IMDEA Water has a pilot plant based on technologies of treatment through land application systems that serves to carry out research and improvements in the purification of wastewater for small populations.
This land application system is managed by members of the reclaimed water reuse line.
A land application system is an agroforestry system, in which pretreated wastewater is applied to a soil surface with arboreal and herbaceous vegetation. The purification in the land application systems is done through the joint action of the soil, the microorganisms present in it and the plants, through a series of physical, chemical and biological processes.
The installed land application system (image 1) has an area of 60 m2 and has planted poplars (clone I-214) with a density of 10,000 trees/ha. This is a fast growing plant species and, therefore, has high water and nutrient requirements. This allows to maximize the performance and debugging capacity of the system. In addition, the plantation undergoes short shifts (2-3 years).
The wastewater from the institute is taken to an imhoff tank to perform the pretreatment. From a pumping well installed at the outlet of the tank, wastewaters are sent, under pressure, to a rupture chamber (image 2), in whose outlet the pre-treated water is distributed to a first land application system and distributed to another different pilot. of residual water treatment and that works in a complementary way. The effluent of this last pilot is used to irrigate a second land application system, of characteristics homologous to the first, and which works as a tertiary treatment. To this second land application system, and since the organic matter load it is going to receive is much lower, organic amendments of plant origin have been added in such a way that the organic carbon content is increased and the elimination of contaminants is enhanced through microbial stimulation and the increase of sorption processes.
These systems make it possible to carry out the integral treatment of wastewater from IMDEA Water, as well as to know and compare the response of both filters to the treatment of water of different qualities (image 3).