BORTNYTSKY AERATION STATION (hereinafter – The wastewater treatment scheme is identical at each unit of the treatment facilities. The sludge formed during the wastewater treatment process is subject to processing in order to reduce its volume and disinfect it. Sludge processing takes place in special facilities - methane tanks and aerobic stabilizers. After processing, the sludge is pumped to sludge fields for further drying in natural conditions. The existing sludge fields occupy a total area of over 272 hectares. When designing the BSA, the volume of sludge in the sludge fields was predicted at 3.5 million m3. But in fact, they are three times overfilled. More than 10 million m3 of sludge has accumulated in three sludge fields and its amount is growing every day. Due to their overfilling, there is a constant threat of sludge spillage, flooding of nearby territories, and pollution of water resources. The Bortnytsia Aeration Station Modernization Project provides for reconstruction in 2 stages with the allocation of 5 start-up complexes in each stage. Considering that the construction of new structures, reconstruction and dismantling of existing ones is carried out at an enterprise operating in a continuous technological process, the following was determined as a priority: - the order of removal of individual structures subject to reconstruction from the technological process, compliance with which will ensure the normal operability of the treatment facilities; - the sequence of construction of new structures and dismantling of existing ones, ensuring the operability of the treatment facilities, is determined; - to outline (territorially) zones of construction and reconstruction in such a way as to fully ensure the movement of both construction and technological transport; During the preparatory period, the following works are also being carried out: - installation of temporary buildings and structures; - connection to sources of energy and water supply; - dismantling (demolition) of structures that are out of operation during the reconstruction; - demolition of green spaces located in the development zone; - measures to organize traffic safety during the construction period; - measures to organize the drainage of rainwater from mountainous areas. The construction is provided with water from the section of the water supply pipeline laid during the preparatory period. Source of temporary power supply - 110/6 kV substation "Lugova", 110/35/6 kV substation "Bortnychi". During the period of rehabilitation of pressure pipelines and reconstruction of the dispersive outlet, drinking water is transported by tankers, source of temporary power supply - 110/6 kV substation "Lugova", 110/35/6 kV substation "Bortnychi". Construction of structures below the groundwater level will be carried out under the protection of construction water lowering. Taking into account the geological structure of the site, hydrogeological characteristics of the soils, and the adopted methods of work, the most effective and cost-effective method of lowering the groundwater level will be water lowering using needle filter installations. Construction phase 1 includes: Start-up complex 1. Technical re-equipment of the structures of the 2nd and 3rd units in order to ensure regulatory treatment of the entire volume of wastewater for the period of construction of the new 1st unit with the installation of an air deodorization system from the block structures. Start-up complex 2. Construction of a mechanical wastewater sludge dewatering shop. Start-up complex 3. Construction of a new technological line for wastewater sludge utilization. Start-up complex 4. Construction of the new 1st unit Start-up complex 5 Preparatory work carried out: preparation of the territory, construction of new buildings and structures. As part of the preparatory work, pioneer sludge fields were liberated, work was carried out on vertical planning of the territory liberated from "pioneer" sludge fields and beyond them to the design marks, and sediment from "pioneer" sludge fields was transported. The second stage of construction includes: Launching complex 6. Reconstruction of the "Poznyaki" sewage station with the installation of an air deodorization system. Launching complex 7. Reconstruction of the "Pravoberezhnya" sewage station with the installation of an air deodorization system. Launching complex 8. Construction of a new II unit. Launching complex 9. Reconstruction of the structures of III unit of the station Launching complex 10. Reconstruction of the main channel of treated wastewater and dispersive discharges. Construction of a car farm and repair shops Wastewater treatment process When selecting a suitable wastewater treatment process, it was found that the most suitable option would be an aerobic-anoxic-oxygen process (A2O), which is carried out using an endless tray type, this alternative was also approved during the development of project documentation. In addition to phosphorus removal, additional treatment facilities are installed as a supplement to meet the requirements for phosphorus waste. A high-level coagulation tank will be added to achieve the above-mentioned goal. The choice was made based on the characteristics of the wastewater entering the treatment, as well as the wastewater flow rate entering the BSA, meeting the requirements for economic feasibility and ease of operation. The wastewater treatment process consists of a pre-treatment and primary treatment process to remove sand and mechanical impurities from the incoming wastewater, followed by a biological treatment process consisting of biological reactors (aerotanks), secondary settling tanks and disinfection using ultraviolet lamps, as well as a post-treatment process to ensure the removal of nutrients and compliance with the strict requirements in force in Kyiv. The project provides for the following sequence of the technological process for water treatment: 1. Coarse and fine screens, grease and sand traps, primary settling tanks located in one building to prevent the spread of odor. 2. Biological removal of nitrogen and phosphorus using the anaerobic-anoxic-aerobic process. 3. Secondary settling tanks. 4. Post-treatment of wastewater to remove fine suspended particles and dephosphorization of these substances. 5. Disinfection of treated wastewater with ultraviolet radiation. The sequence of the technological process for sludge treatment: 1. Gravity and mechanical thickening of sludge. 2. Mechanical dewatering of sludge 3. Thermal utilization of dewatered sludge. The BSA reconstruction project provides for the introduction of Japanese technologies for sludge treatment and utilization, which will ensure a significant reduction in its volume. Gravity and mechanical compactors are designed to reduce the volume and moisture of the sludge. At the next stage, the dewatered sewage sludge is transported to innovative sludge incinerators for thermal utilization. The combustion technology is so advanced that it almost does not use natural gas to support the combustion process. The flue gases generated during the operation of the sludge incinerators are cleaned in a wet scrubber to achieve minimal emissions of pollutants. The equipment to be installed during the Project will increase efficiency, reduce energy use and minimize negative impacts on the environment. The final product of sewage sludge utilization will be ash, which can be used in industry. Buildings and equipment that are a source of unpleasant odors are covered and have independent ventilation. According to the Project, air purification is carried out by the following methods: passing polluted air through activated carbon filters or feeding it to sludge incinerators for subsequent combustion. Construction period – 6 years.