Is Pyrolysis Treatment a Viable Solution to Detoxify Metal(loid)s in Sewage Sludge toward Land Application? Case Studies of Chromium and Zinc

What is it about?

Converting SS into biochar via pyrolysis has recently gained intensive attention due to its merits of significantly reducing sludge volume, decomposing pathogens and organic pollutants, promoting carbon sequestration and metal(loid) immobilization (i.e., decreasing their availability). Nevertheless, metal(loid)s in SS-derived biochar (SSB) after pyrolysis are usually significantly concentrated, which makes pyrolysis an attractive but potentially problematic treatment for SS. Our study characterized the speciation and bioavailability transformation of typical SSB-borne metal(loid)s during aging in soil, and explored the underlying mechanisms and the controlling factors for the translocation and uptake of the metal(loid)s from soil to plant.

Featured Image

Why is it important?

The findings of this study would be critical to comprehensively assess the stability and risks of immobilized metal(loid)s in organic wastes induced by pyrolysis and thus the viability of large-scale application of organic waste-derived biochar to soil.