Recently, they are beginning to proliferate diverse uses of renewable energies for very useful activities, such as wastewater treatment. Renewable energies have the potential to completely transform the way we manage water waste at industrial and domestic levels.
Among emerging technologies, Solar energy stands out in the treatment of industrial wastewater, offering a sustainable and efficient opportunity. There are different approaches that combine solar energy with advanced treatment processes such as photocatalysis and photodisinfection. These methods not only remove contaminants but also allow the energy savings, greater efficiency and lower environmental impact.
Pioneering scientific projects
At the University of Almería, a study is being carried out on the solar energy wastewater treatment, focused on the disinfection and decontamination of industrial waters. The project, led by Professor Jose Luis Casas Lopez, uses innovative processes including activated sludge and membranes in combination with solar energy.
This process is complex, and in its third phase the use of photocatalysis as a method for degrading pollutants. According to the study, “pollutant degradation occurs by hydroxyl radicals generated in the photocatalytic oxidation/reduction cycle of iron.” This type of research is not only innovative, but also represents a viable solution in ecological and economic terms for managing water waste.
How photocatalysis works in water treatment
La photocatalysis It is a process that uses sunlight to generate chemical reactions that break down contaminants present in water. This is achieved through the action of catalysts such as titanium dioxide (TiO2) and iron, which when exposed to UV radiation, generate highly oxidizing radicals such as hydroxyl radical (OH·). These radicals are responsible for oxidizing and breaking down polluting molecules, transforming them into less harmful substances such as carbon dioxide and water.
A clear example of this is the work of the Institute of Renewable Energies, where the toxicity of waste water has been reduced by up to 90%. by this method. Hydroxyl radicals play a key role in breaking down complex and hazardous organic compounds such as pesticides, drugs and industrial chemicals.
Challenges and advances in the degradation of emerging contaminants
In the context of wastewater treatment, many studies focus on removing emerging contaminants, such as pharmaceutical, cosmetic and pesticide residues, which are difficult to remove with conventional treatments. Polytechnic University of Madrid developed an innovative compact photoreactor that combines electrochemical oxidation with photocatalysis to attack these pollutants. This reactor uses TiO2 nanotubes, together with sunlight or LEDs, to break down difficult-to-treat molecules.
These types of pollutants are known as “emerging concern”, as they can cause endocrine and neuronal system disorders, hormonal disruptions and even several types of cancer, according to recent studies. Many of these are persistent and are not completely eliminated in current water treatment processes, making them a priority focus for research.
Featured projects in Latin America and their impact on drought
Chile has been one of the countries most affected by water crises in recent years. In response to this problem, a team led by the Andres Bello University has developed a pilot system for treating grey water using solar energy. Preliminary results indicate that up to 80% of pollutants can be eliminated, allowing the treated water to be reused for irrigation and other industrial uses.
These projects seek to optimize the use of alternative sources of water, avoiding overexploitation of natural sources and adapting to the needs of the population, especially in rural areas. The main innovation lies in the use of modified clays and titanium dioxide for activation in the presence of sunlight, making the treatment more efficient and environmentally friendly.
Photovoltaic solar energy for wastewater treatment
Another important advance is the use of Photovoltaic panels integrated into the process water treatment plants. These panels not only generate the power needed to run water pumps and other equipment, but also play a crucial role in some reactor designs.
This system, known as SolWat, has proven to be especially efficient in disinfecting and generating energy simultaneously. With a thin film of water Flowing over the solar panels, these devices allow the panel surface to be cooled, increasing its energy efficiency. In addition, the UV and far-infrared radiation passing through the water contributes to the disinfection of wastewater.
Implementation of pilot plants and their future
The use of pilot plants is essential to test the viability of these technologies under real conditions. These plants allow the evaluation of the efficiency of the catalysts and the operation of the equipment. industrial scaleIn Chile, for example, a pilot project funded by CORFO is underway, which has enabled the design of a self-sustaining solar-powered treatment plant.
According to the director of this project, Elizabeth Garrido, the first results suggest that it is possible to scale these technologies and apply them in different industrial sectors, from the wine industry to greywater treatment. As optimizations are achieved, these plants could implement energy-efficient pumps, making the process completely sustainable.
Environmental benefits and energy savings
The benefits of using solar energy for water treatment are multiple. Firstly, significantly reduces electricity consumption by using solar energy, which translates into economic savings and a reduction in the carbon footprint. In addition, the use of technologies such as photocatalysis manages to eliminate a greater proportion of pollutants compared to traditional systems.
Solar-powered plants also stand out as an ideal solution for rural areas or areas with limited access to the electricity grid. The treated water can not only be used for irrigation, but can also meet quality standards for use in industry or even in urban areas.
Advances in this area will make solar-powered wastewater treatment a standard practice, reducing dependence on conventional water resources and helping to mitigate problems related to water scarcity.
Projects such as those being developed at the University of Almería, the University of Jaén and the Andrés Bello University are clear examples of how innovation and technology can offer long-term solutions to environmental problems. The combination of solar energy with advanced treatment methods allows wastewater to be cleaned not only more efficiently, but also in an ecologically responsible way.