The aim of this study was to investigate hemp processing scenarios in techno-economic aspect. The process model built in Aspen Plus V7.3 was based on experimental data. The feedstock was chopped hemp stem in all scenarios. In scenarios A and B it was subjected to anaerobic digestion (AD) directly or after fine-grinding, respectively. In scenario C steam-pretreatment was performed on the feedstock, and then the whole slurry was sent to AD. In scenario D the whole slurry obtained after steam-pretreatment was separated into liquid and solid fractions. The latter was used in simultaneous saccharification and fermentation to produce ethanol, which was separated by distillation. The stillage from the distillation and liquid fraction of the whole slurry were subjected to AD. In all scenarios mentioned so far effluent of AD was filtered, and the liquid fraction was assumed to be used as fertiliser, while the solid fraction was burnt to generate heat and power. Scenario E was the same as scenario D, except that AD was not included, therefore organic material of stillage and of liquid fraction after steam-pretreatment was used in heat and power production. A comparison of the five scenarios based on energy efficiency and production cost will be presented.
See more of: General Submissions