All sectors need water, including the industrial sector. There are fewer and fewer water resources but demand continues to grow. How do we get more water available? “The concept of circular economy is interesting because we must adapt to the new situation, but we can do it from circularity. The first thing we have to do is plan the infrastructure well and make the best possible use of water, which means greater savings and efficiency,” explains Miquel Rovira, director of Eurecat’s Sustainability area.
From the technology center they work with the industrial sector to find new strategies for saving water. “With the drought, industries are asked to reduce their water consumption by 20% and that can sometimes only be achieved by stopping working one day a week,” Rovira recalls. But there are practices and technology to achieve this without having to lower production. “To optimize the amount of water an industry uses, the first thing is to do an audit. Companies must know how much water they use, what quality, how and in what processes, and from here they have a first opportunity to introduce improvements,” adds the expert.
“Water can be monitored and automated to use the necessary amount within a process. It is also important to do proper maintenance to prevent leaks. And educate the workers. It is a set of good practices and concrete investments that will allow us to reduce consumption,” explains Rovira. From here, there is the possibility of recycling water. “You can use it in a cascade, because high quality water is not always necessary. “There are multiple waters for multiple uses.” Rovira gives the example of an industrial laundry, where the first rinses do not have to be with quality water like tap water.
Furthermore, “there are technologies today that allow us to close the water circuit before going to the treatment plant, it is the Zero Liquid Discharge (ZLD) concept that is used in very energy-intensive industries such as paper, the chemical sector or in mining. The idea is to close the water circuit and aim for zero discharge,” he explains. This means that after using the water, it can be treated and introduced back into the process, “which means that the company does not have to discharge water and must capture very little.” From good practices to radically closing the water cycle, there are a number of actions that can be done, such as reuse. This is the case of the Tarragona Petrochemical Complex, the largest in southern Europe, which of the total water it consumes, 20% is already regenerated and comes from the Vila-seca and Salou treatment plants. “An additional treatment is done and they use it for an industrial process,” explains Rovira.
Furthermore, in Tarragona, the companies joined together to manage water jointly and not compete with each other. Now, the management company, Aitasa, is building a new plant for all the resort’s wastewater, which “in a few years should allow water reuse to go from the current 20% to 40%, which gives the complex sovereignty and a resilience to brutal climate change,” Rovira reflects. On the other hand, “wastewater has the advantage that it can have energy embedded in the form of organic matter and, many times, it has nutrients or materials with added value. That’s why I say that wastewater is a source of resources: you get water, energy and materials that you can recover. We are returning to the circular economy,” concludes the Eurecat expert.
