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Access to safe drinking water is a pressing global concern, necessitating innovative purification methods. This study investigated the efficacy of combining calcination-modified zeolite filtration with ultraviolet (UV) disinfection to mitigate microbial contamination in raw groundwater. A comparison was made between the treatment system employing calcination-modified natural zeolite and the system utilizing natural zeolite without modification. Results from isotherm and kinetic modeling revealed enhanced adsorption behavior and mechanisms in modified zeolite compared to its natural counterpart, leading to improved adsorption capacity and kinetics. Enhancements in removal efficiencies were observed for contaminants such as zinc, cadmium, and manganese, with increases from 30.25 % to 67.5 %, 55.75 %–82.75 %, and 64.04 %–69.52 %, respectively. Similarly, enhanced removal efficiencies for organic contaminants like phenol and cyanides were noted, rising from 59.99 % to 73.26 % and 59.22 %–65.05 %, respectively, with the modified zeolite. Furthermore, filtration with both natural and modified zeolites coupled with UV disinfection substantially reduced microbial contamination levels in raw groundwater, with total coliforms decreasing from 2245 CFU/mL to 8 CFU/mL post-filtration and UV treatment. Notably, surface area increased from 60 m2/g to 220 m2/g, and pore volume increased from 0.15 cm³/g to 0.8 cm³/g for modified zeolite. These findings underscore the potent antimicrobial efficacy and improved adsorption performance of the combined approach, contributing to advancing water purification technologies and addressing critical global health challenges.

Metal plating industries generate wastewater containing heavy metals, necessitating effective treatment methods to mitigate environmental contamination. This study investigated the potential of banana peel-derived activated carbon (BPAC) and commercial activated carbon for heavy metal removal, addressing a pressing environmental concern. The analysis encompassed diverse pH levels, crucial for real-world applicability, offering valuable insights into adsorption capacities and kinetics. The results revealed competitive performance of both materials, with typical lead (Pb) removal ranging from 4 to 6 mg/g and cadmium (Cd) from 3 to 5 mg/g. Commercial activated carbon exhibited slightly superior adsorption kinetics and capacities, highlighting its efficacy in heavy metal removal. Throughout the study, optimizing dosage proved essential for maximizing removal efficiency, emphasizing the practical implications of this research. Furthermore, the time-dependent behavior of adsorption kinetics underscored the importance of extended contact times for enhanced removal. Generally, BPAC emerged as a promising solution for heavy metal removal from industrial wastewater. It consistently achieved removal efficiencies typically ranging from 75 % to more than 90 %, making it a viable alternative in the realm of wastewater treatment. At pH 4, BPAC demonstrated significantly higher adsorption capacity, with lead (Pb) at 5.50 ± 0.20 (mg/g) and cadmium (Cd) at 4.10 ± 0.15 (mg/g), compared to slightly lower values for commercial activated carbon, Pb at 5.20 ± 0.25 (mg/g) and Cd at 3.90 ± 0.20 (mg/g). This study contributes significantly to wastewater treatment methodologies, offering sustainable and efficient approaches to address heavy metal contamination in industrial effluents.

The research investigated the adsorption capacity of graphene oxide nanosheets towards non-steroidal anti-inflammatory drugs (NSAIDs) across diverse experimental conditions. Batch adsorption experiments indicated a correlation between higher pH levels, elevated temperatures, and increased adsorption capacity, affirming theoretical expectations. Kinetic analysis revealed pseudo-second-order kinetics predominance, suggesting chemisorption as the rate-limiting step. Moreover, the rate constant (k1) declined with rising pH and temperature, implying a potential impact on reaction kinetics and optimization strategies. For instance, at pH 7 and 30 °C for 4 hours, the adsorption capacity was higher than expected compared to conditions at pH 6 and 25 °C for 2 hours, despite the lower initial concentration of the target substance. The pseudo-second-order kinetics model illuminated the nuanced relationship between pH, temperature, and adsorption rate, emphasizing environmental sensitivity and surface chemistry alterations. Equilibrium adsorption studies employing Langmuir and Freundlich isotherm models underscored monolayer adsorption and revealed varying adsorption capacities and affinities under different conditions. For example, at pH 6 and 25 °C for 2 hours, the maximum adsorption capacity (qmax) was found to be 24.9 mg/g ± 4.2, with a Langmuir adsorption constant (KL) of 0.058 L/mg ± 0.011. The diffusion behaviour within adsorbent particles, assessed via the intra-particle diffusion model, indicated both rapid and progressively slower diffusion with increasing pH and temperature. The findings collectively underscore the complexity of adsorption dynamics, urging comprehensive consideration of pH, temperature, and intra-particle diffusion for optimizing adsorption processes. This research enhances the understanding of graphene oxide nanosheets' adsorption behaviour towards NSAIDs, offering valuable insights for environmental remediation and optimization strategies.

