# Carbon Footprint Assessment on the Viability of Utilizing Brewer's Spent Grain to Produce Biochar
## 4 Discussion
### Future Considerations  
The major factor that contributed to the GWP of this process was the electricity used in the pyrolysis step. It is presumed that employing larger-scale and more energy-efficient pyrolysis equipment would lead to a significant decrease in emissions. This straightforward modification would render the process more sustainable. Therefore, future studies should prioritize the implementation of this biochar production method on a larger scale to gather more robust and reliable data. To mitigate the negative environmental impacts of the energy required for pyrolysis, the utilization of sustainable forms of electricity (e.g., solar panels, syngas from anaerobic digestion, recovered steam from the brewery) would be beneficial. Additionally, during the soaking phase, BSG could be left to soak in a ventilated area that is more energy-efficient, as the fume hood used in this scenario consumed a substantial amount of energy, contributing significantly to GHG emissions. While the electricity demand for oven usage was relatively small compared to pyrolysis and ventilation, it still contributed to overall emissions. Therefore, the adoption of a more energy-efficient oven or the use of sustainable forms of electricity would also be advantageous in this regard. Conceptualization, E.N., N.N., E.S. and G.F.; Methodology, E.N., N.N., E.S. and G.F.; Formal analysis, E.N. ; Investigation, E.N. and G.F.; Resources, G.F.; Data curation, E.N. ; Writing--original draft, E.N. ; Writing--review & editing, E.N., N.N., E.S. and G.F.; Visualization, E.N. ; Supervision, N.N., E.S. and G.F.; Funding acquisition, G.F., N.N., and E.S. All authors have read and agreed to the published version of the manuscript. Nitin N was supported by U.S. Department of Agriculture Natural Resources Conservation Service (USDA-NRCS) award #NR243A750004G028. Spang E was supported by U.S. National Science Foundation (NSF) award #2115405. Not applicable. N.N. * [PERSON] and [PERSON] (2016) [PERSON]; [PERSON] Sustainable mechanisms of biochar derived from brewers' spent grain and sewage sludge for ammonia-nitrogen capture. _J. Clean. Prod._**2016**, _112_, 3927-3934. [CrossRef]
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