The concept of alteration and management of sewage sludge at the sewage treatment plant in Szamotuły

Abstract

Under applicable law (The Act on Fertilizers and Fertilization 2007) sewage sludge produced in wastewater treatment plants is treated as waste. The article presents 5 variants of alteration and management of sewage sludge from the wastewater treatment plant in Szamotuły. Some of them include the use of green mass that can be obtained as a result of urban greenery maintenance works. For the purpose of this article there was carried out a quantitative balance of sludge, taking into account different degrees of its hydration. There were also discussed the results of an experiment conducted on the semi-technical scale. The drying process took place under a plastic tunnel with a length of 10 m. Two series of sludge drying at different outdoor temperatures were carried out. The sludge drying time in conditions of high ambient temperatures (24-36˚C) was 18 days. There was also determined the dependance between hydration and drying time at lower temperatures. In the final analysis, there were employed two basic methods of sludge treatment: solar drying and composting. The introduction of new solutions removes numerous existing sludge disposal costs. The benefits will consist in the elimination of sludge disposal costs or sludge hygienisation costs