Ammonia and urea production in reverse flow reactors

A method for performing reforming, comprising:

• reacting a fuel mixture comprising a fuel stream, an oxygen-containing stream comprising 10 vol % or less N2 relative to a volume of the oxygen-containing stream, and a recycle stream under combustion conditions comprising a combustion pressure of 0.7 MPa-g or more in a combustion zone within a reactor to form a flue gas and to heat one or more surfaces in a reaction zone to a regenerated surface temperature of 600° C. or more, the reaction zone comprising a catalyst composition, the fuel mixture comprising 0.1 vol % or more O2 and 20 vol % or more CO2 relative to a volume of the fuel mixture;
• separating, from the flue gas, at least a portion of the recycle stream and a CO2-containing stream comprising a second pressure of 0.5 MPa-g or more;
• exposing a hydrocarbon-containing stream to the catalyst composition in the reaction zone at the regenerated surface temperature under reforming conditions to form a reforming product stream comprising H2 and CO, a direction of flow for the hydrocarbon-containing stream within the reaction zone being reversed relative to a direction of flow for the fuel mixture;
• forming an H2-containing stream comprising 50 vol % or more H2 from at least a portion of the reforming product stream;
• methanating at least a portion of the H2-containing stream to form a methanated H2-containing stream;
• and,
• exposing the methanated H2-containing stream to ammonia synthesis conditions in the presence of N2 to form an ammonia-containing product,
• wherein optionally at least one of the recycle stream and the fuel mixture comprises 15 vol % or less of N2.

A method for performing reforming, comprising:

• reacting a fuel mixture comprising a fuel stream and an oxygen-containing stream under combustion conditions in a combustion zone within a reactor to form a flue gas and to heat one or more surfaces in a reaction zone to a regenerated surface temperature of 600° C. or more, the reaction zone comprising a catalyst composition, the oxygen-containing stream further comprising N2, the fuel mixture comprising 0.1 vol % or more O2 relative to a volume of the fuel mixture;
• separating, from the flue gas, an N2-containing stream comprising 95 vol % or more N2;
• exposing a hydrocarbon-containing stream to the catalyst composition in the reaction zone at the regenerated surface temperature under reforming conditions to form a reforming product stream comprising H2 and CO, a direction of flow for the hydrocarbon-containing stream within the reaction zone being reversed relative to a direction of flow for the fuel mixture;
• and
• forming an H2-containing stream comprising 50 vol % or more H2 from at least a portion of the reforming product stream;
• methanating at least a portion of the H2-containing stream to form a methanated stream;
• and exposing the methanated stream and at least a portion of the N2-containing stream to ammonia synthesis conditions to form an ammonia-containing product.

An ammonia synthesis system comprising:

• a reactor comprising a reactor inlet at a first end of the reactor, a regenerator inlet at a second end of the reactor, and a reaction zone comprising reforming catalyst;
• a recycle loop providing intermittent fluid communication between the reactor inlet and the regenerator inlet, the recycle loop comprising a recycle compressor, a fuel source inlet, an oxygen-containing gas inlet, and a CO2-containing gas outlet;
• an air separation unit in fluid communication with the oxygen-containing gas inlet;
• a pressure swing adsorption separator, the regenerator inlet being in intermittent fluid communication with the pressure swing adsorption separator;
• a methanation stage in fluid communication with the regenerator inlet via the pressure swing adsorption separator;
• and,
• an ammonia synthesis stage in fluid communication with the methanation stage.