Method for quick start-up of a fuel processing system using controlled staged oxidation
AssigneeGeneral Motors Corporation
InventorsGary M. Robb, William H. Pettit
Life of this patent
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Abstract
The present invention relates to controlled staged rich combustion throughout a fuel processing system in order to improve start up performance. Multiple stages of air injection are used to burn rich combustion products within each component to provide direct heating thereof. During the start up cycle, the fluid temperature entering each reactor is increased and each component is heated to its operating temperature in parallel. The controlled staged rich combustion eliminates the load imposed upon a combustor within the system during the start up cycle. Thus, each of the components within the fuel processing system may be optimized for an operational mode rather than a start up mode.
Claims30
A method of heating a fuel processing system from an ambient temperature to an operating temperature using controlled staged rich oxidation in a fuel processing system to improve startup performance, the method comprising the steps of:
- introducing a fuel stream and a first air stream into a primary reactor to form a first feed stream which is rich in fuel;
- heating said primary reactor to a first operating temperature range by oxidizing at least a portion said first feed stream in said primary reactor and forming a first effluent stream;
- introducing said first effluent stream and a second air stream into a secondary reactor to form a second feed stream which is rich in combustion products;
- and
- heating said secondary reactor to a second operating temperature range by oxidizing at least a portion of said second feed stream in said secondary reactor and forming a second effluent stream.
A method of heating a fuel processing system from an ambient temperature to an operating temperature using controlled staged rich oxidation in a fuel processing system to improve startup performance, the method comprising the steps of:
- introducing a fuel stream and a first air stream into a primary reactor to form a first feed stream which is rich in fuel;
- heating said primary reactor to a first operating temperature range by oxidizing at least a portion said first feed stream in said primary reactor and forming a first effluent stream;
- introducing said first effluent stream and a second air stream into a secondary reactor to form a second feed stream, said second feed stream being rich in combustion products and having an equivalence ratio such that the temperature of said secondary reactor will not exceed a maximum operating temperature thereof;
- heating said secondary reactor to a second operating temperature range by oxidizing at least a portion of said second feed stream in said secondary reactor and forming a second effluent stream which has a lower CO concentration than said first effluent stream;
- introducing said second effluent stream and a third air stream into a tertiary reactor to form a third feed stream, said third feed stream being rich in combustion products and having an equivalence ratio such that the temperature of said tertiary reactor will not exceed a maximum operating temperature thereof;
- and
- heating said tertiary reactor to a third operating temperature range by oxidizing at least a portion of said third feed stream in said tertiary reactor and forming a third effluent stream which has a lower CO concentration that said second effluent stream.
A method of heating a fuel processing system from an ambient temperature to an operating temperature using controlled staged rich oxidation in a fuel processing system to improve startup performance, the method comprising the steps of:
- introducing a fuel stream and a first air stream into a primary reactor to form a first feed stream which is rich in fuel;
- heating said primary reactor to a first operating temperature range by oxidizing at least a portion said first feed stream in said primary reactor and forming a first effluent stream;
- introducing said first effluent stream and a second air stream into a high temperature water gas shift reactor to form a second feed stream, said second feed stream being rich in combustion products and having an equivalence ratio such that the temperature of said high temperature water gas shift reactor will not exceed a maximum operating temperature thereof;
- heating said high temperature water gas shift reactor to a second operating temperature range by oxidizing at least a portion of said second feed stream in said high temperature water gas shift reactor and forming a second effluent stream;
- introducing said second effluent stream and a third air stream into a low temperature water gas shift reactor to form a third feed stream, said third feed stream being rich in combustion products and having an equivalence ratio such that the temperature of said low temperature water gas shift reactor will not exceed a maximum operating temperature thereof;
- heating said low temperature water gas shift reactor to a third operating temperature range by oxidizing at least a portion of said third feed stream in said low temperature water gas shift and forming a third effluent stream;
- introducing said third effluent stream and a fourth air stream into a preferential oxidation reactor to form a fourth feed stream, said fourth feed stream being rich in combustion products and having an equivalence ratio such that the temperature of said preferential oxidation reactor will not exceed a maximum operating temperature thereof;
- heating said preferential oxidation reactor to a fourth operating temperature range by oxidizing at least a portion of said fourth feed stream in said preferential oxidation reactor and forming a fourth effluent stream;
- introducing said fourth effluent stream and a fifth air stream into a combustor to form a fifth feed stream;
- and
- oxidizing said fifth feed stream in said combustor to form an exhaust stream which is discharged therefrom.
Dependencies are inferred from the claim text.