making tools for wastewater treatment industry in other countries or areas in the world.

Autotrophic biological nitrogen removal in anammox system at elevated temperature: EPS regulation and metagenomic analysis

Carbon reduction in wastewater treatment industry has been attracted global attention. Anaerobic ammonium oxidation (anammox) process is known as a promising and energy-efficient technology. In this study, the effects of elevated temperature on anammox system were thoroughly investigated. Analyses of effluent and microbial community indicated that long-term exposure to 45℃ led to system collapse and a huge shift in community structure. Network analysis revealed that the sudden drop in abundance of AnAOB at 45℃ (from 36.19 % to 10.71 %) made them uncompetitive with heterotrophic bacteria. The decrease of EPS concentration (a minimum of 7.22 mg·g−1-VSS at 45℃) combined with the enhancement of EPS metabolism at higher temperature suggested a shift in the role of EPS from protective function at 35℃ to utilization as a carbon source for heterotrophic bacteria at higher temperatures. Through constructing the cross-feeding relationships associated with amino acids, polysaccharides, and cofactors, we found the dependence of heterotrophs on AnAOB became weaker at high temperature, and the disturbances in interspecific relationships might be responsible for the collapse of the anammox system. This work presents significant insights into the engineering of anammox process under high temperature.

Performance of Dairy Factory Wastewater Treatment Plant (Case Study of Pasuruan Dairy Factory East Java)

The 'ILP' company produces bottled milk with chocolate, melon, strawberry, and vanilla flavors in colorless HDPE (High-Density Polyethylene) plastic bottles and aluminum foil covers. The 'ILP' dairy industry wastewater treatment process stages include bar screen, grease trap, equalization tank, flocculation-coagulation, primary clarifier, aeration tank/activated sludge, and secondary clarifier. The research aims to determine the performance of the dairy factory's WWTP (Wastewater Treatment Plant) in terms of TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) parameters. This field-scale research was carried out for approximately 5 weeks (35 days) at the wastewater treatment plant of the ILP company. Wastewater sampling is carried out at the inlet point, equalization tank, primary sedimentation, aeration tank, and outlet point of WWTP. Wastewater examination conducted in the company's internal laboratory, including temperature, pH, total suspended solids (TSS), and chemical oxygen demand (COD). The dairy factory WWTP (wastewater treatment plant) can generate TSS (total suspended solids) effluent of 22 mg/L and COD (chemical oxygen demand) of 26.8 mg/L to meet the applicable wastewater quality standards. The treatment efficiency of the dairy industry WWTP for TSS is 94.7% and COD is 98.1%.

Modified Cellulose-Based Waste for Enhanced Adsorption of Selected Heavy Metals from Wastewater.

Due to industrial growth and its impact on the environment, the increasing amount of industrial waste requires a comprehensive approach aligned with the principles of sustainable development. The main goals are not only to preserve natural resources but also to encourage innovation in the reuse of waste materials. In an attempt to reduce the problems regarding waste disposal and wastewater treatment in the textile industry, fibrous textile waste was used as a starting material to obtain carbon adsorbents for the removal of pollutants from wastewater. Waste cotton and mixed yarns, mainly consisting of polysaccharide cellulose, were hydrothermally carbonized and activated with KOH to convert them into efficient carbon adsorbents for heavy metal removal from water. Characterization of carbonized material showed that after activation, an increase in specific surface area (up to 872 m2/g) and content of surface oxygen groups (6.04 mmol/g) leads to a higher affinity towards heavy metal ions, especially lead ions, and high adsorption capacity of 19.98 mg/g obtained for activated cotton yarns. The results of this research represent a contribution to the reduction of waste materials by modifying them into adsorbents, while the regeneration of adsorbents is an example of the practical application of polysaccharide-based materials in the purification of wastewater containing various heavy metal ions.

