Technical report of the Phos4You partnership on processes to recover phosphorus from wastewater

To address the growing European requirements in regard with phosphorus (P), essential nutrient but finite resource, a main purpose of the Phos4You project was to make the proof of technologies to recover P from wastewater. For this, new or existing demonstrators were used to upscale innovative processes and/or validate emerging technologies in live, operational-scale environments. This was applied to recover P from large wastewater treatment plants (WWTP) or related sewage sludge incineration plant, as well as from small WWTPs. In all cases, the recovery of valuable phosphorus materials and by-products was aimed at. The Life Cycle Assessment (LCA) was carried out for some of the most advanced processes. Three different wet-chemical processes (TetraPhos®, Phos4Life™, PARFORCE) for leaching the P contained in sewage sludge ash (SSA), with the aim of producing a marketable phosphoric acid and reusable by-products from SSA with low P content, were successfully tested. A thermochemical process (EuPhoRe®) producing SSA directly usable in fertilising products was validated. Two processes starting with a biological or a chemical leaching (Struvia™ with bio-acidification step, PULSE) successfully produced phosphate salts. Three processes removing P at small-scale WWTPs were successfully demonstrated (microalgae photobioreactor, Filtraflo™-P using adsorbent prepared out of crab-carapace, Struvia™ applied for WWTP-effluent). The LCA of the processes adopted the “system extension” and the “avoided burden” approaches, both leading to similar conclusions. Environmental advantage in terms of the mineral resource depletion were confirmed for all P-recovery processes studied whereas the beneficial effects on other categories such as climate change and fossil fuel depletion were variable between the different systems. All results of the demonstrations were the base to prepare the deployment of P-recycling in urban and rural regions. ; Um den wachsenden europäischen Anforderungen in Bezug auf Phosphor (P) - essentieller Nährstoff, ...