PROCESSES FOR THE RECOVERY OF HIGH PURITY HYDROGEN AND HIGH PURITY CARBON DIOXIDE

摘要

The present invention relates to various processes for recovering high purity gaseous hydrogen and high purity gaseous carbon dioxide from the gas stream produced using steam hydrocarbon reforming, especially steam methane reforming, utilizing a H2 pressure swing adsorption unit followed by either a CO2 vacuum swing adsorption unit or a CO2 vacuum swing adsorption unit in combination with an additional CO2 pressure swing adsorption unit. By using an uncoupled H2 PSA and CO2 VSA unit it is possible to produce high purity H2 and high purity CO2. The present invention further relates to a process for optimizing the recovery of CO2 from waste gas streams produced during the hydrogen purification step of a steam hydrocarbon reforming/H2 pressure swing adsorption unit utilizing either a CO2 vacuum swing adsorption unit or a CO2 vacuum swing adsorption unit in combination with a CO2 pressure swing adsorption unit. The present invention even further relates to the apparatus necessary to carry out the various processes of the present invention.