Source: PHYS ORG
According to a recent scientific article, this research has progressed to a stage where it is ready for industrial production and practical application. The findings are published in the journal Current Opinion in Biotechnology.
Professor Per Halkjær Nielsen from the Department of Chemistry and Bioscience at Aalborg University in Denmark comments on the outcomes of a research project aimed at repurposing surplus biomass in innovative ways. The main focus is on biopolymers, which are essentially long chains of molecules produced by living organisms, including bacteria.
The perspective is enormous, because you're taking something that is currently waste and making high-value products from it.
Currently, synthetic polymers are manufactured in the petrochemical industry using crude oil and are utilized in various applications such as plastics, textile fibers, adhesives, and paints. However, the future production of biopolymers at wastewater treatment facilities could provide a sustainable alternative to these oil-based polymers by utilizing waste products.
Biopolymers have several applications, serving as binding agents in paper and building materials, and they can also be utilized for flocculation, where small particles aggregate and settle during water purification processes in harbor sludge, lakes, and treatment plants. An additional advantage is that biopolymers from wastewater treatment facilities appear to be fire-retardant. Therefore, if commercially produced sustainably, there is significant market potential for biopolymers, as indicated by the REThiNk research project.
In short, the work on biopolymers is about producing a lot of biomass in wastewater treatment plants that is actually bacteria that eat everything that enters the treatment plant so that only the pure water remains. Every single day, many tons of biomass are produced, depending on how big the treatment plant is, and this is typically converted in a biogas reactor so that you get energy out of it. A large part of the bacteria consists of biopolymers, i.e. the adhesive material around them, and biopolymers are in demand in the industry as a sustainable alternative to oil-based polymers.
Wastewater treatment plants host hundreds of different bacterial species that produce various types of biopolymers with distinct properties. These bacteria utilize the biopolymers as adhesives to form colonies and adhere to surfaces, preventing them from being washed away.
By altering the pH and temperature of the water, these biopolymers can be extracted to produce cellulose and gelatinous substances suitable for various industrial applications. The goal is to establish factories in Denmark that generate biopolymers from local wastewater treatment plants, given the immense potential, as hundreds of thousands of tons of bacteria are produced annually in the country.
There is great potential if companies can see that the product can be used for something and thus want to invest in testing and developing it. And this requires that we build pilot scale plants so that we can produce not just grams, but kilograms and in a few years' time many tons. We can take 20–30 percent of the biomass and turn it into biopolymers that can replace petroleum products, but it actually also replaces seaweed. Today, many biopolymers are produced from seaweed from large kelp forests that are endangered. So if we can find other ways to extract biopolymers, it is a clear advantage for the environment and biodiversity as well
Moreover, valuable minerals and components can be harvested from the incoming wastewater, including phosphorus, which is listed as a critical raw material by the EU and may become scarce in the future.
The REThiNk project's objective is to lay the groundwork for industrial-scale operations in the near future, aiming for a genuine revolution in the recycling of biomass from wastewater treatment facilities globally, not just in Denmark. This endeavor also involves mapping the bacterial populations in treatment plants worldwide to better understand their potential roles in biopolymer production and phosphorus extraction.
Aalborg University is collaborating with Delft University in the Netherlands and Aarhus University as part of the REThiNk project.
