Crystallization nuclei obtained from biowaste enables the production of concrete in accordance with the principles of circular economy

Abstract

Concrete production is material and energy demanding making it the third largest source of anthropogenic pollution. It was hypothesized that fermentation residues will be (1) dewatered; (2) charred; (3) activated; (4) applied to sorb P from wastewater; and (5) the resulting substrate will be used as a cement substitute. It is firstly reported that the mixture of phosphates captured on the char tends to form crystallization nuclei that tend to increase the strength characteristics of concrete (compressive strength + 9 %; modulus of rupture + 13% and modulus of elasticity +16%), while at the same time making it lighter and less costly. Despite this mutual valorization of waste between each other has proven technologically feasible and fully in accordance with the concept of circular economy, it should be noted that there are no established buyer-supplier chains for this technology. © 2022 University of Split, FESB.