The alarming rise of pharmaceutical contaminants in wastewater poses a significant environmental and public health challenge. Addressing this issue, this study investigated the potential of alkaline-treated pineapple leaf fiber (PALF) as an eco-friendly adsorbent for pharmaceutical removal, coupled with UV-LED technology. Alkaline treatment enhanced PALF's adsorption capabilities, increasing surface area to 68.3 m2/g and pore volume to 0.120 cm³/g. Adsorption experiments showed high efficiencies (up to 89.7 % for ciprofloxacin, 88.5 % for paracetamol, and 77.1 % for ibuprofen), following a pseudo-second-order kinetic model. Isotherm analysis indicated a maximum adsorption capacity of 35.4 mg/g for ciprofloxacin. PALF maintained 85.9 % removal efficiency after five regeneration cycles, with no adverse effects on aquatic organisms observed in toxicity assays. This research highlights PALF's promise as a sustainable solution for pharmaceutical wastewater treatment, aligning with the focus on environmental sustainability and innovative materials.

Abstract Innovation management stands as a pivotal driver in attaining enduring sustainability in livelihoods. However, its progress can face formidable obstacles, encompassing the complexities arising from human perceptions. This research delved into the realm of innovation management within the context of fruit and vegetable preservation, with a keen focus on the potential impact of the COVID-19 pandemic and the perceptual evaluations surrounding the viability of utilizing ultraviolet (UV) irradiation for this purpose. The perceived effectiveness of UV irradiation in fruit and vegetable preservation was found to be significantly influenced by factors, such as cost, safety, and limited understanding. The respondents' preference for preserved fruits and vegetables was most significantly influenced by the elimination of pathogenic microorganisms, as indicated by a mean score of 4.6. Notably, around 50.9% of the participants demonstrated a lack of understanding regarding the use of ultraviolet irradiation as a preservation technology. In addition, approximately 21.6% of the respondents expressed disinterest in adopting ultraviolet irradiation for preserving fruits and vegetables. In contrast, a smaller percentage of participants, merely 12.3%, showed a positive inclination towards employing ultraviolet irradiation in the preservation process. Interestingly, approximately 15.2% of respondents remained undecided and did not express a definitive preference concerning their willingness to utilize ultraviolet irradiation for preserving fruits and vegetables. Notably, the analysis has revealed a compelling trend, with a substantial portion of participants (63%) perceiving medium-sized enterprises involved in fruit and vegetable processing technologies as displaying notably low levels of motivation for innovation during the COVID-19 era. A similar viewpoint was shared by 51% of respondents regarding large-scale businesses. In stark contrast, the survey has illuminated a striking disparity, as small-scale businesses exhibited significantly heightened innovation motivation at 28%, surpassing the modest 10% observed in both medium-sized and large-scale counterparts. This pronounced variation in innovation motivation across diverse business scales highlights the multifaceted impact of the pandemic on their inclination towards embracing innovation. These findings offer invaluable insights into the intricacies governing innovation management within the fruit and vegetable preservation sector amidst the challenging COVID-19 period.

This study explored the effectiveness of integrating Microbial Fuel Cells (MFC) with Metal-Organic Frameworks (MOF) enhanced by graphene oxide as a unique approach for carwash effluent treatment. The research encompassed three key components: analyzing MFC in isolation, evaluating MOF alone, and studying the combined MFC and MOF approach. The results demonstrated that the simultaneous use of MOF and MFC led to significant improvements in pollutant removal, indicating a synergistic effect on various pollutants within the wastewater. In retrospect, the MFC displayed low power density (0.095 mW/m2) and current density (2.8 mA/m2) during the initial 2 hours. However, a significant increase occurred, peaking at 46.2 mA/m2 and 21.62 mW/m2 by the 18th hour. Although current density decreased thereafter, power density stayed relatively high, indicating stabilization of microbial activity. The 48-h experiment concluded with 17.4 mA/m2 and 11.28 mW/m2. Notably, the combined MOF and MFC treatment consistently outperformed individual treatments, especially in the removal of heavy metals like zinc, nickel, and cadmium, with zinc removal rates increasing from 92.6 % to 96.5 %. In terms of organic contaminants, the integrated treatment approach achieved a remarkable 99.2 % removal of Biochemical Oxygen Demand (BOD). Moreover, the integrated treatment approach achieved a remarkable 100 % removal efficiency for turbidity and TSS, resulting in improved water clarity due to better fine suspended particle removal facilitated by MFC. The findings suggest that the combination of MOF and MFC holds great potential for comprehensive wastewater treatment, effectively eliminating a range of contaminants, including organic compounds, heavy metals, and general water quality parameters. The practical application of this integrated method can be further optimized and expanded through additional research and system refinement.

