SVARTVATTENSYSTEM I HAMMARBY SJÖSTAD? – Systemanalys och förslag på utformning av system / Blackwater treatment system in Hammarby Sjöstad? – System analysis and design
As a part of the environmental programme for Hammarby Sjöstad, a separate system for blackwater and organic household waste has been considered. Four different systems have been compared using a system analysis approach. Design issues considered were source separation of urine, use of vacuum toilers, and advanced nutrient recovery processes such as Reverse Osmosis (RO). All of the studied systems have low emissions of eutrophying compounds. Other environmental effects are mainly related to the amount of exergy used at each system. Systems with conventional low flush toilets and “high-rate” anaerobic treatment (e.g. Upflow Anaerobic Sludge Blanket reactors) combined with nutrient recovery processes such as RO are preferable due to their high nutrient re-cycling potential, their relative robustness concerning water use, and a higher probability of public acceptance.