Abstract:
Textile industries generate large volumes of sludge as a result of their activities. The disposal of this sludge is a serious environmental concern due to the presence of toxic and heavy contaminants. Additionally, large volume and mass of sludge create burden for, sludge management in the industry. This study aimed to characterize the industrial sludge and evaluate its capability for land application. The sludge samples were collected from the sludge drying beds and filter press areas from October to December 2022 and then analyzed in a laboratory for parameters including pH, electrical conductivity, volatile solids, fixed solids, organic matter, organic carbon, moisture content, total nitrogen, total phosphorus, heavy metals, total coliforms, and fecal coliforms. Appropriate descriptive statistical analysis, involving a combination of qualitative and quantitative data, was used to determine the physicochemical and heavy metal content of the sludge. The results from the physicochemical analysis showed that the sludge has appropriate conditions for land use, with a near-neutral pH, satisfactory moisture level, and promising organic matter, nitrogen, and phosphorus content. The concentrations of Zn+2, Pb+1 and Fe+3 within the acceptable regulatory standards (FAO/WHO with the average values of 177.467, 64.063, and 735.3 mg/kg dry sludge, respectively. The total coliform and fecal coliform counts (8.5 and 8.1 MPN/g, respectively) also met the regulatory standards, However, the concentrations of Cr+6, Cu+2, and Cd+1 were higher than the permissible limits and may cause long-term effects on land use with the average values of 126.66, 261.86, and 10.04 mg/kg, respectively). Therefore, sludge in the Bahir Dar textile can be a potential for land application in the agricultural land. However, due to increasing concentration of Cu and Cd from the recommended values, there should be pretreatment systems before uses. Further studies required for further analysis of sludge.
Keywords: Bacteriological, Characterization, Land application, Physicochemical, Textile