CALCIUM LOOPING PROCESS FOR HIGH PURITY HYDROGEN PRODUCTION INTEGRATED WITH CAPTURE OF CARBON DIOXIDE, SULFUR AND HALIDES

摘要

A process for producing hydrogen comprising the steps of: (i) gasifying a fuel into a raw synthesis gas comprising CO, hydrogen, steam, sulfur and halide contaminants in the form of H2S, COS, and HX, wherein X is a halide; (ii) passing the raw synthesis gas through a water gas shift reactor (WGSR) into which CaO and steam are injected, the CaO reacting with the shifted gas to remove CO2, sulfur and halides in a solid-phase calcium-containing product comprising CaCO3, CaS and CaX2; (iii) separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; and (iv) regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of CO2, in the presence of synthesis gas, in the presence of H2 and O2, under partial vacuum, and combinations thereof.

主权项

1. A process for producing hydrogen, comprising the steps of:
reforming a gaseous hydrocarbon fuel in the presence of CaO and steam to remove C02, sulfur and halide contaminants in the form of H2S, COS and HX, wherein X is a halide, in a solid-phase calcium-containing product comprising CaCO3, CaS and CaX2, thereby producing a mixture of CO and hydrogen: separating the solid-phase calcium-containing product from an enriched gaseous hydrogen product; regenerating the CaO by calcining the solid-phase calcium-containing product at a condition selected from the group consisting of: in the presence of steam, in the presence of C02, in the presence of synthesis gas, in the presence of H2 and O2, under partial vacuum, and combinations thereof; reactivating the calcined sorbent by hydrating it in the presence of steam or water or a mixture of both; and injecting the hydrated sorbent into the reforming unit.