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The discharge of untreated electroplating wastewater could lead to the formation of toxic metal-organic complexes that is harmful for the environment. There are several processes reported to treat electroplating wastewater such as chemical precipitation, adsorption, coagulation and flocculation, ion exchange, electrocoagulation, membrane filtration, advanced oxidation process and biorecovery. These methods provide the possibility to capture different toxic metals and remove organic pollutants. The combination of different processes together has shown higher efficiencies in removing a wide range of contaminants than single treatment systems. The main challenge is identifying the highest treatment performance and most cost-efficient process. This review provides an overview of treatment technologies for electroplating wastewater and describes the strengths and drawbacks among them. The efficiency of different systems and kinds of pollutants removed, along with a comparison between these systems have been analysed. When comparing the treatment technologies, it is hard to identify the most efficient one as each method has been successful in removing certain pollutants that has not been recovered from the other methods. Therefore, making the decision on identifying the best treatment technology depends on the objective of the treatment and the targeted pollutants. Furthermore, the cost of different technologies has been evaluated based on literature to have a brief look at cost differences between the technologies. When targeting removal of heavy metals, the highest cost of treatment has been reported at around 4.45 $/m3 for the adsorption method employing nano zero valent iron (nZVI). While the lowest cost of treatment has been reported at about 0.35 USD/m3 employing an adsorption method followed by electrodeposition. [ABSTRACT FROM AUTHOR]

In response to Egypt's escalating water scarcity and pollution, Riverbank Filtration (RBF) technology is emerging as an effective solution to enhance water quality and simplify drinking water provision. This study evaluates RBF at three sites in Upper Egypt by assessing hydrogeological conditions and water quality based on 36 parameters from 2022 to 2023. Findings indicate that RBF efficiently treats infiltrated river water, with all sites meeting turbidity and microbiological standards (Total Bacterial Count and Coliforms), achieving removal rates of approximately 90% and 99%, respectively. Despite these successes, challenges persist in reducing manganese to safe levels, with concentrations at Alsaayda site reaching 0.51 mg/L, over the drinking water safe limit of 0.4 mg/L. To address this, further post-treatment strategies are proposed to remove the excess manganese. A practical application of an Oxidizer at the Bani Murr groundwater treatment plant has demonstrated the effective removal of iron and manganese, bringing their levels down to safe drinking water standards. This case exemplifies a successful solution for iron and manganese removal. This research highlights RBF's potential in water treatment in developing countries, while emphasizing the need for supplementary measures to manage specific contaminants. [ABSTRACT FROM AUTHOR]

Waterlogging and soil salinity issues can be handled using surface or subsurface drainage networks, soil bed elevation, and soil and crop management patterns. A properly operating and maintained drainage system is important for both rural and urban inhabitants to protect lives and property from flooding and high groundwater levels, enhance health conditions, and safeguards water purity, soil salinity, and waterlogging. It also supports and increases crop yields and consequently rural incomes. This study assessed the maintenance condition of the main surface drains (Baloza and ELFarama) located in the Tina Plain (50,000 acres) and a portion of the Southeast El-Kantara regions (25,000 acres) in North Sinai, Egypt, based on the values of the Discharge Capacity Ratio (DCR) and Manning's roughness (n). Ten measurement locations at the drain cross-section were used in the investigation. For the ELFarama Drain, the average values of n and DCR were found to be 0.029 and 86.2%, and for the Baloza Drain, they were 0.032 and 78.6%, respectively. Compared to the design values, the actual Manning's roughness was higher, indicating that the drainage canals' capacities had been reduced and that their upkeep was inadequate. In both drains, sedimentation is present and they need to be maintained, according to the hydrographic surveying results for the actual cross-sections compared to the planned cross-sections. A methodology for the channel maintenance method is presented. For removing vegetation and dredging sediment, a long-boom mechanical hydraulic excavator with a bucket is suggested and to be conducted every two years. To the results of this study, the amount of weed infestation in vegetated channels is the main factor that affects Manning's roughness coefficient value. It is now easier to calculate the proportion of weeds that are submerged in vegetated channels using echo-sound sonar technology. The DCR is an affordable and simple methodology to assess the channel maintenance status for sustainable agriculture. [ABSTRACT FROM AUTHOR]

