Financed with 20 million dinars of its own funds, JKP Vodovod i kanalizacija (PUC Water and Sewerage Kragujevac) is rebuilding the main Gruža pipeline. The company has announced the completion of works by September and the automation of the distribution system.
Wastewater treatment is one of the most serious problems in Serbia. There are not enough facilities, and only about 10 percent of wastewater is processed, while the European average is over 70 percent. A good example is the wastewater treatment plant in Kragujevac. Can you tell us more about this? What is its capacity, how many users are projected, what kind of technology is it?
– The Cvetojevac central wastewater treatment plant was built with German technology and put into operation in September 1990. The capacity of the plant is 1,520 l/s, or 250,000 PE. In this facility, utility, industrial and faecal water are purified to a quality that can be released to the recipient, the Lepenica River, which is verified by the issue of a water permit by the competent ministries.
In addition to its ecological importance, wastewater treatment contributes to green technologies by producing biogas. How is this done in your company?
– The Cvetojevac plant delivers three products. One is made up of water that, after purification of utility, industrial and faecal water, has such a quality that it can be discharged into the recipient. The second is separated sludge that is accumulated, compressed and deposited. The third consists of biogas as a product of the purification of water and sludge. Biogas is used for the production of electricity, which covers 70% of the plant’s electricity needs.
On the main Gruža pipeline, which supplies 70% of consumers with water in the Kragujevac area, reconstruction and replacement of sector stopcocks has been completed, which is of great importance for the quality of the water supply to inhabitants of Kragujevac
An anaerobic purification of wastewater decomposes organic matter in the absence of oxygen molecules. If the process is conducted properly, a gas can form that can be used to heat digesters and business premises and generate energy in gas generators. The total amount of gas produced is estimated from the amount of volatile solids that are decomposed. Gas production is directly related to the degree of digestion and the characteristics of the raw sludge, and depends on the process management. The basic components of the gas are: methane CH4 60-75% and CO2 30- 35%, with a small amount of 1-5% containing nitrogen, hydrogen sulphide and hydrogen.
JKP Vodovod i kanalizacija is beginning the necessary reconstruction – especially on the main Gruža pipeline, where some lengths have not been changed since 1982. What are the plans for further investment and reconstruction?
– On the main Gruža pipeline, which supplies 70% of consumers with water in the Kragujevac area, reconstruction and replacement of sector stopcocks has been completed, which is of great importance for the quality of the water supply to inhabitants of Kragujevac. In this way, it will be possible to wash out the pipeline, which will result in higher water quality across all parameters, especially turbidity. This pipeline was built in 1983 and since then no serious work has been undertaken on it. We started replacing the stopcocks in December 2018. The plan is to complete the entire job by September this year. All works are financed from company income, and the total amount of investment for these purposes is over 20 million dinars. For the coming period, we have planned the reconstruction of the entire main pipeline and automation of the distribution system.