ENERGY RECOVERY

摘要

A PSA based process for the production of technical hydrogen wherein the feed to the PSA contains nitrogen and carbon monoxide with a hydrogen/(carbon monoxide + nitrogen) volume ratio in the range 1.2 to 4 and a nitrogen/carbon monoxide volume ratio of at least 10. The adsorption step in the PSA stage is stopped when the integrated nitrogen content of the unadsorbed product is 1 to 10% by volume. The raw gas fed to the PSA is preferably made by a primary reforming a hydrocarbon feedstock with steam followed by secondary reforming followed by shift and water removal: the heat required for primary reforming is preferably supplied by the secondary reformer outlet gas. The PSA waste gas is preferably combusted in a gas turbine driving the secondary reformer air compressor.