The management of wastewater from carwash centers continues to pose a significant global challenge, with the quest for treatment methods that are both effective and economical proving particularly daunting. This underscores the importance of exploring natural materials for wastewater treatment. However, knowledge regarding the efficacy of bio-functionalized wheat straw and pistachio shells specifically for carwash wastewater treatment remains limited. This study explored the potential of wastewater treatment using bio-functionalized agricultural waste materials, specifically wheat straw and pistachio shells. Experimental setups included treatment plants using wheat straw alone, pistachio shell alone, a mixture of both, and a series connection. Removal efficiencies across various water quality parameters revealed the series connection as the most effective treatment, achieving exceptional removal efficiencies for critical parameters such as fat, oil, and grease, total suspended solids, and turbidity. The Mixture treatment demonstrated synergistic effects, surpassing individual treatments in removing contaminants such as Arsenic, Biochemical Oxygen Demand, cadmium, Chemical Oxygen Demand, fluorides, ammonia nitrogen, and surfactants. More precisely, the series treatment setup resulted in nearly complete removal efficiency, approximately 100%, for Fat, Oil, and Grease, turbidity, and total suspended solids in the wastewater samples. The treatment setup using only wheat straw achieved removal efficiencies between 41.3% and 83.3%, whereas the setup using only pistachio shell achieved removal efficiencies ranging from 43.3% to 89.1%. Statistical analyses confirmed the significance of observed differences, with isotherm and kinetic models providing valuable insights into adsorption characteristics. Freundlich constants ranged from 3.6 to 12.38, Moreover, the integrated treatments consistently outperformed individual ones, as demonstrated by Water Quality Index values. The Water Quality Index values ranged from 2114.26 for raw wastewater, classified as “unsuitable for drinking,” to 154.47 for the series connection of wheat straw and pistachio shell, indicating a significant improvement in water quality.

Agricultural waste holds promise as an adsorbent in wastewater treatment; however, its potential remains understudied, particularly regarding biofunctionalized grape pomace, coffee husks, and corn cobs for carwash wastewater treatment, along with their integration with solar-powered UV-LED disinfection. This study explores the effectiveness of these bio-functionalized adsorbents in wastewater treatment, revealing grape pomace's high efficacy in removing lead (95.2%), fluorides (94.4%), and nitrates (94.8%), while corn cobs and coffee husks showed significant removal efficiencies for zinc (88.5% and 95.5%, respectively) and cyanides (84.8% and 89.6%, respectively). Grape pomace exhibited a maximum adsorption capacity (qmax) of 162.6 mg/g for lead ions, while coffee husks had the highest qmax of 182.82 mg/g. Kinetic analysis indicated corn cobs' slower initial adsorption capacity and moderate adsorption rate, contrasting with grape pomace and coffee husks. Furthermore, treatment with these adsorbents, followed by UV-LED disinfection, substantially reduced microbial counts in treated water, underscoring their potential in ensuring water safety. The integration of biofunctionalized adsorbents with UV-LED disinfection presents a promising approach for sustainable and efficient wastewater treatment, with implications for water quality improvement and public health protection.

The pervasive presence and detrimental impact of microplastics in the environment pose a multifaceted and urgent challenge requiring innovative solutions and comprehensive mitigation strategies. This study investigated the efficacy of biofilm-enhanced coconut coir in removing microplastics from wastewater, addressing the pressing issue of microplastic pollution. Through comprehensive experimentation, the adsorption capabilities of coconut coir across various types and sizes of microplastics under different operational conditions were examined. The addition of biofilm significantly enhanced the adsorption capacity of coconut coir, leading to improved microplastic removal efficiencies, with typical specific surface area values increasing from 1000 m2/g to 1200 m2/g and pore volume from 0.5 cm³/g to 0.6 cm³/g with biofilm augmentation. Moreover, the study revealed consistent improvements in microplastic removal efficiency across different types and sizes of microplastics with biofilm presence, ranging from 85 % to 95 %, compared to removal efficiencies varying from 72 % to 82 % without biofilm enhancement. Langmuir analysis revealed that coconut coir exhibited favorable adsorption of microplastics, with and without biofilm, demonstrating high correlations between observed and predicted values (R2 = 0.999). These findings underscore the potential of biofilm-enhanced coconut coir as a promising solution for mitigating microplastic pollution in aquatic environments.

