Characterization and Application of the Makoua Clay in the Chemical and Bacteriological Depollution of Gutter and Well Waters of Brazzaville

Abstract

In this work, the authors made aquatic filters according to the formulation “clay stabilized at 4% of cement mixed with 4% of kambala sawdust and 10% of white sand” then heated to 1050°C to decontaminate the waters of gutters and wells. The authors carried out geotechnical, geochemical, thermal, infrared spectroscopy, and scanning electron microscopy that analyzed the clay material. Geotechnical analyzes have shown that this material is made up of 22% thin sand, 22% of silt, and 56% of clay with 26 plasticity index. The geochemical analysis showed the presence of trace elements shared out as follows: 3% of alkaline metals, 24% of alkaline earth metals, 46% of transition metals, 10% of metal, 16% of lanthanides, 1% of actinides. The most abundant trace elements are barium (19%), vanadium (12%), chromium (11%) and zinc (9%). The thermal and microscopic analyzes revealed the kaolinitic nature of materials. The chemical depollution studies have shown elimination yields of 50% - 52.38% of sulphates; 77.33% - 85.19% of phosphates; 34.85% - 88.49% nitrates; 91.3 - 100 of sulphides; The removal of bacteriological pollution are 92.8% - 98% of total germs; 94% - 97% of total coliform and 95% - 98% of E. coli.