22th March, 2016.- The big goal of Acciona Agua with the Life Celsius water project is to: Save energy in purification processes, reduce greenhouse gases and eliminate the greater amount of organic matter and nutrients from wastewater.
An initiative backed by the European Union
The Waste Water Treatment Plant (WWTP) in Archena (Murcia) will show until 2018, that it has been implemented under the premises of less consumption, greater production, no pollution as in addition, its efficiency in warm climate areas.
The project, co-financed by the European Life programme, in which participates the EFE News Agency, is a combination process which firstly removes organic matter in an anaerobic bioreactor membrane and then removes nitrogen using Anammox bacteria.
The first stage is the result of the OptiAnMBR project, already operational. The latter is supported by the Ministerio de Economía y Competitividad (Ministry of economy and competitiveness) and developed by Acciona Agua, Esamur (The Entity for Water Cleansing and Sanitation of Murcia) and Cetenma (Technological Center for Energy and the Environment).
The biggest advantages of this first phase are, on the one hand, that the bacteria responsible for degrading the organic material may do so without the need of an external heat source and this reduces the energy needs of the process.
On the other hand, that those microorganisms do not require oxygen for their metabolic functions, which reduces aeration requirements and in addition, they generate biogas, which can be used as fuel.
María del Mar Micó, chemical engineering from Acciona Agua and Director of the project explained to EFE that aeration is used in conventional treatments to oxygenate the bacteria and is “one of the processes that consume more energy” in a WWTP (Waste Water Treatment Plant).
María del Mar continues explaining that, in addition, since it does not require a source of carbon, necessary in some cases for the removal of nitrogen in aerobic reactors, the new system “will allow greater energy savings”.
María del Mar Micó explains that in a second phase, Life Celsius will install a system that, with limited ventilation, will remove nitrogenous nutrients transforming them into nitrogen gas which is, “the main component of the air we breathe”.
The combination of both stages will save 60 percent of the energy required in the main processes of wastewater treatment, that will result in a significant decrease of greenhouse gas emissions.
Gloria Gómez, Technician of Acciona Agua, is responsible for the maintenance and control of the pilot plant and oversees the characteristic parameters of the effluents, energy consumption and the quality of the biogas produced.
“The Life Celsius project is intended to develop and test a waste water treatment system in warm climates”, for which a treatment plant has been chosen “where the average ambient temperature is around 19 degrees Celsius”.
María del Mar points out that this technology will enable us, “to obtain safe water for reuse, with lower energy cost than conventional treatments, a very interesting option in areas such as the Region of Murcia, in which water is a very scarce”.
According to María del Mar Micó, the challenge will be to maintain an adequate biomass activity, despite working at room temperature and not with external heating.
María del Mar explains that “we need the effluent coming as residual water to be around 15 to 25 degrees centigrade” and this is possible in parts of the Mediterranean basin, Africa, Latin America or India “which are precisely places with problems of eutrophication (increased nutrients in surface waters) and water stress”.
Life Celsius Project Director has explained that the resulting water of the purification process carried out at the WWTP of Archena is poured to the Segura River with excellent quality; in fact, “it is expected to exceed 90 percent of removal of organic matter and the same percentage of nitrogen compounds”.
And if nutrients were not eliminated, if it still contained any nitrogen and phosphorus, it could even be reused for irrigation, where “it would act as a fertilizer”.
However, she continues saying: “we cannot stop there, because if the water is poured to the environment with nitrogen content, it could generate problems of eutrophication and hypoxia in surface water masses”.
Traducción: Carmen Gilson