In today's age, finding harmony between construction endeavors and safeguarding the environment is of utmost importance. Consequently, there is a substantial requirement to explore the feasibility of utilizing waste materials as a replacement for traditional construction substances. Unfortunately, there is a lack of information regarding the possibilities of incorporating recycled glass, rice husk, and sugarcane bagasse ash into concrete production. This study investigated the viability of integrating recycled glass fibres and agricultural waste ash into concrete to bolster its strength and sustainability. When evaluating mechanical and durability properties across five mixtures, the concrete formulations ranged in fibre content percentages from 1% to 3% and in ash content percentages from 10% to 20%. Specifically, Mixtures 1, 2, 3, 4, and 5 contained 1% fibre and 10% ash, 2% fibre and 15% ash, 2.5% fibre and 20% ash, 3% fibre and 12% ash, and 1.5% fibre and 18% ash respectively. Mixture 2 and Mixture 5, boasting heightened fibre and ash content, showcased outstanding compressive strength at 38.5 MPa and 37.2 MPa, respectively, indicating a positive correlation between these materials and concrete strength. Conversely, Mixture 3, burdened with excessive fibre and ash content, witnessed diminished strength, underscoring the necessity for meticulous optimization. In terms of tensile and flexural strength, Mixture 2 and Mixture 5 displayed commendable performance, while Mixture 3 suffered setbacks from excessive content. Durability assessments unveiled Mixture 1 and Mixture 4's superior freeze-thaw resistance, with minimal mass loss (1.5% and 1.8%, respectively) and no visible damage, rendering them favorable choices for sustainable construction. Contrastingly, Mixture 3 exhibited poorer freeze-thaw resistance and higher environmental impact, highlighting the need for careful consideration in material selection. Overall, this study underscores the importance of optimizing concrete formulations through the integration of recycled materials, paving the way for stronger, more durable, and environmentally friendly construction practices.

The issue of carwash wastewater emerges as a pressing environmental concern on a global scale, primarily due to the intricate nature of its pollutants, which makes effective treatment a formidable challenge. In the face of this complex scenario, the pursuit of an efficient treatment methodology assumes paramount importance. In response to this complex scenario, this study embarked on an exploration of a novel polymeric adsorbent material synthesized from Zeolitic Imidazolate Framework-67, Zeolitic Imidazolate Framework-8, Polyethersulfone, and graphene oxide in a fixed-bed treatment system for carwash wastewater. The investigation encompassed three distinct filter column depths, measuring 8 cm, 12 cm, and 16 cm, respectively. With an increase in filter depth from 8 cm to 16 cm, notable improvements were observed in the removal efficiencies for most contaminants. Notably, oils/grease removal showed an increasing trend with column depth, reaching 95.4%, 98.6%, and 100% for 8 cm, 12 cm, and 16 cm depths, respectively. TSS and Turbidity removal efficiencies remained consistently high at 100% across all depths, showcasing effective removal of solid particulate matter. Copper and Zinc removal efficiencies increased with deeper column depths, reaching values of 80.4%–89.9% and 79.6%–90.3%, respectively. Surfactants exhibited efficient removal, with values ranging from 90.6% to 96.6%. Total Dissolved Solids removal efficiency increased from 71.6% to 83.4% as column depth increased. Similarly, Chemical Oxygen Demand, Biochemical Oxygen Demand, total organic carbon, and phosphates removal efficiencies showed improvement with increasing column depth, reaching values of 95.4%, 98.3%, 98.8%, and 89.3%, respectively. Moreover, The composite MOF beads demonstrated significant adsorption capacities in carwash wastewater treatment, with a noteworthy 35.08 mg/g for Oils/Grease and 28.12 mg/g for Biochemical Oxygen Demand, highlighting their efficiency in removing hydrophobic contaminants and organic pollutants.The derived results highlight the potential of the composite material for carwash wastewater treatment towards advancing the field of wastewater treatment.

