CONTINUOUS HYDROGEN RICH SYNGAS PRODUCTION VIA SUPERCRITICAL WATER GASIFICATION

Abstract

The supercritical water gasification (ScWG) technology is a promising alternative to produce hydrogen rich syngas from renewable sources such as ethanol or residual glycerol from the biodiesel manufacture. The ScWG process can achieve high selectivity towards hydrogen and elevated conversion efficiencies in short reaction times. In this work, the ScWG of mixtures of glycerol and ethanol were investigated in the absence of catalysts. At constant pressure of 25 MPa, the effects of temperature (500 – 700 °C), feed flow rate (10 – 20 mL min-1), organic carbon concentration (15 – 25 g L-1), and ethanol to glycerol ratio were evaluated. At optimized conditions, that is, temperature of 700 °C, feed flow rate of 20 mL min-1, organic carbon concentration of 25 g L-1 and ethanol to glycerol ratio of 50:50, a mean total gaseous flow rate and hydrogen molar fraction of 1842.5 N mL min-1 and 60.56% were respectively achieved.