US 7,332,146 B1 · Method for zero emission liquid hydrogen production from methane and landfill gas

Abstract

Processes, methods, systems and devices for zero emission liquid hydrogen production directly from a variety of methane sources, such as natural gas and landfill gas, are disclosed. Five embodiments of plant designs for liquid hydrogen production are presented. The embodiments combine hydrogen production and liquefaction into a single process to produce liquid hydrogen directly via methane containing gases; thus, eliminating the conventional technology of pressure swing adsorption process for gas mixture separation. The innovative process can be applied to produce high purity liquid hydrogen with no carbon dioxide emission to the atmosphere; and can also co-produce highly pure solid carbon and liquid carbon dioxide as by-products for industrial application. The invention has provided advantages over conventional approaches that result in up to approximately 85% of first low efficiencies and approximately 56% of second law efficiency, up to approximately 100% of hydrogen and methane recovery, and a very high purity of liquid hydrogen (99.9999%).

Claims12

Dependent claims

A cryogenic method for hydrogen cryogenic liquefaction and hydrogen separation for liquid hydrogen (LH2) production comprising the steps of:

(a) producing a hydrogen rich gas mixture containing H2, CO, CO2, CH4, H2O and trace amounts of hydrocarbons;
(b) cryogenically separating the gas mixture of step (a) resulting in H2O, and liquid carbon dioxide (LCO2);
(c) separating low temperature gaseous H2 and gas mixture of CO and CH4;
(d) recycling the CO and CH4 of the gas mixture to further produce hydrogen rich gas;
(e) mixing the hydrogen rich gas from step (d) with the hydrogen rich gas mixture in step (a) to form a closed loop for CO and CH4 gas mixture;
(f) further cooling the low-temperature gaseous hydrogen until it is liquefied;
and
(g) producing LH2 without CO2 emission.

5 more elements

Dependencies are inferred from the claim text.

Method for zero emission liquid hydrogen production from methane and landfill gas

Life of this patent

Method for zero emission liquid hydrogen production from methane and landfill gas

Life of this patent

Abstract

Claims12