Assessment of organo-mineral fraction during storage of oil refinery sludge

The biotransformation during storage of petroleum refinery sludge was evaluated by physicochemical and spectroscopy analyses. The abatement rate of organic matter  has reached 50.5% after 14 months of storage. The humic substances have decreased of about 49% at the end of storage indicating that the OM was mineralized into inorganic compounds (CO2, N2…). The XRD of dried samples shows the presence of a large proportion of silica (SiO2), carbonate (CaCO3), Hercynite (Al2FeO4) and hemihydrate calcium sulphate (2CaSO4.H2O).  Hematite (Fe2O3) and anhydrite (CaSO4) were found as a new appeared phase. Pb, Cd, Cr, Cu, Ni and Zn were the most identified heavy metals in the petroleum samples. Their increase at the end of storage was explain by the organic matter degradation. FTIR analysis show that the carbonate, sulphate and silica are the most identified compounds beside the organic matter

Assessment of organo-mineral fraction during co-composting of sewage sludge-lignocellulosic waste by XRD and FTIR analysis

This investigation focuses mainly on highlighting the contribution of the IR spectrum of the mineral matrix in co-composts after removing the organic phase by slow pyrolysis. The mineral matrix is still confusion subject in the interpretation of FTIR spectra of co-composts. The XRF and XRD analysis of the low pyrolysis substrates of sewage sludge and date palm waste during six months of co-composting, show that the mineral fraction is homogeneous in the samples and that the inorganic matrix consists mainly of silica and carbonates including a residual portion remaining after pyrolysis.The comparison of FTIR spectra of heated samples at 105°C and 650°C shows that the 3500-3280 cm-1 region characterises essentially the hydroxyl groups OH (ν(OH)) of water molecules. The observed bands in this region provide information on the co-compost hydrophilic nature but can only provide limited information about the humic substances composition. The band at 1035 cm-1, assigned commonly to organic material, which persists after the thermal treatment, should be assigned for the Si-O vibration of silica