| Abstract [eng] |
There are 32 of 117 rivers that are affected by a point source pollution and do not comply with good water quality requirements in Lithuania. In order to solve this problem, the application of biological filtration for a tertiary wastewater treatment is proposed. During the study, three trickling filters were installed in a technical room of Nemenčinė WWTP. The filters were filled with three different media: stone wool Growcube, stone wool Paroc WAS 35 and foam rubber. The biologically treated wastewater was continuously supplied to the filters maintaining the same surface load – 0.07 m3/m2/min. According to the results, the highest removal efficiency of COD, BOD7 and SS (15.0 %, 21.8 % and 43.4 % respectively) was reached in filter 1 that contained the stone wool Growcube media. The highest removal efficiency of NO3-–N and NH4+–N (13.2 % and 19.7 % respectively) was also reached in the filter F1 containing the stone wool Growcube media. As well as nitrogen compounds, the best removal of PO43-–P was observed in the filter F1 with an average removal efficiency of 21.9 %. Thesis consists of: 67 pages of text, 32 pictures, 14 tables, 66 bibliographical entries. |
