Microbial fuel cells (MFCs) have the potential to simultaneously treat wastewater for reuse and to generate electricity. This study mainly considers the performance of an upflow dual‐chambered MFC continuously fueled with actual domestic wastewater and alternatively biocatalyzed with aerobic activated sludge and strain of Bacillus Subtilis. The behavior of MFCs during initial biofilm growth and characterization of anodic biofilm were studied. After 45 days of continuous operation, the biofilms on the anodic electrode were well developed. The performance of MFCs was mainly evaluated in terms of COD reductions and electrical power output. Results revealed that the COD removal efficiency was 84% and 90% and the stabilized power outputs were clearly observed achieving a maximum value of 120 and 270 mW/m² obtained for MFCs inoculated with mixed cultures and Bacillus Subtilis strain, respectively.

The ability of electrochemically active bacteria to degrade natural cellulosic bio-materials suggests a promising technology for converting biodegradable cellulosic wastes into electricity in specific applications. Giant reed (GR), a wild crop abundantly available everywhere, is a potential source for cellulose. In this study, a lab-scale dual-chamber microbial fuel cell (MFC) was fueled with actual domestic wastewater loaded with different concentrations of powdered giant reed (PGR) as a new source for carbon and energy. The results revealed that in the continuous-feed tests, the maximum chemical oxygen demand (COD) removal efficiencies of 67, 79, 82, and 85% associated with maximum power generation of 162, 195, 233, 392 mW/m² were observed in MFC fueled with PGR-loaded wastewater at initial concentrations of 0, 50, 75, and 100 g PGR/L wastewater, respectively. A three-layer artificial neural network (ANN) model was used in this study to predict the efficiency of the MFC in regard to power generation. The predicted results indicated a good fit between measured and predicted data, with a high determination coefficient (R²) of 0.9993 and negligible mean square error (MSE). The fact that mixed cultures can utilize cellulose for electricity generation provides a new approach for future studies on electricity production from natural cellulose sources.

The rapid increasing population, deficiency water supplies, and global warming causing persistent scarcities and excesses have showed drinking water a reasonable resource in many places of the world. The developing of cost- efficient and balanced resources and ways for supplying the potable water in sufficient volumes is the demand of the water industry. Water contamination is a considerable universal problem. Several technically developed treatment processes, for example, attached growth process, suspended growth process, membrane bioreactor, oxidation ponds, are commonly experimented, and depended in application. However, attention to promising low-investment-cost technologies, such as slow sand filtration techniques, is especially essential. Slow sand filter (at a flow rate of 100-200 liter/h) is quite adequate water treatment process. It is also active in eliminating pathogenic microorganisms such as Giardia, E- coli, and fecal coliform, from wastewater. Addition to the capability of sand filter in elimination of pathogenic, which is assigned to the biological processes, slow sand filter can adequately exclude turbidity, suspended solids and toxic metals in remedied water. The slow sand filter treated effluent acclimates to the flow principles for domestic uses addition to commercial and irrigation uses. This study reviews the fundamental mechanism, design conditions, sand filter media, removal of physicochemical factors to ensure performing the best treatment effectiveness in slow sand filter.