Proceedings

Three brief bullet points:

• The system involves the following processes: Fill and drain VSSF and intermittent aeration supplied in the saturated bottom layer. Artificial aeration applied intermittently allowed simultaneous nitrification and denitrification to occur, resulting in a higher removal of total nitrogen from wastewater, compared to a conventional down-flow and low-load VSSF used as a control line.
• This system allows for a considerable land area reduction: from the 4m²/PE suggested by the national guidelinesto 1.9 m²/PE. This was achieved by means of a slightly complex system, made only of aeration pipes, a small bowler and an automated valve.
• This innovative configuration can be used as a permanent solution for the wastewater treatment of small communities, or as an additional one to be used during peak seasons, in order to guarantee the removal of extra-loads.