A new European LIFE+ project on pilot plant demonstration of a new urban WWTP concept has been awarded to GENOCOV (LIFE14 ENV/ES/000633) led by Julián Carrera together with María Eugenia Suárez-Ojeda and Julio Pérez.
The current urban wastewater treatment plant (WWTP) requires a minimum energy consumption of 8-15 kWh/inhabitant/year to meet the legal requirements of effluent discharge of organic matter, nitrogen and phosphorus. This means a significant economic cost and also noteworthy greenhouse gas emissions. The challenge of SAVING-E is to radically redesign the urban WWTPs in a way they become energy-producers rather than energy consumers, without affecting its performance or even improving it. SAVING-E aims at demonstrating, at pilot scale and with real urban wastewater that the energetic balance of an urban WWTP can be severely improved at both, high and low temperatures (as far as 10ºC).
SAVING-E technology uses most of the entering organic matter for biogas production purposes by designing a first biological step with low oxygen consumption and high biomass production, i.e. with very low sludge residence time (1 day or less). The biomass produced in this step, therefore, would have a very favourable methane production potential, greater than the achieved in the current urban WWTPs. Then, SAVING-E technology is able to biologically remove nitrogen in the mainstream without the need of organic matter. SAVING-E uses the autotrophic biological nitrogen removal (BNR) for this aim with a novel two-step approach. This novel approach consists of two reactors, a first aerobic partial nitritation reactor followed by a second anammox reactor. The application of autotrophic BNR to the mainstream severely reduces the aeration costs compared with the one of current urban WWTPs. Moreover, the novel two-step approach for autotrophic BNR represents an improvement compared with one-step autotrophic BNR because is able to stably work at low temperatures (10 ºC).
Therefore, the main objective of this project is to demonstrate, in a relevant environment at pilot scale, the feasibility, applicability, replicability and transferability of the SAVING-E technology.