Brewery Waste Biochar Traps Bacteria in Filters

Researchers at the University of Patras have found that biochar made from a common brewery byproduct can substantially improve the ability of sand to retain Escherichia coli, pointing to a potential new use for brewing waste in water filtration and groundwater protection.

In laboratory column experiments, sand amended with 10% biochar removed 94.1% of E. coli, compared with only 17.8% removal by unamended sand. The study also revealed that adding more biochar changed how the bacteria were retained, shifting the dominant process from simple physical trapping to direct attachment to the biochar surface.