Wastewater management has been one of the most pressing urban problems for some time. The need to optimise the treatment of this waste to minimise its environmental impact, and to do it as efficiently as possible using the lowest amount of energy, has driven the development of new technologies. The most recent example of this is the Faro-Olhão wastewater treatment plant, constructed by ACCIONA Agua and officially opened in November.
Nereda®: Innovation to safeguard the environment
The Faro-Olhão wastewater treatment plant, in the Algarve region in Portugal, which was constructed in less than two years with a budget of €13.9 million, will serve a population of more than 110,000 people. The treatment plant is located one kilometre from the town of Olhão, in an area of great environmental value that is home to protected species. The need to reduce the plant’s impact on this privileged environment as much as possible led to the use of one of the most modern wastewater treatment technologies: Nereda®.
ACCIONA Agua has employed this innovative technology in the Faro-Olhão wastewater treatment plant, thanks to the exclusive license that it holds for Spain, Portugal and Italy, after signing an agreement with Royal HaskoningDHV. Nereda® is based on the unique characteristics of aerobic granular biomass. These granules have outstanding sedimentation properties and this new method removes the need for a settling phase, which is essential in conventional SBRs (Sequential Batch Reactors) but requires a lot of time. Furthermore, all the biological treatment processes (removal of carbonic matter and nutrients such as nitrogen and phosphorus) take place simultaneously in the granules, requiring just a single tank.
There are several advantages to this method of treating wastewater, in terms of profitability and environmental impact. Firstly, it requires just one quarter of the land area of conventional facilities with activated sludge, and the process generates energy savings of between 30 and 40%. Secondly, it reduces the plant’s carbon footprint by 50% and cuts down odour emissions. Furthermore, Nereda® can be used in both new plants and existing facilities. In the case of the latter, it can increase capacity and improve performance, and is an excellent solution for older plants in which intensive processes consume a lot of energy, while in new plants the reduced size is an important factor.
Fewer emissions and better energy performance
ACCIONA Agua’s ongoing work to improve treatment processes is also highlighted in initiatives such as the recently concluded Life Celsius project.
Over the course of three years, Life Celsius has demonstrated the viability of a lower cost wastewater treatment system that also emits less CO2. The key element in the process is the use of a type of bacteria that does not require oxygen to metabolise and uses the ambient heat of the region instead. This was a determining factor when deciding the location of the pilot plant, at the Archena wastewater treatment station, since wastewater in the Murcia region arrives at the treatment plant at a temperature between 15 and 25°C.
The use of digitalisation in water treatment
New digital technologies are essential for developing new solutions. For example, automation and the use of artificial intelligence not only enable us to know what is going on at the plant at any given time, but also to anticipate problems. Augmented reality is another extremely useful tool in this field, as ACCIONA Agua has shown at the La Almunia de Doña Godina wastewater treatment plant in Zaragoza. The “Augmented Facility Management” project combines virtual and augmented reality as tools for training employees, as well as for maintaining the facilities. Operators can use virtual reality systems to familiarise themselves with daily tasks at the plant without needing to be physically present. This remote access not only allows multiple students to train simultaneously, but also eliminates all the occupational risk. Furthermore, augmented reality allows operators to monitor the plant in real time and to remotely control its operations from any location around the world.
Innovative biological processes, energy optimisation systems, artificial intelligence and augmented reality are all new technologies that ACCIONA Agua is employing to make advances in wastewater management, and demonstrate the company’s commitment to sustainability and the environment.