초록 ▼

A method and apparatus for separating gas mixtures containing synthesis gas (syngas) into separate streams of wet hydrogen containing significantly reduced amounts of CO2and CO, with the CO2being "sequestration ready" and containing less than 1% fixed gases. In the preferred embodiment, a mixture of

A method and apparatus for separating gas mixtures containing synthesis gas (syngas) into separate streams of wet hydrogen containing significantly reduced amounts of CO2and CO, with the CO2being "sequestration ready" and containing less than 1% fixed gases. In the preferred embodiment, a mixture of limestone and iron oxide circulates between two fluidized beds whereby one bed is fluidized with a gas containing syngas, while the other bed is fluidized with a gas containing steam and oxygen. As the fluidizing gas containing syngas passes through the bed, the CO2reacts with CaO to form CaCO3. Virtually all of the CO is removed by a water gas shift reaction, forming hydrogen and CO2,with the remainder being removed by reaction with the iron oxide, reducing Fe2O3to FeO. Some hydrogen is also removed by reaction with the iron oxide, reducing Fe2O3to FeO, while the remainder of the hydrogen passes through the fluid beds, leaving in a purified state, i.e., PEM fuel cell quality.

대표청구항 ▼

1. A process for separating syngas into fuel cell quality hydrogen and sequestration ready carbon dioxide, comprising the steps of circulating a mixture of solids comprising calcium compounds present as CaO, Ca(OH)2and CaCO3and mixtures thereof, and iron compounds present as FeO, Fe2O3,Fe3O4and m

1. A process for separating syngas into fuel cell quality hydrogen and sequestration ready carbon dioxide, comprising the steps of circulating a mixture of solids comprising calcium compounds present as CaO, Ca(OH)2and CaCO3and mixtures thereof, and iron compounds present as FeO, Fe2O3,Fe3O4and mixtures thereof, between first and second fluidized bed reactors; charging said first fluidized bed reactor with a first gas mixture (syngas) containing high temperature steam, H2,CO2and CO; charging said second fluidized bed reactor with a second gas mixture containing high temperature steam and oxygen; reacting CO2present in said first gas mixture with CaO present in said first fluidized bed reactor to form CaCO3; reacting a portion of CO present in said first gas mixture with steam in a water gas shift reaction to form hydrogen and CO2and reacting the remaining portion of CO present in said first gas mixture with iron oxide to form FeO and CO2; circulating CaCO3and FeO formed in said first fluidized bed reactor to said second fluidized bed reactor; oxidizing FeO present in said second fluidized bed reactor to form Fe2O3; removing substantially pure hydrogen from said first fluid bed reactor; and removing CO2and SO2from said second fluid bed reactor. 2. The process according to claim 1, wherein the solids in said reactor are fluidized using high temperature steam and syngas and the solids in said second reactor are fluidized using high temperature steam and oxygen. 3. The process of claim 1, wherein the temperature in said first fluidized bed reactor is between 400° C. to 450° C. and the pressure is between 100 psig and 500 psig. 4. The process of claim 1, wherein the temperature in said second fluidized bed reactor is between 800° C. to 1200° C. and the pressure is between 100 psig and 500 psig. 5. The process of claim 1, wherein the rate of solids circulation between said first and second fluidized beds is such that the ratio of FeO entering the second bed to oxygen in said second gas mixture is greater than 4 to 1 but less than 5 to 1. 6. The process of claim 1, wherein the ratio of atoms of iron present as FeO, Fe3O4and Fe2O3in said circulating mixture of solids is between 1.5 and 2. 7. The process of claim 1, wherein said syngas entering said first fluidized bed reactor includes H2S which reacts with FeO and CaO to form FeS and CaS. 8. The process of claim 1, wherein said first fluidized bed reactor is operated in a bubbling or entrained flow mode. 9. The process of claim 1, wherein said second fluidized bed reactor is operated in a counterflow mode. 10. The process of claim 1, wherein the solids and gases exiting said first fluidized bed reactor are separated into a gaseous stream consisting of essentially pure hydrogen and steam and a solid stream consisting principally of FeO, Fe2O3,Fe3O4,FeS, CaO, Ca(OH)2,CaCO3and CaS.