Use of nitrogen from an air separation plant in carbon dioxide removal from a feed gas to a further process
AssigneeAir Products and Chemicals, Inc.
InventorsJames M. Occhialini, Rodney J. Allam, Mohammed A. Kalbassi
Life of this patent
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Abstract
A cryogenic air separation unit (ASU) provides flows of oxygen and nitrogen. The oxygen is used in a process such as COREX iron making or the partial oxidation of hydrocarbons, or in an oxycoal fuelled blast furnace, producing an off-gas containing useful components (H.sub.2 and CO) and carbon dioxide. The carbon dioxide is removed by pressure swing adsorption using nitrogen from the ASU as a regeneration gas and the purified off-gas becomes a feed gas to a further process such as production of iron by direct reduction of iron ore or the production of a NH.sub.3 making ammonia or is recycled into the first process as a feed gas.
Claims17
A method for the separation of air into oxygen and nitrogen and for the use of nitrogen so produced, which method comprises operating a cryogenic air separation unit to produce oxygen and nitrogen, operating a process which produces an off-gas containing carbon dioxide mixed with at least one other gas, and removing carbon dioxide from said off-gas by alternating adsorption of the carbon dioxide onto an adsorbent and the regeneration of the adsorbent under a flow of said nitrogen from the air separation unit.
Apparatus for the separation of air into oxygen and nitrogen and for the use of nitrogen so produced, which apparatus comprises:
- a cryogenic air separation unit having an inlet for air to be separated and outlets for oxygen and nitrogen as separated components of said air,
- apparatus for conducting a process having an inlet for feed materials for said process and an outlet for carbon dioxide containing off-gas produced in said process,
- a carbon dioxide removal unit containing a regenerable adsorbent and having an inlet for said off-gas as a feed gas to the carbon dioxide removal unit, an inlet for nitrogen as a purge gas for regeneration of the adsorbent in said carbon dioxide removal unit and an
- outlet for said off-gas containing a decreased concentration of carbon dioxide, and
- means for supplying nitrogen from said nitrogen outlet of the air separation unit to the inlet for nitrogen of the carbon dioxide removal unit.
Dependencies are inferred from the claim text.