Planning services for the overall concept of intensified phosphorus recovery from the process water of the Steinhof wastewater treatment plant in Braunschweig and integration into the existing facility

The Braunschweig Wastewater Association intends to expand the Steinhof wastewater treatment plant within the framework of the "P-Cycle" project for intensified phosphorus recovery from process water. The central wastewater treatment plant of the Braunschweig Wastewater Association (AVB) in Steinhof treats wastewater from around 250,000 inhabitants and numerous commercial enterprises in the city of Braunschweig daily, making it one of the largest wastewater treatment plants in Northern Germany. The volume of wastewater treated at the Braunschweig wastewater treatment plant corresponds to a daily average load of 350,000 population equivalents (EW). With the Braunschweig Model for Water Reuse (irrigation of treated wastewater and currently also sewage sludge on agricultural land, cultivation of energy crops and biogas production), the city of Braunschweig enjoys nationwide model status regarding sustainable circular economy for water, nutrients, and energy. Against the background of the future applicable requirements of the AbfKlärV for phosphorus recycling from sewage sludge and the concept of the Braunschweig Model, in addition to the irrigation of treated wastewater, to circulate nutrients regionally, a process for increased phosphorus remobilization (Peco process, ISWW-TUBS) was successfully tested in a partial flow at the Steinhof wastewater treatment plant within the framework of the BMFTR-funded research project P-Net. The subject of the contract is the conceptual integration of the Peco process into the existing facility of the Braunschweig wastewater treatment plant. This includes the planning and implementation of the overall concept, the core of which consists of a mesophilic, heatable remobilization reactor (> 3000 m³). In addition, further thickening/dewatering units, e.g., a vacuum belt filter as an extension of the existing struvite precipitation plant, and the corresponding machine and EMSR technology are to be planned. Furthermore, exhaust air treatment and a machine building for the additional machine technology must be provided. To ensure compliance with the applicable limit values, an acid dosing station for chemical P-release in the digested sludge is already being installed at the Steinhof wastewater treatment plant prior to this contract, which is to be used as a policing stage for the Peco process and must also be taken into account in the planning and integration of the Peco process. The goal of the measure is to comply with the P recovery according to AbflKlärV, so that the dewatered sewage sludge can achieve < 18 g P/kg dry matter all year round, in order to create more flexible disposal routes for the Braunschweig sewage sludge. To maximize the phosphorus recovery rate and ensure the long-term regional phosphorus supply, as well as to strengthen the "Braunschweig Model" as a sustainable approach to circular economy, a funding application has been submitted. The funding includes scientific support for the planning and implementation of the measure by the Institute for Urban Water Management at TU Braunschweig. The planning services will be commissioned subject to the approval of funding. The total volume of the measure is estimated at approx. €10.5 million gross. Construction is planned to begin in early 2028. Commissioning is scheduled for the end of 2028, so that the requirements at the Steinhof wastewater treatment plant will be met when the legal requirements for P recycling come into force. Depending on the approval of funding, a phased commissioning is planned. A suitable general planner is sought for the necessary planning services to provide the following services: - Object planning for engineering structures according to §§ 41 ff. HOAI, service phases 1 to 9 - Specialist planning for machine and process technology according to §§ 53 ff. HOAI, service phases 1 to 9 - Specialist planning for EMSR technology according to §§ 53 ff. HOAI, service phases 1 to 9 - Specialist planning for structural analysis according to §§ 49 ff. HOAI, service...