Method Of Starting A Fuel Processor
In methods for starting a fuel processor, the equivalence ratio of reactants supplied to the fuel processor is controlled in a step-wise procedure to rapidly heat the fuel processor, and optionally sustain it within a desired temperature range until a hydrogen-containing gas stream is needed.
1 . A method of starting a fuel processor to produce a syngas stream comprising hydrogen and carbon-monoxide from a fuel reactant stream and an oxygen-containing reactant stream, said method comprising:
(a) supplying said fuel reactant stream and said oxygen-containing reactant stream to said fuel processor at a first equivalence ratio to ignite said combined fuel and oxygen-containing reactant streams;
(b) supplying said fuel reactant stream and said oxygen-containing reactant stream to said fuel processor at a second equivalence ratio to heat said fuel processor until a threshold temperature is reached; and
(c) supplying said fuel reactant stream and said oxygen-containing reactant stream to said fuel processor at a third equivalence ratio to produce said syngas stream.
2 . The method of claim 1 wherein said fuel processor is a non-catalytic fuel processor.
3 . The method of claim 1 wherein said second equivalence ratio is higher than said first and third equivalence ratios.
4 . The method of claim 1 wherein third equivalence ratio is substantially the same as said first equivalence ratio.
5 . The method of claim 1 wherein said first and third equivalence ratios are less than 1, and said second equivalence is about 1.
6 . The method of claim 2 further comprising in step (c) sustaining said third equivalence ratio at a substantially constant value until demand for said syngas stream ceases.
7 . The method of claim 2 wherein in between steps (b) and (c) said fuel processor is operated in a stand-by mode until there is demand for said syngas stream, by supplying said fuel reactant stream and said oxygen-containing reactant stream to said fuel processor at a standby equivalence ratio to maintain said fuel processor within a desired temperature range.
8 . The method of claim 7 wherein said second equivalence ratio is about 1 and said standby equivalence ratio is greater than 1.
9 . The method of claim 8 wherein said standby equivalence ratio is greater than 1.5.
10 . The method of claim 2 wherein in between steps (b) and (c) said fuel processor is operated in a stand-by mode until there is demand for said syngas stream, by alternately supplying said fuel reactant stream and said oxygen-containing reactant stream to said fuel processor at said second equivalence ratio and a standby equivalence ratio to maintain said fuel processor within a desired temperature range.
11 . The method of claim 10 wherein said second equivalence ratio is about 1 and said standby equivalence ratio is greater than 1.
12 . The method of claim 11 wherein said standby equivalence ratio is greater than 1.5.
13 . The method of claim 2 further comprising pre-heating at least one of said fuel reactant stream and said oxygen-containing reactant stream.
14 . The method of 13 wherein at least one of said fuel reactant stream and said oxygen-containing reactant stream is pre-heated by directing it through a heat exchanger coupled to said fuel processor such that heat from said fuel processor is transferred to said reactant stream.
15 . The method of claim 1 wherein in step (a), said supply of said fuel reactant stream to said fuel processor is started prior to starting said supply of said oxygen-containing reactant stream to said fuel processor.
16 . A method of operating a fuel processor to produce a syngas stream from a fuel reactant stream and an oxygen-containing reactant stream, said method comprising:
(a) supplying said fuel reactant stream and said oxygen-containing reactant stream at an equivalence ratio to said fuel processor to produce said syngas stream;
(b) lowering said equivalence ratio prior to shutting down said fuel processor in order to increase an amount of carbon produced in said syngas stream;
(c) collecting said carbon within said fuel processor;
(d) interrupting supply of said fuel reactant stream and said oxygen-containing reactant stream to said fuel processor to shut-down said fuel processor; and
(e) re-starting said fuel processor to produce said syngas stream,
wherein said carbon collected within said fuel processor is converted to increase syngas output during said re-starting of said fuel processor.
17 . The method of claim 16 wherein a particulate filter is employed within said fuel processor to collect said carbon.