Waste management is a major stakeholder of a nation that aspires for development. Organic biodegradable waste invades the city of Kinshasa: streets, green spaces, aquatic environments and in other cities of the country where their management becomes a serious problem. In this work, three organic substrates: cow dung, sawdust and soil (fertile soils) were recycled by mixing them in the form of scenarios (dung alone, dung with sawdust and dung with soil). Recycling was carried out using the vermicomposting technique. The trials have yielded a fertile manure that meets ecological standards and earthworms that are increasingly being considered in the production of animal proteins and economically profitable
The juice that percolates through the hospital sewage and that loads of pollutants must be eliminated. Our study contributes to the establishment of a purification system of hospital wastewater was expensive and effective. The process (stabilization coupled to bio filtration) involves aquatic plants such as Azolla and sand filtration. It thus improves the drainage conditions of the hospital effluents by dramatically reducing the pollution load. This technique decreases and lowers the organic filler according to the conditions imposed. The bio filtration has a specific behavior with respect to the leachate and increases the purification performance of wastewater. So by applying this technique, our study shows a reduction of 77.4% of the chemical oxygen demand (COD), 68.6% of turbidity, 94% of nitrates and phosphates 95% for a residence time of 8 am in the lagoon. This technics following the filter coupling shows a reduction of pathogenic microorganisms. The lagoon level the concentration of organic matter (OM), nitrogen and phosphorus decreased. This study is an important step in the design of a wastewater treatment plant wastewater university clinics in Kinshasa, DRC.