Process and relating apparatus to make pure hydrogen from a syngas originated from wastes gasification

A process for making hydrogen without any emission of nitrogen and sulphur, comprising the following steps:

• gasification in a gasification reactor of a carbon-matrix waste to produce raw syngas, wherein the carbon matrix waste is selected from the group consisting of municipal waste and refuse derived fuel;
• pretreatment (210) of the raw syngas to remove particulates, metals, chlorine, and NH3 compounds, to produce a pretreated syngas;
• conversion (220) where HCN, CO and COS present in the pretreated syngas are converted into N2, CO2 and H2S in presence of H2S, wherein the conversion comprises a high temperature sour shift reaction (223) where the HCN, COS and CO are converted through the following reactions:
• COS+H2O ⇄CO2+H2S
• CO+H2O ↔CO2+H2
• 2 HCN+2H2O→N2+2 CO+3H2;
• removal (230) where H2S is removed from the pretreated syngas and then transformed into elementary S;
• and
• purification (240) where CO2 is removed from the pretreated syngas via a cryogenic unit or an amine unit, and pure hydrogen is produced by a pressure swing absorption unit,
• wherein the method further comprises,
• wherein the H2S level in the raw syngas by adding waste containing S into the gasification reactor, wherein the increasing is to maintain a concentration high enough to carry out the high temperature sour shift reaction (223).