Design and Testing of a Commercial Prototype Press to Extract the Juice from Sweet Sorghum Biomass

Abstract

HighlightsA commercial-scale prototype press to extract the juice from sweet sorghum biomass was designed, built, and tested.Extraction rates of up to 45% were obtained with this prototype.Abstract. With the rising concerns related to climate change issues, different alternatives have been explored to reduce the use of fossil fuels. Laws forcing the use of ethanol at gas pumps have been enforced across North America. While ethanol is a good alternative, it is mainly made from corn, which is a very demanding crop in terms of water, fertilizers, and climate conditions. The sweet sorghum has been proved to be a good alternative crop, but current pressing methods require transportation of the biomass to a plant, thus resulting in high transportation costs and emissions as well as depriving the soil from an important source of fertilization, which is the pressing residue. The objective of this research was to develop and test a commercial scale prototype press able to extract juice from the sweet sorghum directly in the field. A sequential two-chamber piston press able to apply up to 1.6 MPa of pressure on the biomass was developed and tested. The prototype press was used in extracting juice from sweet sorghum and the influence of operational parameters (pressure and extraction time) on the extraction rate and juice yield was evaluated. Sweet sorghum plants were first harvested and chopped with a forage harvester, then weighed and pressed. The pressing juice was collected and the residue (bagasse) was returned to the field as fertilizer. Obtained results from pressing tests carried out in 2014, 2015, and 2018 showed a juice extraction rate of up to 45% of the initial weight of the biomass. Keywords: Bioethanol, Biomass, Ethanol, Juice, Pressing, Sweet sorghum.