Conversion of biosolid to value added biochar via pyrolysis technology for PFAS elimination

Per- and polyfluoroalkyl substances (PFAS) are a very large family of persistent anthropogenic chemicals utilized in the manufacturing of industrial materials with non-stick and oil/water repellent properties, Teflon, and fire-fighting foams. Their use has resulted in their final dispersion in soil, groundwater, and surface water, causing adverse environmental and health effects. They are responsible for serious environmental and human-health issues, including cancer, liver damage, cardiovascular problems, birth defect, and immune system disorders. They are often concentrated in the biosolids generated in wastewater treatment processes. This proposal is composed of two stages. Firstly, the effect of high temperature pyrolysis technology (HTP) on the destruction of PFAS in biosolids is investigated. Pyrolysis processes generate three products: non-condensable gas, biooil, and biochar. The fate of PFAS is investigated by analysis of all the three products. Our preliminary results indicate that the measured detectable PFAS in the biochar product is reduced by 97-100 wt% at a processing temperature of 500°C, and by 99.6-100 wt% at 700°C. Considering all product streams (biochar, biooil and non-condensable gas), the measured PFAS is reduced by 88.2 wt% at 700°C.

Faculty Supervisor:

Franco Berruti

Student:

Partner:

CHAR Technologies

Discipline:

Engineering

Sector:

Manufacturing

University:

The University of Western Ontario

Program: