“We are moving towards more sustainable and efficient water services”
Spain's water sector is a complex and critical industry that plays a pivotal role in the country's development, sustainability, and economic prosperity. Filtralite®, the filter media solution from the Saint-Gobain group, can contribute to addressing the challenges of water scarcity, climate change, and increasing water demands.
With its diverse geography, varying water resources, and changing climate, Spain faces numerous challenges and opportunities in managing its water resources. We will try to summarize and explore the key aspects of Spain's water sector, the challenges it faces, and the strategies being employed to ensure a sustainable and efficient water supply.
Water resources are unevenly distributed throughout Spain, with the northern regions enjoying more abundant water supplies compared to the arid south and east. Managing this disparity is a fundamental challenge. The country has an extensive network of reservoirs, canals, and pipelines to distribute water to different regions.
The treatment of wastewater is a critical aspect of environmental protection. Spain has made substantial investments in wastewater treatment plants to meet European Union (EU) standards. This has not only improved water quality but also contributed to safeguarding ecosystems and public health.
Due to water scarcity in certain regions, Spain has emerged as a global leader in desalination technology. Desalination plants in places like Almeria, where you can find the Filtralite® solution, Valencia, and Catalonia have alleviated water stress. Desalination is not without challenges, particularly due to its energy-intensive nature, but it remains a vital solution for water-scarce areas.
Agriculture is the largest consumer of water in Spain, accounting for approximately 60% of the country's total water use. The challenge lies in balancing the water needs of agriculture with those of other uses. Sustainable practices like drip irrigation have been adopted to optimize water use and improve water efficiency.
Like many other regions, Spain faces the consequences of climate change. Changing precipitation patterns and rising temperatures are impacting water availability. Adaptation strategies to address increased water scarcity and droughts are becoming increasingly important.
Desalination plants in places like Almeria, where you can find the Filtralite® solution, Valencia, and Catalonia have alleviated water stress
Spain's booming tourism industry and rapid urbanization contribute to a high water demand, particularly in coastal areas. Sustainable urban planning and water management are essential to meet the needs of residents and tourists while preserving natural ecosystems.
Spain has a complex legal and regulatory framework for water management. Coordinating various government levels and ensuring compliance with EU regulations can be challenging, requiring effective governance and intergovernmental collaboration. The management of water services in Spain involves both public and private entities. Balancing efficiency, affordability, and public interest can be a challenging task, and debates about privatization persist in some regions.
Filtralite®, the filter media solution from Saint-Gobain group, has been implemented in the Llobregat DWTP in Barcelona, managed by ATL
To conclude, Spain's water sector is a multifaceted industry, critical for the country's development and sustainability. Efficient water management, technological innovation, and environmental protection are key priorities in addressing the challenges of water scarcity, climate change, and the ever-increasing demands of agriculture, tourism, and urbanization. Finding the right balance between public and private sector involvement, while preserving the environment and ensuring equitable access to clean and safe water, is an ongoing effort that is vital for Spain's future.
To help face all these challenges, Filtralite®, the filter media solution from the Saint-Gobain group, has been implemented in the Llobregat Drinking Water Treatment Plant in Barcelona, managed by publicly-owned water utility ATL. Filtralite® is made of expanded clay that is commonly used in water treatment and filtration processes. Expanded clay is a lightweight aggregate material that is produced by heating natural clay to high temperatures, causing it to expand. Filtralite®, in particular, is known for its high porosity, durability, and efficiency in water filtration applications.
We are very proud of this collaboration which is why we wanted to give Santiago Gonzalez Avellana, the Plant Manager, the possibility to share what he thinks about our products and how they help him in his daily work.
To optimize the filter run and reduce washing costs, Filtralite was tested on an industrial scale on one of the 12 filters of the plant
Can you describe your career and your current role at ATL?
I am an industrial engineer specializing in industrial chemistry and I have been working for 22 years in the drinking water treatment sector. I became part of the technical team of ATL in 2005 and I have been in charge of the Llobregat Drinking Water Treatment Plant since 2016.
Can you give us some facts and figures about your plant? What solutions did you have for the filtration stage before installing Filtralite®?
