Characterization of sludge waste products from wastewater treatment plant of Khenifra city in Morocco

Abstract

To promote the utilization of sewage sludge as alternative building materials, a study was carried out to examine thecharacteristics of sewage sludge from wastewater treatment plant of khenifra city, Morocco. Experiments wereperformed for determining the mineralogical composition, chemical properties, loss of weight, the rate of the calciumcarbonate and moisture. Furthermore, the geotechnical parameters deal with the Atterberg limits, water content andSand equivalent of the sewage sludge material. The purpose of this paper is to present the available information onthe various components of sewage sludge to explore the possibility of exploiting this waste in building materialsResults show that sewage sludge has neutral pH value around 6.93 and contains organic matter. Moreover, the sludgeis composed of a significant amount of oxides and metals. The value of net calorific value (NCV) is 1888.91 Kcal kg-1.As well as, the mineralogical composition of sludge has been determined by X-rays diffraction (XRD) show thepresence of quartz $(SiO_2)$, hematite $(Fe_2O_3)$, aluminum oxide $(Al_2O_3)$ and calcite $(CaO_3)$.The result of the geotechnicalproperties of sewage sludge obtained indicates a very high value for a liquid limit of 126%, a plastic limit of 100% andthe plasticity index of 25% and 128% water content.Based on the data obtained from the characteristics of sewage sludge produced by wastewater treatment plant in theKhenifra city, the utilization of sewage sludge into building materials such as in brick making, ceramics making andin the manufacture of cement are possible, because sludge composition is similar to the raw to construction materials.