Essential oil distillation residue as environmentally friendly feedstock in gasification: effect of dry air flow rate and temperature on gasification performance

Abstract

Despite the growing use of distillation to extract essential oils from aromatic plants, their residues pose a challenge due to their high cellulose-lignin content and resistance to biodegradation, requiring thermochemical treatment for removal. This paper presents the effect of flow rate of agent and operation temperature on the gasification of Oregano (Origanum onites L.) and Lavender (Lavandula angustifolia) distillation residue in an updraft fixed bed reactor. The syngas composition, lower heating value of syngas, carbon conversion efficiency, cold gas efficiency, and amount of product are assessed during gasification process. In the experimental studies, a laboratory-scale upstream fixed-bed gasification reactor made of stainless steel heated with a ceramic heater resistant was used. The studies were carried out at temperatures of 700, 800, and 900 degrees C and a dry air flow rate of 0.05-0.4 L/min to find optimum conditions for gasification. Results showed that increasing the temperature and reducing the dry air flow rate led to higher syngas production and heating value. The maximum volume of H2 in the syngas was measured as 40%. The HHV varied between 5 and 13 MJ/Nm3. The optimum flow rate and temperature for gasification in the updraft fixed bed reactor were found to be 0.05-0.1 L/min and 900 degrees C, respectively.