improving the soil quality with organic matter content and presence of elements such as n, p and k are some of sewage sludge benefits. adjusting carbonaceous materials such as plant wastes to dewatered sludge compost increases its moisture and improves c/n ratio. so dewatered sludge has low c/n ratio and should be mixed with bulking agents. this study was performed in a three months period of t...

Solubilization of sewage sludge creates favorable conditions for anaerobic microorganisms to produce biogas. In this paper, we quantify the effect of heating pretreatment on the degree of solubilization of sewage sludge. The pretreatment process was carried out using a lab-scale industrial microwave unit (2450 MHz frequency). Response surface analysis was applied to determine the combination of...

A significant nutrient load can be generated internally by publicly owned treatment works (POTWs). These nutrients can be found in the reject water, also known as side streams, of many municipal wastewater and sewage sludge treatment processes. These side streams include the reject stream from membranes, supernatant liquid from sludge digesters, and the centrate/filtrate return stream from sewa...

The addition of lime as Ca(OH)2 to sewage sludge to destroy pathogens (Escherichia coli), was evaluated also in relation to heavy metal bioavailability. The obtained results show that the use of calcium hydroxide at the dose of 3% effectively destroyed pathogens ensuring the stability at high pH values over long period and the duration of the sewage sludge stabilization. In general, lime additi...

Sewage and sludge samples were collected from rural areas of Vellore district. The metals like Cu, Zn, Cd, Pb, Fe, Ca and Mg were determined by Inductively coupled plasma atomic emission spectrophotometry (ICP-AES). For this determination HCl - HNO3 and 4N HNO3 extracts were used. The total organic carbon (TOC), chemical oxygen demand (COD) and organic matter (OM) have also been determined to e...

KVWPCA operates a waste water treatment plant in Leechburg, Pennsylvania, about 40 kilometers (25 miles) northeast of Pittsburgh on the flood plain of the Kiskiminetas River. From 1976 to 1993, KVWPCA treated sewage sludge by incineration. KVWPCA disposed of the resulting sewage sludge ash by mixing it with water to form a liquid slurry and pumping this material into an onsite lagoon. Discharge...

An increasing amount of sewage sludge requires reasonable management, whereas its storage might be environmentally hazardous. Due to the organic matter and nutrient presence in sediments, it may be used as organic fertilizer. However, beyond the valuable contests, sewage sludge can also contain toxic or dangerous ingredients like heavy metals. Therefore, there is a need to develop methods for r...

 This paper presents a mathematical model of the cylindrical particle combustion in a fluidized bed reactor. This particle is composed of sewage sludge. The model performs a mathematical description of the physical and chemical phenomena that occur during particle combustion. The uniform particle model without ash accumulation is proposed. Sewage sludge is considered composed of three fractio...