The Llobregat Drinking Water Treatment Plant was commissioned around 1978. Currently, it has a maximum production capacity of 3.2 cubic metres per second, and two very different water treatment lines. On the one hand, we have a more conventional treatment that starts with pre-oxidation of the water with potassium permanganate (KMnO4), followed by a pH adjustment with carbon dioxide (CO2) and a coagulation-flocculation-decantation process. Chlorine dioxide (ClO2) is then dosed as an oxidant and the water is passed through a double filtration stage, the first with silica sand as a filter bed and the second through a 150 cm bed of activated carbon grains.
The results showed that with the Filtralite® solution, the filtration run times were increased, reducing the number of washes by 66%
Finally, much of the filtered water goes through advanced treatment, using reverse electrodialysis membranes, prior to final disinfection and re-chlorination with sodium hypochlorite (NaClO) at the inlet and outlet of the storage tanks. The initial solution implemented to date for the filtration stage was the original one, that is, sand filtration.
How did you learn about the Filtralite® solution and what made you decide to try this innovative filtration media?
In 2017, and after the involvement of Filtralite® technicians with ATL’s research, development and innovation department, initial meetings were held to learn about the characteristics and properties of Filtralite® media. We then assessed the possibility of trying it at the plant, either on a pilot scale or on an industrial scale.
In order to optimize the filter run and reduce washing costs, we decided to carry out the test directly on an industrial scale on one of the 12 filters of the plant. Before replacing the existing sand with Filtralite®, it was necessary to adapt the filter by increasing the discharge level of the wash water. The performance of Filtralite® was evaluated by operating the filter against a sand filter under equivalent conditions for more than 10 months.
How would you describe the main features of Filtralite® and its advantages compared to your initial solution?
After almost a year of testing, the results obtained showed that with the Filtralite® solution, the filtration run times were increased, reducing the number of washes by 66%. This reduction in the number of washes translates into significant economic savings for the operations: savings in the energy consumed while at the same time, the filter operating time increases, thus increasing the treatment capacity. The reduction in the number of procedures with the equipment involved in the washing process reduces the maintenance costs of such equipment and will extend its useful life.
Finally, it should be noted that throughout the test it was possible to verify that the water quality obtained using Filtralite® was similar to that provided by sand filters, both in terms of turbidity and in terms of a barrier effect.
Did you encounter any unexpected results, positive or not, during the industrial test performed?
With the Filtralite® solution it was possible to work with higher filtration velocities than with conventional sand, even exceeding 15 m/h
Yes, we did. We were able to verify that with the Filtralite® solution, it was possible to work with higher filtration velocities than with conventional sand, even exceeding 15 m/h while maintaining part of the increase in the filtration runs.
Do you know how much energy you are saving thanks to the Filtralite® solution? What is the estimated return on your investment? Could you give us a more detailed calculation?
In the filter where Filtralite® is installed, we estimate that we are saving about 60% of energy compared to using sand. In addition, by having longer filtration runs, the reduction in the number of washes resulted in a savings of 65% of washing water. Taking these and other aspects into account, we have calculated a return on investment of approximately 2.3 years.
If you had to do it all over again, would you choose Filtralite® again? Would you recommend it to your colleagues?
Yes, indeed. In fact, tests are planned for other ATL production sites to evaluate the performance of this filtering material.
Taking into account savings in energy, washing water and other aspects, we have calculated a ROI of approximately 2.3 years
What are the next projects for your plant?
The plant's next projects are aimed at increasing the production capacity of the plant to 4 cubic metres per second. Two more decanters will be built and the 12 sand filters and the 15 activated carbon filters will be remodelled. The sand filter remodelling project includes the replacement of the sand filters with Filtralite®.
What are the characteristics of the current water market in Spain, and more specifically around Barcelona and Catalonia?
I sincerely believe that hand in hand with innovation and technological advances we are moving towards more sustainable and efficient water services, and towards treatments that allow us to obtain higher water quality. All this focused on making the best possible use of water resources that are becoming increasingly scarce.
Spain’s national government has promised a water resources action plan worth 12,000 million euros. How will this plan affect you? What do you consider to be the main areas of development?
I believe that the main areas to be developed are the increase in desalination capacity, the use of reclaimed water and the upgrading of existing treatment plants, as well as heavy investments in the digitalisation of the different processes.