Biochar-Wattle for Enhanced Surface Water Quality

Kristopher Bosch, Dr. David Hutchins, Dr. Dario Prieto, Montana Tech of the University of Montana, 1300 W Park St. 59701

Stormwater pollution is a paramount concern among rural and urban communities. However, typical active controls are often beyond the means of the disadvantaged communities where they are most needed. Instead, we propose a passive control based on a sustainable biochar-wattle design. This system consists of an outer netting that limits attrition and loss, an intermediate permeable medium that limits sediment accumulation during high flow events, and a biochar core that acts as the primary adsorbent of contaminants. The critical need in this application is an understanding of the adsorptive properties of biochar. In this study, we seek to identify the relation of biomass source and pyrolysis conditions to adsorption capacity and selectivity for copper, nitrates, and phosphates. Biochar was prepared from hemp stalk and ponderosa pinecones—abundant local waste products—heated to 600–800oC with a consistent flow of Argon. Materials were characterized by thermogravimetric analysis, scanning electron microscopy, Raman spectroscopy, and N2-physisorption using BET theory. Maximum uptake values were extracted from copper, nitrate, and phosphate adsorption isotherms using Langmuir theory. Specific surface areas of 198 ± 12 m2/g and 420 ± 18 m2/g were measured for hemp and pinecone biochar respectively. However, maximum uptakes of analytes were up to 600% larger in hemp biochar. We attribute this finding to a larger density of oxygenated functional groups as observed by Raman spectroscopy. These results demonstrate that local organic waste products can be useful for remediation and pollution management systems. Furthermore, this method of pollution prevention and management is a significant innovation in stormwater management. The biochar-wattle is potentially versatile, affordable, and easily adopted for a variety of purposes, including metal reduction in surface water, eutrophication prevention, and erosion control. 

Additional Abstract Information

Presenters: Kristopher Bosch, Sam Butcher, Amber Freebourn, Kelsey Parker, Mami Scherman

Institution: Montana Technological University

Type: Poster

Subject: Environmental Science & Sustainability

Status: Approved

Time and Location

Session: Poster 6
Date/Time: Tue 2:00pm-3:00pm
Session Number: 4648