Impact of untreated tannery wastewater in the evolution of multidrug-resistant bacteria in Bangladesh

The tannery industry produces one of the worst contaminants, and unsafe disposal in nearby waterbodies and landfills has become an imminent threat to public health, especially when the resulting multidrug-resistant bacteria and heavy metals enter community settings and animal food chains. In this study, we have collected 10 tannery wastewater (TWW) samples and 10 additional non-tannery wastewater (NTW) samples to compare the chemical oxygen demand (COD), pH, biological oxygen demand (BOD), dissolved oxygen (DO), total dissolved solids (TDS), chromium concentration, bacterial load, and antibiotic resistance profiles. While COD, pH, and chromium concentration data were previously published from our lab, this part of the study uncovers that TWW samples had a significantly higher bacterial load, compared to the non-tannery wastewater samples (5.89 × 104 and 9.38 × 103 cfu/mL, respectively), higher BOD and TDS values, and significantly lower DO values. The results showed that 53.4, 46.7, 40.0, and 40.0% of the TWW isolates were resistant to ceftriaxone, erythromycin, nalidixic acid, and azithromycin, respectively. On the other hand, 20.0, 30.0, 50.0, and 40.0% of the NTW isolates were resistant to the same antibiotics, respectively. These findings suggest that the TWW isolates were more resistant to antibiotics than the NTW isolates. Moreover, the TWW isolates exhibited higher multidrug resistance than the NTW isolates, 33.33, and 20.00%, respectively. Furthermore, spearman correlation analysis depicts that there is a negative correlation between BOD and bacterial load up to a certain level (r = − 0.7749, p = 0.0085). In addition, there is also a consistent negative correlation between COD and bacterial load (r = − 0.7112, p = 0.0252) and TDS and bacterial load (r = − 0.7621, p = 0.0104). These findings suggest that TWW could pose a significant risk to public health and the environment and highlight the importance of proper wastewater treatment in tannery industries.

Using a novel bio-based cationic flocculant for food industry wastewater treatment

Wastewater from the food industry is considered harmful to human health and aquatic life, as well as polluting water and soil. This research is centered around finding an affordable and easy physicochemical method for dealing with waste generated by the food industry. To accomplish this goal, a new bio-based flocculant called 4-benzyl-4-(2-oleamidoethylamino-2-oxoethyl) morpholin-4-ium chloride was created using sustainable sources, specifically crude olive pomace oil. Its chemical structure was confirmed using various spectroscopic techniques such as FTIR, 1H-NMR, mass spectra, and 13C-NMR. This new bio-based cationic flocculant was combined with alum to act as a coagulant in the waste treatment process. Also, a study was conducted to determine the optimal conditions for the coagulation-flocculation process parameters, namely, pH and alum dosage, on COD and removal efficiency. The results showed that the optimal conditions for flocculation were achieved at pH 5.8, with 680 mg/L alum and 10 mg/L of commercial flocculant dose compared to only 5 mg/L of a new bio-based cationic flocculant. A comparison was made between the new bio-cationic flocculant and a commercial CTAB one for treating wastewater in the food industry. The study found that the new bio-based cationic flocculant was more effective in reducing the chemical oxygen demand, achieving a reduction of 61.3% compared to 54.6% for using a commercial cationic flocculant. Furthermore, using a new bio-based cationic flocculant costs only 0.49 $/g, which is less than the present cationic flocculant, which costs 0.93 $/g. The adoption of this new flocculant provides a sustainable alternative to existing industrial wastewater treatment processes

Efficient adsorption of fluorescein dye from aqueous solutions by Al/Th-MOF bimetal-organic frameworks: Adsorption isotherm, kinetics, DFT computation, and optimization via Box-Behnken design

Bimetal-organic frameworks, or MOFs, have sparked a lot of interest in the wastewater treatment industry. This study investigated the possibility of removing fluorescein dye (FS) employing bimetal-organic frameworks based on aluminum and thorium (Al/Th-MOF) from aqueous solutions. To investigate the properties of the material further, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, surface charge analysis, and X-ray diffraction (XRD) were used. Using these methods, we were able to identify the Al/Th-MOF's point of zero charge. Following adsorption, the adsorbent's large surface area of 2273.8 m2/g and pore volume of 1.4 cm3/g drop to 1678.9 m2/g and 0.96 cm3/g, individually. As this suggests, it is ideal that a portion of the FS was absorbed within the pores of the adsorbent. Through batch testing, it looked into the connection between adsorption equilibrium and pH levels, and found that changes in solution pH significantly affected adsorption behavior. Further studies with kinetic models led to the discovery of the pseudo-second-order model for FS adsorption on Al/Th-MOF. Furthermore, the Langmuir isotherm model accurately describes the adsorption process, suggesting that chemisorption played a major role in the process as a whole. To optimize factors such adsorbent dosage, time, solution pH, the response surface methodology (RSM) and Box-Behnken design (BBD) were used. As a consequence (ΔH°), (ΔS°), and (ΔG°) data the adsorption of FS employing Al/Th-MOF as an adsorbent is endothermic and spontaneous. Our study's studies have demonstrated that the Al/Th-MOF adsorbent combines a number of mechanisms, such as π-π interaction, H-bonding, pore filling, and electrostatic contact, to effectively remove FS dye from water-based solutions. The adsorption capacity of FS onto Al/Th-MOF reaches a maximum of 668.6 mg.g−1 at a pH value of 4, demonstrating that the adsorbent is particularly successful in removing FS from wastewater samples. Furthermore, the synthesized Al/Th-MOF adsorbent possesses outstanding render ability and cyclability for a maximum of eight adsorption-desorption cycles, suggesting that it could find application as an adsorbent in industrial environments. Overall, our research suggests that the adsorbent is a potential and novel approach for managing industrial effluent and water filtering.

Wastewater Treatment of Food Industry Using Electrochemically Generated Ferrates

The article considers a complex technology for electrochemical wastewater treatment from a meat processing plant. The process of water treatment includes a sequential processing in graphite and iron anode-based electrochemical modules, and exposure in maturation and homogenization chamber. Ferrate generation has been evidenced in the iron anode-based module, and ferrates concurrently acting as mild oxidants, coagulants, and steel corrosion inhibitors. The electrochemical potential of ferrates ranges from 1.3 to 1.5 V in aqueous solutions for the pH values between 6 and 8. Provided an increase in ferrate concentration up to 20 mg/L in the solution, the corrosion rate for capacitive equipment and pipelines is reduced by twofold. An application of iron (III) hydroxide as a product of ferrate reduction lowers wastewater clarification by 1.5-2.0 times compared to the widely used ferric iron and aluminum salts. The research findings provide for the advancement of integrated water treatment solutions and highlight the importance of implementing efficient treatment processes to minimize the environmental impact of meat processing plants.

Photo-Fenton like catalyst system with CuCOFe2O4@AC nanoparticles for ciprofloxacin removal from aqueous solutions and effluent toxicity assessment by Escherichia coli and Enterococcus faecalis bacteria

In this study, the removal of the antibiotic ciprofloxacin (CIP) from aqueous solutions was investigated using the Photo-Fenton like (PFL) process and CuCOFe2O4@AC (CAC) magnetic nanoparticles as catalysts. First, CAC nanoparticles were synthesized and their characteristics were determined by XRD, VSM and FESEM, EDS, Mapping, FTIR. The removal efficiency of CIP in each of the nanomaterial processes, including UV, H2O2, CAC, UV+H2O2, CAC+H2O2 (Fenton like), and UV+CAC+H2O2 (PFL), were 1.0%, 7.97%, 61.37%, 6.0%, 73%, and 84%, respectively. Therefore, the PFL process was optimized as a suitable process, and the optimal conditions were determined as follows: H2O2 concentration of 2500 mg/L, pH of five, CAC dose of 600 mg/L, CIP concentration of 15 mg/L, and contact time of 50 min. The removal efficiency of CIP was achieved at 95.99%. The kinetic studies on the PFL process for the removal of CIP shown that the first order kinetic model exhibits better compatibility with the obtained results compared to other investigated kinetic models. Furthermore, the synergistic effect of the PFL process was equivalent to 1.8 times the individual processes. The results of microbiological tests in treated wastewater samples and control sample indicate the non-toxicity of residual pharmaceuticals wastewater on E. coli and E. faecalis bacteria. Due to the non-toxicity of the wastewater and the ability to recover nanoparticles using magnetism, as well as the possibility of recycling the nanoparticles, this technique can be effectively used as a suitable process in pharmaceutical industry wastewater treatment.

