Study of process factor effects and interactions in synthesis gas production via a simulated model for glycerol steam reforming

Abstract

With the continual global focus in biodiesel production, a glut of glycerol (it's by-product) is expected in the world market. One viable and proven possibility in utilising the less useful and desired glycerol as a source for the production of hydrogen via the steam reforming and water gas shift process. This study is essentially and in-depth investigation of the interaction of the key process factors and their effect on the selectivity of Hydrogen from the process. The basis of the investigation was a simulated model of the steam reforming process using ASPEN plus V8.8. Results were obtained according to the optimisation plan developed using central composite design (CCD). The variables (and range) were temperature (700 0 c - 1100 0 c), Pressure (0.1 atm - 1.9 atm) and steam to glycerol ratio (1mol/mol - 12mol/mol). The results of optimisation showed that maximum yield of H 2 and minimal methanation can be obtained at a temperature of 900 0 c, an STGR of 15.75mol/mol and at atmospheric pressure. The optimum result was predicted by the simulation as H 2 = 66.72%, CO = 11.76%, CO 2 = 21.52% and CH 4 = 0%. Sensitivity analysis was carried out to show that Hydrogen production is favoured at higher temperatures and methanation at lower temperatures respectively. A critical investigation of the factor effects and interactions for each product in the synthesis gas (dry basis) was also carried out using response surface methodology.