“Switching to Filtralite is a seamless process bringing both technical and operational benefits"
Filtralite is proud to present an interview with Geir Norden, R&D specialist, and Jaran Wood, Environmental Manager, about how Filtralite helps to decrease CO2 emissions during the filtration stage in drinking water and wastewater plants, but also in pre-treatment for desalination. They highlight how Filtralite will help to improve plant performance, due to its high porosity, low weight, and unbeatable longevity.
What is the main advantage of Filtralite compared to sand from a filtration and environmental perspective?
Geir Norden: The main advantage of Filtralite compared to sand lies in several key aspects of both filtration and environmental impact. Filtralite has a high retention capacity, which results in longer filter runs and less frequent backwashing. This not only reduces water wastage by minimizing the need for withdrawals from the natural environment, but also lowers energy consumption.
Filtralite’s high porosity and specific surface area enhance filtration efficiency, enabling it to capture more contaminants than sand
Its high porosity and specific surface area further enhance filtration efficiency, enabling Filtralite to capture more contaminants than sand. The low density of Filtralite allows for quick expansion during backwash, making the cleaning process more efficient.
Jaran Wood: Additionally, Filtralite enables high water filtration velocity, thus requiring fewer filters and smaller plant sizes, potentially reducing infrastructure requirements by up to 50%. This translates into a significantly lower carbon footprint and reduced environmental impact compared to sand-based filtration systems.
Are there additional benefits?
J.W.: Yes, there are additional benefits of using Filtralite compared to sand, particularly in terms of both operational and capital expenditure (OPEX and CAPEX).
In terms of OPEX, Filtralite reduces energy consumption due to its efficient filtration properties, which require less energy for backwashing. Additionally, the need for fewer backwashes results in reduced water consumption, further lowering operational costs.
From a CAPEX perspective, Filtralite leads to cost savings by requiring smaller pumps and other equipment, thanks to its high retention capacity and porosity. This reduces the need for larger infrastructure, thereby lowering capital investment costs.
G.N.: Furthermore, Filtralite’s ability to extend filter runs and reduce backwashing enables the construction of more compact plants, which results in smaller facilities with reduced overall costs. The higher operational efficiency also leads to increased production capacity and a better return on investment, making Filtralite a more cost-effective option compared to sand.
What are the primary sources of CO2 emissions in the current sand filtration process?
In terms of OPEX, Filtralite reduces energy consumption due to its efficient filtration properties, which require less energy for backwashing
J.W.: The primary sources of CO2 emissions in the current sand filtration process stem from several stages of the sand's lifecycle. First, the extraction of sand involves significant energy consumption, as it requires large-scale mining operations, often using heavy machinery that emits CO2. Second, transporting the sand to filtration facilities generates additional emissions, particularly since sand is much heavier than alternatives like Filtralite, increasing the carbon footprint associated with its transport.
Another factor contributing to CO2 emissions is the depletion of sand resources worldwide. As easily accessible sources become scarce, more energy-intensive extraction methods are required, further exacerbating environmental impact. In contrast, Filtralite, with its lighter weight, helps reduce transport-related emissions and is more sustainable as a resource, addressing some of the challenges posed by diminishing sand availability.
How do Filtralite’s emissions compare to sand?
G.N.: Despite the higher CO2 emissions during production, the weight of the sand has even larger impacts, including the need for stronger backwashes, which require more power and thus bigger pumps, with more frequent backwash and a larger filtration area.
From a CAPEX perspective, Filtralite leads to cost savings by requiring smaller pumps and other equipment, lowering capital investment costs
J.W.: In addition, the clay resources compared to filtration sand are close to unlimited, and even more, with 1 m3 of raw clay, we are producing 5 m3 of finished product.
How does the lifespan of Filtralite compare to sand in terms of reducing material replacement and associated emissions?
J.W.: The lifespan of Filtralite is significantly longer compared to sand, which contributes to reducing material replacement and associated emissions over time. While Filtralite may have a higher initial carbon footprint due to its production process, the longer lifespan more than compensates for this in the mid to long term.
