Grey water phytodepuration systems integrated in flat green roofs

Abstract

The research about new grey water reuse systems can not only help to reduce the volume of drinkable water applied in domestic uses, besides allows to diminish the urban wastewater volume to be treated. Because of that, the proposal aims the adjustment of green roof surfaces to new uses, in relation with grey water phytodepuration systems. The main problems of traditional reed bed systems are their large dimensions, their high weight and the roots growth in the substrate subsurface. The developed system optimizes the traditional treatments with the design of industrialized channels, improving the contact between bacteria-roots and water. This optimization allows to reduce the treatment surface needed. The analysis of the most suitable species and their roots length, facilitates to diminish the channels depth; and for this reason the system is much lighter than the traditional ones. Moreover, the use of floating systems, reduce the common roots problems and diminish the maintenance requirements. Also, grey water phytodepuration systems integrated in flat green roofs, contribute not only to develop the hygrothermal benefits of green roofs, but allow to incorporate low energy water treatment systems in buildings, and to reuse it by flushing toilets and irrigation, with drinkable water saving of more than 40%