Physico-chemical caracterisation of produced lime artisanally in the isced of Luozi in the Kongo Central/DRC]

Abstract

The aim of this work is to characterize the lime produced artisanally in the city of Luozi, that produced at the A28 laboratory of the Faculty of Sciences and technologies of the University of Kinshasa starting from limestone of Luozi, to determine of it the standard, quality in the water treatment, compared to the produced lime industrially used for the water treatment. Seven sites of Luozi producing lime artisanally are identified and of the physicochemical analyses methods like the diffraction of x-rays, the calcimetry and the chemical treatment are put at contribution for a physicochemical characterization of these limes produced artisanally, at the laboratory A28 and that produced industrially. Being the gravel bank-test, the seven sites of Luozi gave an average value of pH of 7,03 and the lime produced at the A28 laboratory and industrially gave pH of 7,30 and 7,25 respectively; the international standard required is to have a pH between 6,50 - 8,00. The diffraction of x-rays analyses of the powder with lime showed a content of CaO in the limestone rock of the various sites of Luozi with an average of 90,2%.Two of seven sites of Luozi (Matokin and Bimba) gave 94,0 % and lime 93,9% (CaO) and those produced at the A28 laboratory and industrially gave 95,2 % and 97,3%.These four samples met the international standards required for the water treatment according to the test of the expertise on lime (92% of purity in CaO).
This study made it possible to know other oxides which accompany lime CaO such as SiO2, Al2O3, Fe2O3, MgO, SO2, K2O and Na2O and to determine her purity.The calcium oxide (CaO) is in a majority and the other oxides are minority.