DECONTAMINATION OF SLUDGE THROUGH THE USE OF A STABILIZER ADAPT MADE BY "DEVNYA CEMENT" AD

The large amount of sludge that is generated in wastewater treatment plants /WWTP/ and the lack of drying fields to stabilize them necessitates the conduct of this study. The use of sludge in practice can be a source of biological contamination of soil, water and plants, including pathogenic microorganisms. Regardless of the developed normative documents, there are a number of problems in practice that limit the realization of sewage sludge. One of these problems is related to the disturbed microbiological parameters in most treatment plants. Sludge storage is used as the only way to eliminate pathogenic microorganisms. This method is not effective enough since it requires large areas for sludge storage. The purpose of the study was to determine the possibility of decontamination of sewage sludge using an ADAPT stabilizer for waste treatment produced by ‚Devnya Cement‘ AD. For the preparation of the cement clinker, mainly natural rock materials are used, which, after crushing and grinding, form a "raw material mixture" consisting of natural survins and industrial products containing the major minor oxides - CaO, Si02 , Al2 O3 and Fe2 O3. Fresh sludge from WWTP Varna was used, treated with 20, 25 and 35% of the stabilizer. The sludge was analyzed before and after treatment by agrochemicals and microbiological parameters. It was found that the most effective treatment was with 20% sludge dry stabilizer treatment for a period of 20 days. Treatment of the sludge with the stabilizer does not have a negative effect on their chemical and agrochemical characteristics.