Innovation and Circular Economy in Water Sector: The CAP Group

Abstract

CAP Group is the 100% publicly-funded company that manages the integrated water service in the metropolitan city of Milan. It provides municipal water and wastewater services to over 2 million inhabitants, with 59 wastewater treatment plants where almost 70,000 ton/year of dewatered sludge is produced. Today’s challenge is to respond to climate change, finding new solutions for the recovery of biofuels (biomethane), nutrients (e.g., phosphorus) and energy by water cycle: this is the basis of our Master Plan for the bio-refineries, part of the #Waterevolution launched by CAP Group. The European Commission has adopted an ambitious new Circular Economy Package to stimulate Europe’s transition towards a circular economy that will boost global competitiveness, foster sustainable economic growth and generate new jobs. How important are the new series of actions on water reuse? How beneficial could these be for the circular economy? The existing municipal wastewater treatment plants can be renovated and integrated to become multi-purpose urban bio-refineries that serve citizens in the treatment and valorization of municipal waste streams, such as wastewaters and organic waste, towards a coherent urban strategy. Existing anaerobic digesters have residual treatment capacities that allow for the co-digestion of sewage sludge and the organic fraction of municipal solid waste, which will increase the recovery of biofuels (biomethane) and nutrients (e.g., phosphorus) in existing treatment plants. The combination of eco-innovative technologies with anaerobic co-digestion allows for the integrated recovery of biomethane, phosphorus, and biopolymers. In such a scenario, CAP Group can and wants to deliver a circular economy approach. To this aim, CAP Group has defined a territorial Master Plan to implement eco-innovative and energy-efficient solutions for renovating existing wastewater treatment plants close to the circular value chain by applying low-carbon techniques for recovering materials that are otherwise lost. In order to include leading edge sustainable solutions, the Master Plan considers synergic interaction with the major, ongoing innovative actions of European Horizon 2020, such as the “SMART-Plant” project coordinated by the Italian University of Verona. The project was undertaken by CAP Group in August 2016 at the water treatment plant in Niguarda-Bresso (Milan) with the scientific support of the CNR and the technological collaboration of FCA. It consists of the production of biomethane from sludge coming from water treatment plants, as a sustainable, ecological and innovative alternative to the traditional sludge disposal methods. A Fiat Panda Natural Power car will travel 80,000 km using the biomethane produced as fuel by CAP Group.