The use of additives in the enzymatic saccharification of lignocellulosic biomass can have positive effects, decreasing the unproductive adsorption of cellulases on lignin and reducing the loss of enzyme activity. Soybean protein stands out as a potential lignin-blocking additive, but the economic impact of its use has not previously been investigated. Here, a systematic evaluation was performed of the process conditions, together with a techno-economic analysis, for the use of soybean protein in the saccharification of hydrothermally pretreated sugarcane bagasse in the context of an integrated 1G-2G ethanol biorefinery. Statistical experimental design methodology was firstly applied as a tool to select the process variable solids loading at 15% (w/w) and soybean protein concentration at 12% (w/w), followed by determination of enzyme dosage at 10 FPU/g and hydrolysis time of 24 h. The saccharification of sugarcane bagasse under these conditions enabled an increase of 26% in the amount of glucose released, compared to the control without additive. The retro-techno-economic analysis (RTEA) technique showed that to make the biorefinery economically feasible, some performance targets should be reached experimentally such as increasing biomass conversion to ideally 80% and reducing enzyme loading to 5.6 FPU/g in the presence of low-cost soybean protein.

In a carbon-neutral economy, biorefineries may replace oil refineries, providing materials and molecules. One of these products are biosurfactants (BSs), which can be produced from sugarcane bagasse. Two different processes for BS production were proposed and evaluated from a technoeconomic environmental perspective. Global sensitivity and uncertainty analyses (GSA and UA) assessed the most influential variables and the uncertainties regarding the minimum BS selling price (MBSSP), together with several environmental metrics. Both processes presented positive economic performance. The analysis showed that the second scenario (using liquid hot water pretreatment without detoxification and BS recovery by two steps of ultrafiltration) presented superior economic and environmental performance. The second scenario had a 59.7% probability of having a MBSSP below 20 $/kg, against 47.1% for the first one. GSA showed that effort should be focused on decreasing uncertainty regarding the bioreactor performance and scaleup (for both scenarios) and the ultrafiltration performance (for the second scenario).

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