In some aspects, a method for incremental hydrogen production includes separating in a first Pressure Swing Absorption (PSA) system an existing reformer synthesis gas product stream into a first hydrogen stream and a first waste stream. The first waste stream is compressed to at least 40 bar to produce a compressed waste stream. Water is removed from the compressed waste stream to produce a dried waste stream. Carbon dioxide is removed from the dried waste stream to produce a remaining waste stream, and the removed carbon dioxide is at least 85% of carbon dioxide in the existing reformer synthesis gas product stream. A second PSA system separates the remaining waste stream into a second hydrogen stream and a second waste stream, and the second hydrogen stream comprises at least 11% of hydrogen from the existing reformer synthesis gas product stream.