Brewers’ spent grain (BSG) is an important waste produced in beer companies with a high po-tential to be transformed into commercial by-products. The present paper reports a forecasting technology study with the aid of bibliographic review and patent analysis tools aiming to in-vestigate the maturity of certain technologies, considering the use of BSG on a closed-loop bio-refinery and circular bioeconomy concept integrated into a brewery. To evaluate the possibili-ties of production of high-added value products in Brazil, it was presented an overview of BSG’s scientific, technological, and marketing products and applications. The comparison between numbers of articles versus patents shows that the solutions proposed by research articles are not being transformed into maturated viable technologies. The results suggest that there is a gap between the scientific research in the institutions and their applications in industry, which lead to the destination of the BSG for more economically attractive investments when compared to research in Brazil. Ultimately, from the carried-out analysis, it was possible to propose a brew-ing process connected to the biorefinery system, showing the possibility to the newly arising brewery industries.

The process of anaerobic digestion used for methane production can be enhanced by incorporating stimulating materials. The effects of these materials are dependent on various factors including the processed substrate, process conditions, and the type and amount of the stimulating material used. As part of the study, three different stimulating materials - iron powder, lime, and milled porous ceramic - were added to the 30-day anaerobic digestion of the brewer's spent grain to improve its performance. Different doses ranging from 0.2 to 2.3 gTS×L-1 were tested, and methane production kinetics were determined using the first-order model. The results showed that the methane yield ranged from 281.4±8.0 to 326.1±9.3 ml×gVS-1, while substrate biodegradation ranged from 56.0±1.6 to 68.1±0.7%. The addition of lime reduced methane yield at almost all doses by -6.7% to -3.3%, while the addition of iron powder increased methane yield from 0.8% to 9.8%. The addition of ceramic powder resulted in a methane yield change ranging from -2.6% to 4.6%. These findings suggest that the use of stimulating materials should be approached with caution, as even slight changes in the amount used can impact methane production.