Farouk Mezali

In electrocoagulation (EC), coagulants are generated in situ through the corrosion of sacrificial anodes under the application of a direct current (DC) voltage. Simultaneously, electrolytic hydrogen gas (H2) is produced at the cathode. Aluminum and iron are commonly used as anode materials; their dissolution leads to the formation of hydroxides and polymeric hydroxides. These species act as coagulants capable of destabilizing colloidal suspensions and emulsions, as well as adsorbing, neutralizing, or precipitating dissolved pollutants. Ultimately, they form flocs that can be removed by either sedimentation or flotation. In this study, the influence of key operating parameters of EC, such as current density (j), solution pH, and conductivity (κ), was investigated for the removal of a red textile dye. The results show that current density has a significant effect on the removal of turbidity, color, and chemical oxygen demand (COD). Removal efficiencies of 77.25% for turbidity, 86.55% for color, and 78.5% for COD were obtained under the following conditions: initial dye concentration C₀ = 100 mg/L, j = 150 A/m², κ = 3.56 mS/cm, inlet flow rate Q = 0.15 L/min, treatment time t = 40 min, and initial pH = 7.65. Finally, a model relating COD removal to aluminum consumption was proposed, which satisfactorily described the experimental results.

Groundwater recharge is critical for sustainable water management in water-scarce regions like North Algeria, where climate change and urbanization exacerbate resource challenges, particularly in the populous Algiers watershed. This study evaluates groundwater recharge potential using the Analytical Hierarchy Process (AHP) and its fuzzy extension (FAHP), integrated with Geographic Information Systems (GIS), to map recharge zones. Employing open-source data, AHP and FAHP assessed factors such as lithology, slope, and rainfall, classifying the watershed into high, moderate, and low recharge potential zones. Results show AHP identifying 44.01% (528.95 km²) as high, 52.82% (634.93 km²) as moderate, and 3.18% (38.14 km²) as low potential, with FAHP yielding similar outcomes (44.35%, 52.47%, and 3.17%, respectively). Validation using borehole drawdown data confirmed a 73.3% accuracy and an AUC of 0.72, indicating moderate to good reliability. High recharge zones were concentrated in the central and northern areas with permeable soils and gentle slopes, moderate zones dominated the region, and low zones were minimal. This study concludes that both AHP and FAHP are effective for preliminary recharge assessments, with AHP favored for its simplicity, though FAHP excels with uncertain data. Limited high-resolution hydrogeological data highlight the need for further refinement, yet the approach offers a replicable framework for managing groundwater in arid, urbanized regions facing similar environmental pressures.

As a developing country, Algeria has experienced urban extensions, often poorly managed, which have generated numerous social, urban, and economic problems. In this context, this work aims to present an integrated approach combining spatial modeling, geographic remote sensing, and geographic information system to plan sustainable urban growth and mitigate the aforementioned issues. This work introduces urban sprawl simulation using the SLEUTH model, based on the cellular automata method. SLEUTH, implemented with a open-source code, facilates the simulation and prediction of urban sprawl. Applied to the Batna metropolitan area, SLEUTH is calibrated using four chronological series of data extracted from satellite images spanning from 1986 to 2020, with approximately 2,000 hectares transformed into urban land, representing an increase of about 180%. Future scenarios simulations were conducted for a 50-year period up to 2072, revealing two growth stages of urbanized areas. Beyond 2048, population density experiences a constant increase, marking the point at which Batna city reaches its urbanization limits. These findings highlight the necessity for urban planners to prepare an appropriate urban policy within a suitable timeframe. The integration of the SLEUTH model into the decision-making process is recommended to enhance urban policy management.

The study aims to evaluate the efficacy of the completed concrete canal in the urban expansion area of the city of M’sila to prevent the flood risks of river Portem, by performing a hydraulic simulation using the 2D river simulation program HEC-RAS 2D and geographic information systems (SIG), in this research and after determining The water catchment, extraction of morphological characteristics, and calculation of the maximum flow quantity Qmaxm 3/s based on the series of rainfall data for the reed station for a period of 37 years after processing it spatially in geographic information systems. The areas exposed to the risk of flooding have a direct relationship with the period of return, so that an area of 9.98 hectares was recorded in the return period of 10 years, 12.72 hectares in 50 years, and 14.31 hectares in 100 years. The study also showed the importance of using HEC- RAS 2D and (SIG) in evaluating the efficiency of the concrete channel to prevent floods and contribute to decision-making to reduce the resulting disasters.