Produce a CO-rich synthesis gas. Products: Pure CO and H2, or mixtures of CO and H2 (synthesis gas), are used to manufacture many chemicals, e.g., acetic acid, oxo-alcohols and isocyanates.
Advanced steam reforming in a firedtubular reformer is the predominant process route for medium-sized synthesis gas plants. The Topsøe sidefired reformer and reforming catalysts enable operating at low steam-to-carbon ratios, high reformer outlet temperature and high heat flux.
The hydrocarbon feedstock can be natural gas, LPG or naphtha. For heavy feedstocks, an adiabatic prereformer is needed upstream of the tubular reformer. Carbon dioxide (CO2) import and/or CO2 recycle is applied to produce CO-rich synthesis gas. The unit typically consists of a feed desulfurization, pre-reforming, tubular reforming, CO2 recovery and recycle, and final purification. Purification of the synthesis gas by membrane, cold box and PSA is dependent on the required end-product specifications.
Operating conditions: Typically, CO-rich synthesis gas is obtained at feed ratios of H2O/CH4 = 1.5 to 2.0 with CO2 recycle and/or CO2 import. This results in H2/CO ratios down to 1.8 at reformer exit temperatures of 950°C (1,740° F). Even lower H2/CO ratios can be obtained by CO2 reforming using the SPARG process or by applying a high-activity, noble-metal reforming catalyst.
Economics: Production CO-rich synthesis gases at advanced steam reforming conditions offers significant savings in operating and investment costs.
Licensor: Haldor Topsøe A/S