Throughout the last few years the efficiency of the existing wastewater cleaning systems has been considerably improved. The sewage networks for industrial and household wastewater have been completely renovated and the rain and drainage sewage has been partially reconstructed. The local cleaning equipment has been renovated (oil and water separators, sedimentation tanks) and new ones have been constructed, which has prevented petroleum products from entering the wastewater that is discharged.
In order to achieve additional improvements as regards the water quality, in 2014 was opened a new water treatment plant for waste water from rain-drainage sewers. Design and capacity is 250 m3 / hour, and the investment exceeds 10 million leva. With new sewer branches, the rain and drainage water from the entire industrial site of the company will be conveyed to the treatment plant for purification to achieve the parameters required for discharge. The project envisages compensating basins to retain the entire water volumes during heavy rains – there are two of those in the region of the plant with a total
capacity of 46,500 m3. The technology, design and equipment were developed by the German company ЕnviroChemie. The process is fully automated. The control software is PCS-7, V8 developed by the German company Siemens. It is implemented by the Automation Group of
Aurubis Bulgaria AD. The construction activities of the project are implemented by a consortium called “Port Build Engineering”, which consists entirely of local companies (Polistroy 21, Oloplast, Reizh, Trans Build and Himgardsystem).
The efficient use of the water resources and the decrease in water consumption is another corporate aim in which there has been a substantial improvement in implementation. The total water consumption at Aurubis Bulgaria in 2017 decreased by 30 % compared to the consumption in 2003.
The specific metal water emissions (g/t) per ton of copper output have decreased by 97% since the year 2000.
The main steps for decreasing the metal water emissions were as follows:
- commissioning of the 2nd and 3rd step of the Industrial waste water treatment plant (2005 – 2006)
- reconstruction and modernization of the acid sewerage system (2006 – 2008)
- reconstruction and modernization of the household (2010 – 2011) and rain-drainage (2012 – 2013) sewerage systems
- commissioning of the rainwater treatment plant (2014).