| Attachment | Size |
|---|---|
| 18_Hernandez_NABBC_Submitted.pdf | 2.89 MB |
Comparative assessment of biochar materials produced from common organic waste feedstocks at laboratory and commercial scales
Biochar is widely recognized for its various commercial applications and carbon sequestration potential, but most available physicochemical properties data are based on materials produced at laboratory scale under precisely controlled conditions. To develop thermochemical conversion as a viable organic waste valorization technology, there is a compelling need to characterize biochar made using commercial scale equipment operated under “real world” conditions. In this study, we produced biochar from widely available organic waste feedstocks, including mixed cafeteria food waste, blended coffee grounds and chaff, and grape pomace, using both a laboratory furnace operated in nitrogen environment and a continuously operated commercial system capable of processing up to 1 t/day of dry feedstock. Proximate analysis, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to assess the differences in properties of biochar made at lab and commercial scales. High quality biochar was obtained for all feedstocks (H:C > 0.7), however high variability in volatiles and decomposition rates was seen in the TGA results for commercial biochar. SEM and FTIR showed similar morphologies and surface chemistries in both lab and commercial scale samples, in agreement with reported literature data. Based on this initial comparative assessment, we conclude that commercially available thermochemical systems have potential as localized organic waste valorization technologies to produce high quality biochar. The fundamental characteristic of some commercial scale produced biochars lack the homogeneity observed in laboratory samples. Despite this variability, key properties critical for soil amendment and remediation applications (H:C, pH, surface area, etc.) are generally maintained.
Keywords: commercial biocharhydrogen-to-carbon ratiothermogravimetric analysisscanning electron microscopyFourier transform infrared spectroscopysurface area
Yvan Hernandez-Charpak
Madan Manipati
Carlos Diaz
Thomas Trabold
Rochester Institute of Technology, Rochester, NY, United States