URWASTECH

ABSTRACT

The overall objective of URWASTECH project is to design, build up and demonstrate an innovative and sustainable technology based on a new approach for urban solid waste (USW), while treating urban wastewater. The project aims to integrate in a pilot plant what nowadays is considered as two independent waste management systems into a unique process.

Selective collection of USW is already set up in several countries which manage the organic matter, glass, plastics and paper as separated residues that have its own channels of recovery and treatment. However, there is still a great amount of rest waste (rest fraction) that has not been sorted out originally that needs to be managed globally. An important volume of this solid residue is managed by landfill disposal and incineration containing a high percentage of organic matter that is not valorised. However, there are also waste treatment facilities that perform several types of mechanical and biological processes in order to recover, reuse and valorise as much residue as possible before disposing to landfill or incineration. Spain, and specially Catalonia, has Eco-Parks for this purpose. Efficiency values of these facilities are important but there is still room for improvement. On the other hand, urban wastewater is currently managed in wastewater treatment plants in order to reach stringent legislation targets.

In this frame, URWASTECH proposes an innovative strategy that merges both urban rest fraction and wastewater management to achieve an improvement on urban waste valorisation rates of conventional systems. Concretely, the project is focused on the organic matter coming from these facilities. Urban wastewater will be used as solvent media for improving solid waste treatment. The proposed technology suits at National, European and worldwide level.

The strategy foreseen uses a hydro mechanical separation as a previous step for a biological treatment. Hydro mechanical unit will be composed of diverse equipment that will mix, dissolve and separate the solid residue jointly with wastewater in order to prepare the resulting dissolution for biological treatment. This equipment will be interchangeable meaning that, depending on the type of solid residue and wastewater, optimisation of the hydro mechanical process may be customised. Biological treatment will be based on anaerobic digestion for organic matter valorisation to biogas followed by membrane biological treatment and wetlands technology for wastewater treatment, obtaining:

1. More production and quality of biogas from anaerobic digestion
2. Ddepurated water ready for further applications and other valorisable fractions (plastics, metals and even biomass waste as a potential compost)