A geotechnical perspective on carbon sequestration in clay using gasifier biochar

• Main Author: Williams, James Michael
• Other Authors: Farshid Vahedifard
• Format: Others
• Language: en
• Published: MSSTATE 2018
• Subjects: Civil and Environmental Engineering
• Online Access: http://sun.library.msstate.edu/ETD-db/theses/available/etd-06252018-214229/

There is a growing need for employing sustainable soil improvement techniques. Concurrently, soil carbon sequestration methods continue to receive more attention in an attempt to reduce greenhouse gas levels contributing to climate change. Exploring the use of gasifier biochar for soil improvement can possibility address these two needs simultaneously. This study investigates the effect of gasifier biochar amendment on mechanical, chemical and hydraulic properties of a local clay with poor engineering properties. Specifically, strength, swelling, compressibility, collapsibility, permeability, water retention, cation exchange capacity, pH, and microstructural characteristics were determined for the clay amended with 5, 10, and 20% biochar. Two sizes of biochar were used. The results showed that biochar amendment improves the strength, swelling potential, permeability, and water retention properties of the clay. Findings suggest that biochar amendment offers a sustainable solution for improving geotechnical properties of marginal soils while providing an efficient method for biospheric carbon sequestration.