Efficient sanitation system management relies on vigilant sewage surveillance to uphold environmental hygiene. The absence of robust monitoring infrastructure jeopardizes unimpeded conduit flow, leading to floods and contamination. The accumulation of harmful gases in sewer chambers, coupled with tampered lids, compounds sewer network challenges, resulting in structural damage, disruptions, and safety risks from accidents and gas inhalation. Notably, even vehicular transit is vulnerable, facing collisions due to inadequately secured manholes. The core objective of this research was to deconstruct and synthesize a prototype blueprint for a live-feed sewer monitoring framework (LSMF). This involves creating a data gathering nexus (DGN) and empirically assessing diverse wireless sensing implements (WSI) for precision. Simultaneously, a geographic information matrix (GIM) was developed with algorithms to detect sewer surges, blockages, and missing manhole covers. Three scrutinized sensors—the LiDar TF-Luna, laser TOF400 VL53L1X, and ultrasonic JSN-SR04T—were evaluated for their ability to measure water levels in sewer vaults. The results showed that the TF-Luna LiDar sensor performed favorably within the 1.0–5.0 m range, with a standard deviation of 0.44–1.15. The TOF400 laser sensor ranked second, with a more variable standard deviation of up to 104 as obstacle distance increased. In contrast, the JSN-SR04T ultrasonic sensor exhibited lower standard deviation but lacked consistency, maintaining readings of 0.22–0.23 m within the 2.0–5.0 m span. The insights from this study provide valuable guidance for sustainable solutions to sewer surveillance challenges. Moreover, employing a logarithmic function, TF-Luna Benewake exhibited reliability at approximately 84.5%, while TOF400 VL53L1X adopted an exponential equation, boasting reliability approaching approximately 89.6%. With this navigational tool, TF-Luna Benewake maintained accuracy within ±10 cm for distances ranging from 8 to 10 m, showcasing its exceptional performance.

Groundwater salinity is a crucial factor that can impact soil structure and plant water uptake, potentially posing a threat to agricultural productivity. This study focused on assessing the salinity hazard of groundwater in low-lying coastal zones, specifically in Dar es Salaam. Thirty four boreholes were examined, and six water quality parameters (magnesium, calcium, sodium, potassium, total dissolved solids and electrical conductivity) were analyzed to investigate the feasibility of using groundwater for irrigation. Sodium adsorption ratio indices were calculated and employed to construct the Wilcox diagram, which played a crucial role in determining the groundwater suitability for irrigation. The concentrations obtained from the analysis of water quality parameters were compared to the permissible limits recommended by the Food and Agriculture Organization of the United Nations. Based on the Sodium Adsorption Ratio analysis, 14.7% of the examined samples were assigned to class one (S1), indicating irrigation-worthy water quality with minimal risk of harmful salt accumulation in the soil. On the other hand, 32.4% of the samples were categorized as class two (S2), indicating water suitable for irrigation with a significant risk that can be effectively managed. Additionally, 17.6% of the sampling points were classified as class three (S3), signifying water unsuitable for most crops. Lastly, 35.3% of the samples fell into class four (S4), suggesting water quality generally unsuitable for irrigation purposes. The analysis indicated that 94% of the samples exceeded 2250 µs/cm, classifying them as C4, indicating extremely high salinity levels rendering them unsuitable for irrigation. This study underscores the importance of conducting comprehensive research before utilizing groundwater for irrigation in low-lying coastal zones.

A fast reduction of a reservoir level may result in instability of an earth dam caused by the high pore water pressures that remain relatively high in the embankment. Moreover, the dissipation of the accumulated pore water pressures is highly dependent on the permeability of the materials used for the embankment and the storage characteristics of the reservoir. Therefore, in the design of embankment dams, the stability analysis under rapid drawdown loading conditions is an important design case. In this study, the influence of different permeability rates on dam stability under different cases of rapid drawdownwas investigated using the finite element method in SEEP/W and SLOPE/W of the GeoStudio with a case of the Lugoda dam in Ndembera catchment, Tanzania. The modeling process considers the time-dependent hydraulic conditions and the transient flow conditions using different water levels during rapid drawdown for evaluation of the factor of safety. From the 1m per day drawdown rate; the lowest minimum factor of safety value (0.90) was obtained from the 10 -7 m/s material permeability of the upstream zone of the dam. It means that, at a drawdown rate of 1m per day, there is a potential for failure of the embankment if the hydraulic conductivity value will be somewhere below 10 -6 m/s.