This study investigates the impact of the COVID-19 pandemic and the Ever Given ship blockage on the air quality in Suez Canal region. Nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), and aerosol optical depth (AOD) were studied, and data were obtained from satellite instruments. The study compared monthly average data for 2020, 2021, and 2022 with a baseline period of 2017–2019 to investigate the pandemic's effect. The study also analyzed the corresponding period of the canal blockage to identify its impact on air pollution levels. The pandemic had a significant role in decreasing NO2 by 2.5 × 1014 molecule/cm2 and SO2 by 0.05 DU due to reduced car traffic and industrial activities. A reduction in AOD by 20% and CO concentration in the range from 3.5% to 4.7% was reported in early 2020. During the blockage, NO2 and SO2 levels decreased by 14.4% and 66.0%, respectively, while CO and AOD index increased by 12.68% and 51.0%, respectively. The study concludes that the containment measures during the pandemic had a positive impact on the environment, which shows how the reduction in the anthropogenic activities, especially industrial and transportation activities, have improved the air quality. Thus, stricter actions are needed to protect the environment; for example, the transition towards the using of electric vehicle is necessary, which is part of Egypt's strategy to transition towards a green economy. The government should also adopt a policy to trade carbon emissions reduction certificates to help reduce air pollution. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the removal efficiency of heptachlor from aqueous solutions using bimetallic iron/copper (Fe/Cu) nanoparticles. The highest removal efficiency of 99.3% for heptachlor compounds was achieved at pH 7.0, bimetallic Fe/Cu dosage 0.33 g/L, initial heptachlor concentration 2 µg/L, contact time 30 min, and stirring rate 250 rpm. The adsorption data of heptachlor fitted well to Koble–Corrigan isotherm and Avrami kinetic model. Artificial neural network r2: 0.9567) was more precise than the response surface methodology (r2: 0.774) in simulating the adsorption of heptachlor onto the bimetallic Fe/Cu nanoparticles. This study indicated that bimetallic Fe/Cu could be employed as an efficient adsorbent for the removal of heptachlor compound. [ABSTRACT FROM AUTHOR]

This study investigated the adsorption of PO43− onto encapsulated nanoscale zero-valent iron (nZVI). At initial PO43-: 10 mg · L−1, the optimum condition was initial pH: 6.5, nZVI dosage: 20 g · L−1, stirring-rate: 100 rpm, and time: 30 min, achieving PO43− removal of 42%. The effect of pH and time on the PO43− removal efficiency was quadratic-linear concave up, whereas the curve of nZVI dosage was quadratic-convex. Artificial neural network with a structure of 5−7−1 adequately predicted PO43− removal (R2: 97.6%), and the sensitivity analysis demonstrated that pH was the most influential input. The cost of the adsorption unit was 3.15 $USD · m−3. [ABSTRACT FROM AUTHOR]

Pollution prevention (P2) assessment was conducted by applying the three R’s, reduce, reuse, and recycle, in a chemical industry for the purpose of reducing the amount of wastewater generated, reusing paint wastewater in the manufacture of cement bricks, recycling cooling water, and improving water usage efficiency. The results of this study showed that the annual wastewater flow generated from the paint manufacturing can be reduced from 1,100 m3to 488.4 m3(44.4% reduction) when a high-pressure hose is used. Two mixtures were prepared. The first mixture (A) contains cement, coarse aggregate, fine aggregate, Addicrete BVF, and clean water. The second mixture (B) contains the same components used in the first mixture, except that paint wastewater was used instead of the clean water. The prepared samples were tested for water absorption, toxicity, reactivity, compressive strength, ignitability, and corrosion. The tests results indicated that using paint wastewater in the manufacture of the cement bricks improved the mechanical properties of the bricks. The toxicity test results showed that the metals concentration in the bricks did not exceed the U.S. EPA limits. This company achieved the goal of zero liquid discharge (ZLD), especially after recycling 2,800 m3of cooling water. The total annual saving could reach $42,570 with a payback period of 41 days. Implications: This research focused on improving the water usage efficiency, reducing the quantity of wastewater generated, and potentially reusing wastewater in the manufacture of cement bricks. Reusing paint wastewater in the manufacture of the bricks prevents the hazardous pollutants in the wastewater (calcium carbonate, styrene acrylic resins, colored pigments, and titanium dioxide) from entering and polluting the surface water and the environment. We think that this paper will help to find the most efficient and cost-effective way to manage paint wastewater and conserve fresh water resources. We also believe that this paper provides a rich agenda for future research in water conservation and industrial wastewater reuse subjects. [ABSTRACT FROM AUTHOR]