Filtralite results in lower CO2 emissions in the mid-term, as it reduces both operational and material-related impacts over time
Filtralite typically lasts around 30 years, whereas sand generally has a lifespan of 15 to 20 years. Other materials, like anthracite, can last even less, often between 2 to 10 years. This longer longevity means that Filtralite does not need to be replaced as frequently, reducing the amount of material required over time and consequently lowering the CO2 emissions associated with material replacement and transportation.
After approximately two years, the energy and water savings resulting from Filtralite's higher filtration efficiency and reduced backwashing start to outweigh the initial CO2 emissions. Over time, these operational savings — combined with Filtralite’s durability — lead to a net reduction in CO2 emissions.
G.N.: In fact, the first Filtralite produced 30 years ago is still in operation, demonstrating its remarkable longevity and further emphasizing the environmental benefits of reduced material replacement. Thus, while Filtralite may initially have a higher environmental impact, its extended lifespan and greater operational efficiency lead to significant savings in both energy and CO2 emissions.
Does Filtralite require less frequent maintenance, and how does that affect overall emissions?
G.N.: You have to change the filter media less often, meaning less maintenance of the filters. Also, there is less need for new filter material, and thus less transport and less extraction.
Does using Filtralite impact energy consumption during the filtration process? If so, how?
J.W.: Yes, Filtralite requires less maintenance compared to sand due to its higher efficiency and longer lifespan. This leads to reduced energy use for backwashing and fewer media replacements, cutting down on transportation emissions and the need for raw material extraction. Overall, Filtralite results in lower CO2 emissions in the mid-term, as it reduces both operational and material-related impacts over time.
How do transportation distances and methods contribute to differences in CO2 emissions?
G.N.: Transportation distances and methods contribute to differences in CO2 emissions by making Filtralite more efficient to transport than sand. Filtralite's lighter weight allows trucks to be fully loaded, whereas sand trucks may be only 1/4 full due to weight limits, requiring more trips and increasing emissions. Sand is not always locally available, meaning it often needs to be transported over long distances, which adds to CO2 emissions. Filtralite, however, promotes intermodal, efficient transportation methods (like rail or ships) to further reduce its environmental footprint.
How does better performance (if applicable) translate to environmental benefits, like reduced chemical usage?
J.W.: Better performance, like Filtralite's high filtration efficiency, can translate into significant environmental benefits, including reduced chemical usage. For example, Filtralite can replace certain chemicals used in traditional filtration processes by supporting biofiltration in drinking water treatment. This is particularly beneficial for removing contaminants like manganese and iron. By reducing the need for chemical treatments, Filtralite helps minimize chemical waste, energy consumption, and environmental pollution, leading to a more sustainable water treatment process.
Are there any technical or logistical challenges when switching from sand to Filtralite?
G.N.: There are no challenges when switching from sand to Filtralite. In terms of retrofitting existing plants, the increase in pollutants and organic matter in the water due to climate change and human activities makes Filtralite a better choice, as it handles these contaminants more effectively. When you upgrade from sand to Filtralite, the transition is straightforward, and the switch comes with direct advantages like improved filtration efficiency and longer lifespan. Overall, switching to Filtralite is a seamless process that brings both technical and operational benefits.
Are there any certifications or standards that validate Filtralite’s environmental claims?
Filtralite, with its lighter weight, helps reduce transport-related emissions and is a more sustainable resource than sand
J.W.: Yes, Filtralite's environmental claims are validated through several recognized certifications and standards. Specifically, ISO 14001 (Environmental Management) and ISO 9001 (Quality Management) are in place, ensuring that Filtralite meets rigorous environmental and quality standards, and in the future, we may be able to provide project specific EPDs for the filter medium. Also, to ensure the best water quality, we submit the filter medium to stringent tests for all types of contaminants through certified third parties.
Additionally, Saint-Gobain is committed to reducing CO2 emissions by 2050, reflecting their dedication to sustainability. The company also has a strong commitment to social responsibility, further reinforcing the environmental and ethical benefits of using Filtralite.
These certifications and commitments validate Filtralite’s environmental impact and demonstrate its alignment with global sustainability goals and Saint-Gobain's goal to "make the world a better home".