Scale-Up of Liquid Hydrocarbon Production using Gasified Biomass

This study showed that liquid hydrocarbons could be successfully created while also effectively controlling temperature using a proportional-integral-derivative (PID) control system in a scaled-up reactor system. A stainless steel tube reactor that measured 2 feet long with a 1.689 inch inside diameter was used to conduct the experiments. Tests were run at a gas hourly space velocity (GHSV) of 500 h-1 (1.4 SLPM) with a catalyst bed volume of 175 mL (93.6g) and a bed height of 4.8 inches. Syngas was subjected to 330o C at 1000 psi, 300o C at 800 psi, 300o C at 600 psi, and 300o C at 500 psi; while the producer gas was tested at 300o C at 1000 psi. An iron-based bi-functional catalyst that converted the syngas to liquid hydrocarbons in one step was used with (Airgas) synthesis gas and producer gas composed of approximately 18% H2, 23% CO, 11% CO2, 2% CH4, and 46% N2. The similar mole percentages from the store bought syngas (Airgas syngas) was used to mimic the producer gas from our particular downdraft gasifier, but the producer gas included 1% O2. Results indicated that the hydrogen conversion ranged from approximately 71% to 85% for all the tests while the conversion of CO ranged from approximately 87% to 96%. The heat generated was able to be properly controlled, and liquid hydrocarbons were successfully created from the producer gas and the store bought syngas.