The study examined the intricate relationships between embankment slope configurations, toe drain designs, and drawdown scenarios. It utilized a unique combination of numerical, physical, and mathematical models. The investigation involved 16 numerical models and 8 physical models with distinct characteristics. The research explored the correlations of key parameters: matric suction, horizontal water conductivity, time, and factor of safety. The factor of safety values varied from 0.62 to 1.03 as a result of the different investigated combinations. For instance, a 1:2 embankment slope without a toe drain under instantaneous drawdown led to the factor of safety values ranging from 1.22 to 1.57. Additionally, incorporating elements like a 30 m toe drain and a 1 m per day drawdown rate influenced these values, with extremes recorded from 1.337 to 2.21, shedding light on embankment stability under diverse conditions and configurations. When subjected to a 1 m per day drawdown, water flow rates decreased significantly at the upstream face and increased downstream, accompanied by an increase in water mass flux at the upstream face and a decrease at the downstream toe, suggesting dynamic changes in water behavior in response to drawdown. Moreover, the findings unveiled significant correlations between matric suction and time (correlation coefficient of 0.950) and factor of safety and water conductivity (correlation coefficient of 0.750). Conversely, a distinct negative correlation emerged between matric suction and factor of safety (correlation coefficient of −0.864). The study’s distinctive insights contribute to our understanding of seepage behavior and dam stability across varied scenarios, offering valuable input for resilient dam construction approaches that will ensure the longevity and effectiveness of these essential structures.

Urbanization is a significant challenge that catchments face around the world leading to difficulty in implementing stormwater-related engineering solutions. This study aimed at investigating the impact of land use/land cover change on hydraulic parameters of a rapidly urbanizing river basin, a case of the Jangwani basin in Dar es Salaam, Tanzania. In this study, the peak discharges were estimated using the SCS-Curve Number Method under the combination of ArcGIS and HEC HMS for three different years (1998, 2009, and 2018). The 100-year rainfall event recorded in 2011 was used to develop the meteorological model in HEC HMS. The steady flow analysis was accomplished using the HEC-RAS software package. To capture the effect of land use/land cover change as well as avoiding variability, the same rainfall dataset was applied for all the three study years. According to the modelling results in HEC RAS, the parameters such as top flow width, average velocity, hydraulic depth, conveyance, shear, stream power as well as the cumulative volume were observed to be increasing with time.

Natural resources are in short supply, and the ecosystem is being damaged as a result of the overuse of fossil fuels. The creation of novel technology is greatly desired for investigating renewable and sustainable energy sources. Microorganisms have received a lot of interest recently for their potential to transform organic waste into sustainable energy and high-value goods. New exoelectrogens that can transmit electrons to electrodes and remove specific wastewater contaminants are expected to be studied. In this study, we examined three distinct samples (as determined by chemical oxygen demand and pH) that can be used as anolytes to generate power in single-chamber and double-chamber microbial fuel cells using graphite electrodes. Wastewater from poultry farms was studied as an exoelectrogenic anolyte for microbial fuel cell power generation. The study examined 10 different bacterial strains, numbered A1 through A10. Due to their highly anticipated capacity to metabolize organic/inorganic chemicals, the diverse range of microorganisms found in poultry wastewater inspired us to investigate the viability of generating electricity using microbial fuel cells. From the investigated bacterial strains, the highest voltage outputs were produced by strains A1 (Lysinibacillus sphaericus) and A2 (Bacillus cereus), respectively, at 402 mV and 350 mV. Among the 10 different bacterial strains, strain A6 generated the least amount of electricity, measuring 35.03 mV. Furthermore, a maximum power density of 16.16 1.02 mW/m2 was achieved by the microbial fuel cell using strain A1, significantly outperforming the microbial fuel cell using a sterile medium. The strain A2 showed significant current and power densities of 35 1.12 mA/m2 and 12.25 1.05 mW/m2, respectively. Moreover, in the two representative strains, chemical oxygen demand removal and Coulombic efficiency were noted. Samples from the effluent anode chamber were taken in order to gauge the effectiveness of chemical oxygen demand removal. Wastewater had an initial chemical oxygen demand content of 350 mg/L on average. Strains A1 and A2 decomposed 94.28% and 91.71%, respectively, of the organic substrate, according to the chemical oxygen demand removal efficiency values after 72 h. Strains A1 and A2 had electron donor oxidation efficiencies for 72 h of 54.1% and 60.67%, respectively. The Coulombic efficiency increased as the chemical oxygen demand decreased, indicating greater microbial electroactivity. With representative strains A1 and A2, Coulombic efficiencies of 10% and 3.5%, respectively, were obtained in the microbial fuel cell. The findings of this study greatly advance the field as a viable source of power technology for alternative energy in the future, which is important given the depletion of natural resources.

