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 the characteristics of sewage sludge from wastewater treatment plant of khenifra city, Morocco. Experiments were performed for determining the mineralogical composition, chemical properties, loss of weight, the rate of the calcium carbonate and moisture. Furthermore, the geotechnical parameters deal with the Atterberg limits, water content and Sand equivalent of the sewage sludge material. The purpose of this paper is to present the available information on the various components of sewage sludge to explore the possibility of exploiting this waste in building materials Results show that sewage sludge has neutral pH value around 6.93 and contains organic matter. Moreover, the sludge is 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 the presence of quartz (SiO2), hematite (Fe2O3), aluminum oxide (Al2O3) and calcite (CaO3).The result of the geotechnical properties of sewage sludge obtained indicates a very high value for a liquid limit of 126%, a plastic limit of 100% and the 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 the Khenifra city, the utilization of sewage sludge into building materials such as in brick making, ceramics making and in the manufacture of cement are possible, because sludge composition is similar to the raw to construction materials.