How blankets based on rice straw and sugar cane are slowing soil erosion

Échantillon de produits issus du projet de recherche BioMatUse : tapis anti-érosion, granulés d’engrais et de charbon actif.

View of all the materials available by recycling rice straw and sugar cane residues. - CREDIT PHOTO: TU Bergakademie Freiberg

Rice and sugar cane cultivation produces a lot of waste, which is usually destroyed on site or sent to landfill. However, German and Vietnamese scientists have just found new uses for these byproducts: they wove mats from rice straw and sugar cane residues and placed them on an embankment in the city of Freiberg in Saxony, Germany. 

Natural mats of this type are already used in the province of Thanh Hoa, Vietnam, to combat erosion and enrich the soil in nutrients. The roots of the plants sown under these mats end up forming a network that stabilizes the soil in the long term through the decomposition of the mats. 

“These erosion control mats are very suitable for preventing surface erosion by rain and wind,” explains Volker Herdegen, who heads the team of engineers behind this study at the Institute of Thermal, Environmental and Resources’ Process Engineering at the University of Freiberg.

Rice straw and sugar cane residues could be a good replacement for the coconut fibers currently used to make mats. A blanket woven with these materials decomposes in a year to a year and a half, compared to three years for a coconut fiber mat.

This biomass recycling solution therefore opens up new economic opportunities for rice and sugar cane producers in emerging countries. 

Improving soils and purifying water

Rice straw and sugar cane waste can also be used to improve soils, as demonstrated by BioMatUse, another research project from the same team. In this project, scientists ground the waste and turned it into pellets that release their nutrients into the soil over a longer period. 

Then, by burning the pellets by pyrolysis, in other words in an oxygen-free atmosphere, the researchers obtained activated carbon that can absorb the pollutants found in water and air. This new renewable material could be a good replacement for the fossil raw materials used to purify water in emerging countries. 

The results of the research into these new methods were published in the November edition of the journal Chemie Ingenieur Technik.

SOURCE :

A Concept for an Integrated Process Scheme for By‐Products from Rice and Sugarcane Processing, Chemie Ingenieur Technik, November 13, 2020 - onlinelibrary.wiley.com/doi/full/10.1002/cite.202000088?af=R+

Using residues from rice and sugar cane production to develop new sustainable products, TU Bergakademie Freiberg, November 10, 2020 - tu-freiberg.de/en/department-52-media-relations/using-residues-from-rice-and-sugar-cane-production-to-develop-new-sust