Circular economy in apple processing industry: Biodiesel production from waste apple seeds

Apple pomace is a solid waste derived from the apple processing industry. To foster sustainability, the apple processing industry must implement the circular economy model of biorefinery and treat apple pomace as a valuable source of apple seed oil. The first time, this study dealt with the design, economic, and potential environmental impact assessment of biodiesel production using apple pomace as a source of apple seed oil. An Aspen Plus? and WAR? software were used to evaluate the designed biodiesel production. Supercritical CO2 extraction and methanolysis of apple seed oil, methanol recovery, and biodiesel separation were the main production steps. The production facility was assumed to process 24 tons of apple seeds daily. The total capital and production costs were 1.26 US$ million and 2.82 US$ million, respectively. If revenues from selling apple seed meal as cattle feed were included, a biodiesel price could be 0.39 US$/kg. The process was environmentally friendly when apple seed meal was not treated as waste.