Direct utilization of treated effluent from natural treatment systems for irrigation can be challenging on sensitive plants due to high levels of salinity. Post-treatment of such an effluent prior to its applicability in irrigation can be of significant importance. In this study, the wastewater from a natural treatment plant was treated using a lab-scale filtration system with zeolite as a filter material. Three different column depths (0.5 m, 0.75 m, and 1 m) were used to investigate the effect of column depth on the treatment efficiency of the media. The suitability of the raw wastewater and the treated effluent from each column for irrigation purposes was investigated. The water quality parameters investigated were; electrical conductivity (EC), total dissolved solids (TDS), sodium (Na+), calcium (Ca2+), and magnesium (Mg2+). From the analysis results, it was observed that the column depth had a significant influence on the removal efficiency of the pollutants. The highest removal efficiency (94.58%) was achieved from the combination of electrical conductivity and 1 m column depth, while the lowest removal efficiency (10.05%) was observed from the combination of calcium and 0.5 m column depth. The raw wastewater fell mostly into a "very high" hazard, which is class four (C4) based on electrical conductivity and class four (S4) based sodium adsorption ratio; making it unsuitable for irrigation purposes. However, when the wastewater was subjected to 1 m column depth, the quality of the treated effluent improved significantly which in turn also improved the suitability of the effluent for irrigation purposes, with percent compliance ranging from 20.19% to 97.54%.

Groundwater is one of the main sources of water for irrigation used worldwide. However, the application of the resource is threatened by the possibility of high saline levels, especially in low-lying coastal regions. Furthermore, the lack of readily accessible materials for successful treatment procedures makes the purification of such water a constant challenge. Based on the fact that natural zeolite is one of the easily accessible and relatively cheap filter materials, this study examined the potential use of high-salinity groundwater filtered by natural zeolite for irrigation. Zeolite-filled filters at two different depths (0.5 m and 1 m) were studied. The samples were collected from the low-lying areas of Dar es Salaam City, Tanzania. The study observed that when the raw groundwater samples were exposed to the 0.5 m column depth, sodium (Na+) had the lowest removal efficiency at 40.2% and calcium (Ca2+) had the highest removal efficiency at 98.9%. On the other hand, magnesium (Mg2+) had the lowest removal efficiency, at about 61.2%, whereas potassium (K+) had up to about 99.7% removal efficiency from the 1 m column depth treatment system. Additionally, from the salinity hazard potential analysis, most of the samples fell within C4 (based on the electrical conductivity), which is a “very high salinity” class, and based on the quality it means the water cannot be directly applied for irrigation purposes. From the 0.5 m column depth, most of the samples fell within C3 (the “high salinity” class), and from the 1 m column depth most of the samples fell within C1 (“low salinity” class). The findings of this study offer some valuable insight into the prospective use of natural zeolite for the filtration of saline groundwater before its application for irrigation.

Concrete strength gain can be significantly affected by the initial characteristics of the raw materials. Unfortunately, information on the potential influence of the initial water pH on concrete strength gain is still scarce. In this study, the potential effects of the initial water pH on concrete strength gain were investigated using a combination of sensors and a sclerometric test. The impact of initial pH on the strength gain process was investigated using three distinct pH values (4.0, 7.0, and 12). The primary variables examined were pH variations over time, internal temperature, and strength gain. The problem was further examined using a number of statistical techniques, including Single-way Analysis of Variance, Scheffé’s approach, and Correlation Matrixes. When the temperature data from 4.0, 7.0, and 12 pH values were put through the Analysis of Variance, a p-value of 2.4 × 10−261 was retrieved. Additionally, when the strength gain data from 4.0, 7.0, and 12 pH values were subjected to the Analysis of Variance, a p-value of 2.9 × 10−168 was retrieved. The results showed that the differences in the list data retrieved from the investigated pH values were statistically significant. Based on the results, we can state that the initial pH level in the mixing water can have noticeably varied consequences in terms of the strength gain of the concrete and should be carefully considered during the preparation process of concrete. The findings retrieved from this study provide a piece of useful information in the construction field, especially with concrete strength management.

