Sustainable plastic waste management: New insect-based bioconversion system shows promise

A team of researchers from the University of Castilla-La Mancha (Spain) and the University of Newcastle (Australia) has introduced a novel, two-stage bioconversion system that uses insect larvae to transform plastic waste into valuable by-products, offering a sustainable solution to two global environmental challenges—plastic pollution and organic waste management.

In the first stage of the system, mealworm larvae (Tenebrio molitor) are fed plastic-rich diets, resulting in frass (larval excrement) containing microplastics. This frass undergoes pyrolysis, a thermal process that converts it into biochar, a carbon-rich material with excellent pollutant adsorption capabilities. In the second stage, the biochar is incorporated into the entomocomposting process, where black soldier fly larvae (Hermetia illucens) decompose organic waste such as food scraps. The end product, termed “frasschar,” is a nutrient-dense soil amendment enriched with carbon and nitrogen, making it a valuable resource for agricultural applications.

“This innovative system is based on the principles of ecotechnology, integrating insect-based bioconversion with advanced pyrolysis techniques to create a circular solution for managing plastic and organic waste while producing value-added products,” explained lead researcher Juan C. Sanchez-Hernandez. “By producing nutrient-rich compost enriched with biochar, we’re addressing waste issues while contributing to soil health improvement.”

The proposed approach has significant potential for large-scale adoption in industries focused on sustainable waste management. Further research will explore ways to optimize efficiency, scale up operations, and evaluate environmental safety.