Stability optimization of iron-based catalysts: Application of Cr-enriched alloy steel catalyst in ozonation pharmaceutical wastewater

Catalytic ozonation for advanced treatment of industrial wastewater has proved to be effective, and the stability of the catalyst is crucial for the long-term application of the ozonation process in practical engineering. In this study, the electrochemical characteristics of four iron (Fe) shavings: alloy steels (38CrMoAl and 40Cr) and carbon steels (A3 and 45#) were investigated, and a new citric acid-optimized H2O2 modification method was proposed. The low open circuit potential (OCP) of carbon steels indicated that they were more likely to be oxidized therefore required shorter modification times. The higher the OCP of alloy steels, the higher H2O2 concentration was required to enhance modification efficiency. By adding citric acid, the rapid modification of alloy steel was achieved, and the catalysts exhibited lower passivation current (Ip), indicating a lower rate of substrate loss and a longer lifetime of alloy steel catalysts. Furthermore, chromium (Cr) enrichment occurred in the oxide layer of alloy steel catalysts. The Cr/Fe (atomic ratio) in oxide layer for 38CrMoAl and 40Cr increased from 0.018 to 0.040 and from 0.010 to 0.037, respectively. The presence of CrOOH and Cr2O3 within the oxide layer reinforced the layer’s overall structural integrity and enhanced its protection for the internal substrate, making the catalysts more resistant to adapt to high-salinity wastewater. Through laboratory tests, it was found that among the four catalysts, 38CrMoAl showed the highest stability and good catalytic activity with low Fe loss concentration. Therefore, the pilot-scale application effect of 38CrMoAl catalyst was evaluated. In the advanced treatment of pharmaceutical wastewater, chemical oxygen demand (COD) and total organic carbon (TOC) removals were 56.3% and 32.4%, respectively. These results showed that the stability of catalyst can be improved by optimizing the selection of steel, and the introduction of citric acid achieved Cr enrichment effect and amplified the potential stability advantage of alloy steel. The research provides guidance on raw material selection for catalyst preparation to different industries' wastewater treatment, especially in high-salinity wastewater ozonation treatment, which can realize the long-term stable application of catalyst.

Comparative study of microwave-assisted and hydrothermal hydroxyapatite synthesis from neutralization slag: Optimization, energy, and adsorption

The study proposes the utilization of microwave-assisted methods for converting neutralization slag (NS) into hydroxyapatite (HAP), offering an alternative to the conventional hydrothermal method. The microwave-assisted approach addresses the challenges encountered in hydrothermal reactions, such as particle agglomeration, reduced specific surface area, prolonged reaction time, high temperature requirements, and inadequate saturation adsorption capacity. By employing the response surface methodology with a Box-Behnken design, the study found that the microwave-assisted method significantly reduced the synthesis time from 90 to 25 min and the temperature from 120 °C to 56 °C. Furthermore, the microwave method consumed only 1/43 of the energy utilized in hydrothermal synthesis. To assess the performance of the synthesized HAP, various detection methods were utilized, including XRD, SEM-EDS, FTIR, Zeta potential, and ICP, which analyzed the crystal structure, crystallinity, morphology, chemical composition, and surface charge of HAP. The BET method was used to measure the specific surface area, further confirming the successful synthesis of HAP. The HAP synthesized through this microwave-assisted method exhibited a saturation adsorption capacity of up to 98.4 mg/g of fluoride ions from vanadium industrial raffinate. This study demonstrates that the microwave-assisted method provides a viable solution for reducing energy consumption and enhancing HAP synthesis efficiency for wastewater treatment in the vanadium industry.

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.

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.