This study investigated the potential influence of operating water levels and loading conditions on the slope stability of an embankment dam. Four different operating reservoir levels (normal, reduced, embankment height, and overflow) were considered in the study. Numerical modeling was used to investigate the problem in the case of the Chardara dam within the Syrdarya catchment in Kazakhstan. Based on the drawdown rates and operating conditions, minimum factor of safety values ranging from 0.56 (total failure) to 2.5 were retrieved. Furthermore, a very high correlation was observed between drawdown days, the minimum factor of safety values, the maximum factor of safety values, and pore-water pressures, with correlation coefficients ranging from 0.561 to 0.997 (strong to very strong correlation). On the other hand, the highest negative correlation of 0.997 was observed between the minimum factor of safety values and pore-water pressures. Additionally, based on the results from the analysis of variance, three reservoir operating levels (normal, embankment height, and overflow) resulted in p-values less than 0.05, indicating that the variations in the factor of safety values from the drawdown rates were statistically significant. The findings of this study demonstrated that, not only may the drawdown rate be detrimental to the embankments, but that different operating levels can also affect slope stability in different ways.

Textile industry production processes generate one of the most highly polluted wastewaters in the world. Unfortunately, the field is also challenged by the availability of relatively cheap and highly effective technologies for wastewater purification. The application of natural zeolite as a depth filter offers an alternative and potential approach for textile wastewater treatment. The performance of a depth filter treatment system can be deeply affected by the column depth and the characteristics of the wastewater to be treated. Regrettably, the information on the potential of these filter materials for the purification of textile wastewater is still scarce. Therefore, this study investigated the potential applicability of natural zeolite in terms of column depth for the treatment of textile wastewater. From the analysis results, it was observed that the filtration efficiencies were relatively low (6.1 to 13.7%) for some parameters such as total dissolved solids, electrical conductivity, chemical oxygen demand, and sodium chloride when the wastewater samples were subjected to the 0.5 m column depth. Relatively high efficiency of 82 and 93.8% was observed from color and total suspended solids, respectively, when the wastewater samples were subjected to the 0.5 m column depth. Generally, the 0.75 m column depth achieved removal efficiencies ranging from 52.3% to 97.5%, whereas the 1 m column depth achieved removal efficiencies ranging from 86.9% to 99.4%. The highest removal efficiency was achieved with a combination of total suspended solids and 1 m column depth (99.4%). In summary, the treatment approach was observed to be highly effective for the removal of total suspended solids, with a 93.8% removal efficiency when the wastewater was subjected to the 0.5 m column depth, 97.5% for 0.75 m column depth, and 99.4% for 1 m column depth. Moreover, up to 218.233 mg of color per g of the filter material was captured. The results derived in this study provide useful information towards the potential applicability of natural zeolite in the textile wastewater treatment field.

Industrial activities produce a variety of pollutants that may not be easily treated using centralized wastewater treatment systems based on a single treatment unit. The variability of the pollutants brings the importance of industrial-specific integrated wastewater treatment plants such as integrated membrane filtration systems. However, the performance of a membrane filtration process can be highly affected by the presence of high amounts of suspended particles in the raw wastewater. Therefore, proper selection of a pre-treatment unit prior to a membrane filtration wastewater treatment system is a key aspect of its performance. This study investigated the performance of an integrated membrane filtration treatment system connected to an electrochemical process (pre-treatment) on the purification of a poultry slaughterhouse wastewater toward achieving a high-quality effluent. The industrial-scale treatment plant installed at the Izhevsk Production Corporative (PC) poultry farm in Kazakhstan is composed of an electrochemical, ultrafiltration (UF), and reverse osmosis (RO) as the main treatment units. From the analysis results, the electrochemical pre-treatment unit was observed to be highly effective for the removal of some physicochemical parameters such as turbidity, color, total suspended solids, total iron, aluminum, chemical oxygen demand, and biochemical oxygen demand; with removal efficiency ranging from 71 to 85%. The low removal efficiency of the pre-treatment system was also observed from free and total chlorine, nitrites, nitrates, phosphates, and ammonium nitrogen; with removal efficiency ranging from 4 to 45%. While in general, the overall treatment train was observed to be highly efficient for some physicochemical parameters such as turbidity, color, total suspended solids, as well as chemical and biochemical oxygen demand; maintaining almost 100% removal efficiency throughout the study period. Also, the high removal efficiency of the electrochemical pre-treatment processes led to a relatively low rate of cake formation on the membrane filters.