Country
Slovakia
Application
Secondary treatment
Water source
Wastewater
Filtration solution
2 x 48" multimedia filters
Background
The wastewater facility of the city of Strazske, Slovakia, is a secondary level facility built in the 1960s and deals with municipal sewage only. Multiple reasons brought the city to upgrade the system; the increase in population, rise in the standard of living which result in an increase in the daily flow into the facility to a rate of 720 m3 per day. Furthermore, the facility is in very poor technical and operational conditions. Upgrading the facility is only an interim measure until a new facility is built, with capacity meeting the quality requirements of tertiary treatment, environmental reuse and transfer of releasing of water to the nearby river.
Challenge
This project includes installation of a tertiary treatment system downstream of a bio-reactor, including a unique carrier technology for increasing the biodegradation efficiency of the organic material and reduction of the BOD, COD and TSS. One of the main challenges we faced was installing the system inside the existing building which houses the process pumps. Due to the extreme weather conditions in the region, with winter temperatures of -20°C, the filtration equipment had to be installed in a heated structure in order to prevent freezing. This required a unique design of the system, making it fit into the available space in the building. In addition to the installation planning in the building, we were required to design a pumping and distribution system for non-uniform hourly flow rates since the facility’s sewage collection system works at varying flow rates, in the range of 5 to 40 (M3/h).
Solution
Amiad designed and supplied a system comprising of two 48” automatic multimedia filters, operating at an internal pressure of up to 3 bars and a flow rate of up to 30 (M³/h). In addition to the central multimedia filtration system, Amiad also supplied an in-process pump system, creating a pressure of 3 bar at the filtration system’s inlet. Wastewater is fed to the process pumps from a pit at the outlet of the biological reactor. In addition to the multimedia system, the design challenge also included the in-process pump control system, with level sensors and control panel, which dealt with the non-uniform flow rate.
Results
The facility began continuous operation in the beginning of July 2011, releasing water to the river at the required quality