Can tomato plant waste be repurposed into agricultural fertilizer? Yes, it can. But how can you optimally recover the plant waste's nutrients and energy? That question is at the heart of the new Tombustion research project, which started this month.
Fertilizer prices have skyrocketed in recent years. This is also not the only challenge the sector faces. "Producing fertilizers isn't environmentally friendly and requires a lot of energy. Essential mineral fertilizers' raw materials are finite and irreplaceable," says Josephine Cafmeyer of Anorel.
This Belgian company produces and distributes fertilizers and initiated this project. "Changing legislation aimed at more sustainable agriculture also restricts where fertilizers can be used. And then there's growers' residual waste, a stream that isn't optimally utilized."
Given these challenges, there is a growing demand for green, circular fertilizer. To meet this demand, Anorel has devised an innovative concept - Tombustion. It recovers mineral fertilizer from tomato plant waste.
Tombustion, in partnership with Gent University, completed and submitted a research project to Vlaio, the Agency for Innovation and Enterprise, in 2021. In early May 2022, the project was approved, and this month, the development of this promising concept into an optimal production process began. "Tombustion is a terrific addition to our campaign of making Anorel a socially responsible, sustainable organization," says Josephine.
"During the Tombustion research project, we want to learn about recouping monocalcium phosphate from tomato plant waste as energy-neutrally as possible."
The company chose tomato plant waste as its fertilizer's raw material. "Belgium and the Netherlands use about 2,400 hectares for growing tomatoes and almost exclusively hydroponically. Biomass grown in this way benefits from having a very uniform composition because of the tight fertilization schedule."
"Also, heavy metals or other contaminants absorption can be excluded since the plants aren't grown in full soil, but on substrate. That makes hydroponic tomatoes an interesting crop from which biomass to recover nutrients," Josephine concludes.