The existing, obsolete, hydraulically and biologically overloaded wastewater treatment plant could not provide an acceptable reduction of pollutant levels, and it became an obstacle to the development of the settlement (prohibition of new house connections)
The owner municipality applied for an EU co-financing, and BDL Ltd was awarded with completing the required feasibility studies, permitting and detailed plans of the new treatment technology.
The technology train includes: mechanical treatment (fine screens, aerated grease and sand removal), BIOCOS type aerobe activated sludge treatment, with chemical dosing (additional phosphorous removal). The BIOCOS (BIOlogical COmbined System) technology unites the advantages of the „classical” continuous flow activated sludge processes and the SBR technologies, providing flexible operational conditions.
The excess sludge gets thickened, and after that it can be further thickened and/or dehydrated with a combined belt press.
The trial period was conducted successfully. The discharge regulation, and the trial period results for the relevant pollutants are the followings:
| discharge limit | trial period results | ||
| KOIkr | 75 | 30 > | g/m3 |
| BOI5 | 25 | 10 > | g/m3 |
| Total-N | 25 | 15 > | g/m3 |
| Total-P | 2 | 2 > | g/m3 |
| TSS | 35 | 10 > | g/m3 |
| NH3-NH4-N | 5 | 1 > | g/m3 |
