In low-income countries, the discharge of untreated fecal sludge directly into the environment is a common practice that poses a threat to both environmental and public health. Planted drying beds (PDBs) are a promising and low-cost option for treating fecal sludge. Therefore, in Africa, the use of PDBs for treating fecal sludge is increasingly valuable due to the technology's high efficiency, especially in tropical climates. This paper presents a literature review on the use of PDBs for treating fecal sludge in Africa, focusing on current research requirements and directions. This review shows that Echinochloa pyramidalis appears to be the most effective indigenous species used for this purpose, while also highlighting the lack of stability in the design and implementation models of PDBs. Standardizing and generalizing implementation methodologies for PDBs in Africa, researching new native and efficient species, and testing combinations of different species in the beds would all be beneficial.
The present study aims to fill the data gap analysis in urban wastewaters characteristics in Benin and its statistical analysis. Physicochemical parameters such as pH, electrical conductivity (EC), Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD5), Total Kjeldahl Nitrogen (TKN), Total Phosphorus (TP) and UV Absorbance at 254 nm, were determined on domestic (greywater and blackwater) and industrial (hospital, pharmaceutical and commercial laundry) wastewater in Cotonou city. Analysis of variance showed a strong significant difference in the physico-chemistry of the various effluents. The pharmaceutical wastewater has the highest concentration of organic pollution (COD = 5,912 ± 1,026 mg/L, Abs.UV254 = 2.667 ± 0.327 cm−1). The organic load of blackwater is mainly in particulate and biodegradable form. Besides, the correlation study showed the limits of pH and EC as an indicator of organic load. Furthermore, the choice of COD or BOD5 as the main design parameter would be limited to blackwater treatment. Abs.UV254 was found to be the parameter having a strong relationship with other parameters of all effluents except blackwater. It then takes priority over COD for the treatment of greywater and industrial wastewater. For future wastewater treatment plant design, we recommend to consider Abs.UV254 as an important parameter.
A class of amorphous carbonaceous materials with large porosity and internal surface area is referred to as “activated carbon,” or AC. Coconut shells, coal, and wood are the basic sources of ACs. Anthracite and bituminous coals have been the main sources of AC until recently, although AC may be made from any carbonaceous material. AC is an extremely effective adsorbent. It may be used to clean, dechlorinate, deodorize, and decolourize both liquid and vapour applications because of its large surface area, pore structure, and high degree of surface reactivity. Since the removal of contaminants requires carbonaceous materials with a high degree of porosity, well-developed surface area, and distinct functional groups, use of ACs is one of the finest methods for eliminating pollutants from aqueous solution and the atmosphere. ACs are also cost-effective adsorbents for a variety of sectors, including water purification, food-grade goods, cosmetics, automotive applications, industrial gas purification, petroleum, and precious metal recovery, mostly for gold. The classification, characteristics, and usage of AC are the main topics of this chapter.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.