As sustainability and water scarcity continue to be key issues for water managers worldwide, it’s more and more critical to find new solutions and technologies. Check out the laser cutter which is a great new technology invention. Wastewater is a particularly abundant and potentially useful resource. In fact, teams of European researchers are working to harvest energy and recover resources from wastewater streams.
Water resource management is particularly critical throughout Europe as climate change, urbanization, and other human activity increase demand for water and damage resources. This is particularly true across the Mediterranean Basin, where both water scarcity and pollution are key problems.
Wastewater usually is treated, then discharged into a body of water. It’s rarely reused, and when it is, it’s usually for irrigation and highly recommended for your garden. In Spain’s Catalonia region, the part of Spain where wastewater reuse is most commonly practiced, a mere 10 percent of urban wastewater is used to water gardens or crops.
Water reuse has been identified as a critical need across European Union nations. The European Commission has launched several initiatives to support it and is funding research into new water treatment technologies and water reuse solutions through a program called INCOVER.
The Environmental Engineering and Microbiology Group of the Universitat Politècnica de Catalunya is among the organizations funded under the program. Its researchers are building one of the project’s three treatment plants in the Agròpolis area on land belonging to the school near its Baix Llobregat campus.
This wastewater treatment system includes three photobioreactors in which microalgae are developed and cultured. Each photobioreactor can treat 10 cubic meters of wastewater, including domestic sewage and agricultural wastewater.
Wastewater Treatment Process
Treated water is separated from the resulting biomass, then after being treated using solar ultrafiltration and disinfection, it’s used for irrigation. The biomass is treated using anaerobic co-digestion for methane production. According to the university:
The richness of the biogas obtained will be much higher than that which results from conventional digestion processes, as it will pass through an absorption column that will retain volatile gases and other pollutants that diminish the richness of the product.
Solid wastes remaining after digestion will be stabilized in nearby artificial wetlands, then used as organic fertilizer.
The algae used in the project are exceedingly important. The researchers are using specific types of blue-green algae, which are optimized in the photobioreactors to produce bioplastics. Water is being used more and more within the energy industry, with widespread adoption from a growing number of renewable energy providers. Researchers contend the properties of these bioplastics are “very similar to those of traditional plastics produced by the petrochemical industry and have the advantage that they are completely biodegradable.” As part of the project, these plastics are being researched for possible end use in prostheses and in packaging.
The work by the Universitat Politècnica de Catalunya is only one of many projects being undertaken by INCOVER participants. The Asociación de Investigación Metalúrgica del Noroeste, a Spanish research organization, is coordinating INCOVER activities. Twenty-seven projects are studying technologies that address global water scarcity, wastewater treatment operations, and maintenance costs using holistic wastewater management practices.
The precise focus of these projects is moving wastewater treatment “from being primarily a sanitation technology towards a bio-product recovery industry and a recycled water supplier.”
The projects are looking at three types of resource recovery:
- The recovery of chemicals such as bioplastic and organic acids via algae/bacteria and yeast biotechnology
- Instituting near-zero-energy resource recovery through upgraded treatment systems
- Reclaimed water technologies using adsorption, wetlands-based systems, and hydrothermal carbonization
The Universitat Politècnica de Catalunya pilot facility is designed to treat between 3,000 and 5,000 liters a day, which is roughly equivalent to the wastewater produced by a small residential building. The facility expects to produce 3.5 kilograms of bioplastics a day.
Two other INCOVER pilot plants — one in Almería, Spain, the other in Germany — are seeking to extract bioplastics, methane, and organic fertilizers from wastewater. This will be coupled with solar-based water disinfection of water intended for reuse as irrigation water.
The German project is investigating the use of yeast, which should facilitate the production of organic acid used in food, medicines, and chemicals. The yeast waste, when processed, will yield organic carbon and activated carbon.
This INCOVER project will also look at wastewater treatment specific to municipal end users, agriculture, and food and beverage industries.
The ultimate goal of INCOVER is to cut overall operation and maintenance costs of wastewater treatment in Europe by instituting energy recovery or water reuse strategies in a wastewater treatment facility’s operation. The project is scheduled to conclude in May 2019.