摘要:
A fuel cell system includes a fuel cell for reacting a hydrogen rich gas; a fuel processor system for converting a hydrocarbon fuel-steam mixture into said hydrogen rich gas; and a system for preparing the hydrocarbon fuel-steam mixture which includes (a) structure for superheating a hydrocarbon fuel so as to provide a superheated fuel, and (b) structure for mixing water with the superheated fuel so as to provide the hydrocarbon fuel-steam mixture.
摘要:
A mass and heat recovery system for a fuel cell power plant includes at least one fuel cell for producing electrical energy, hydrocarbon fuel processing components for producing a hydrogen rich reducing fluid for the fuel cell, and a direct mass and heat transfer device for recovering mass and heat such as water vapor leaving the plant. The fuel processing components include an auxiliary burner that provides heat to generate steam and a reformer that receives the steam mixed with a hydrocarbon fuel along with a small amount of air and converts the mixture to a hydrogen rich stream appropriate for supplying hydrogen to the anode electrode. The direct mass and heat transfer device passes a process oxidant stream upstream of the plant in mass transfer relationship with a plant exhaust stream that includes both a cathode exhaust stream and an anode exhaust stream wherein the anode exhaust stream has first been burned in the auxiliary burner so that mass and heat such as water vapor in the plant exhaust stream transfer directly through a mass transfer medium of the device to the process oxidant stream entering the plant. The device includes a separator housing for supporting the transfer medium and for preventing bulk mixing of the streams. An exemplary transfer medium such as a liquid water portion of a water saturated polyflourosulfonic ionomer selectively sorbs a fluid substance consisting of polar molecules such as water molecules from a fluid stream containing polar and non-polar molecules.
摘要:
A fuel cell power plant system includes the ability to operate an enthalpy recovery device even under cold conditions. A bypass arrangement allows for selectively bypassing one or more portions of the enthalpy recovery device under selected conditions. In one example, the enthalpy recovery device is completely bypassed under selected temperature conditions to allow the device to freeze and then later to be used under more favorable temperature conditions. In another example, the enthalpy recovery device is selectively bypassed during a system startup operation. One example includes a heater associated with the enthalpy recovery device. Another example includes preheating oxidant supplied to one portion of the enthalpy recovery device.
摘要:
A control method and arrangement (48, 50, 150, I, T, P, FFL) are provided in a fuel cell power plant (10) for regulating (48, FC) fuel flow to a steam-based fuel processing system (FPS) (14) associated with a low-temperature fuel cell stack assembly (12). A portion of the fuel provided by the FPS (14) is used to provide steam for the FPS. The fuel flow to the FPS is regulated as a function of the power demand (I) on the fuel cell (12) and at least the enthalpy of the steam (P, T), such that the steam enthalpy is regulated to meet increases and decreases in power demand without exceeding steam pressure limits. In addition to reliance on-steam pressure (P) as a fundamental measure of steam enthalpy, the control may additionally use reaction temperature (T) at, or in, a reformer, such as a catalytic steam reformer (132), to regulate fuel flow and thus, steam enthalpy.
摘要:
A method for operating a fuel cell power plant to provide end-use electricity, end-use heat and end-use reformate includes the steps of providing a fuel cell power plant that consumes reformate to provide electricity and heat, said fuel cell power plant having a nominal reformate flow rate and including a fuel processor system for generating reformate from a hydrocarbon fuel; operating the fuel processor system so as to provide a reformate flow at a rate greater than the nominal reformate flow rate; operating the fuel cell power plant using a first portion of the reformate flow to generate the electricity and the heat, the first portion being less than or equal to the nominal reformate flow rate; and providing a second portion of the reformate flow as the end-use reformate.
摘要:
A thermal priority fuel cell power plant includes a cell stack assembly for generating an electrical power output. The cell stack assembly includes an anode, a cathode, and a waste heat recovery loop. The waste heat recovery loop is configured to remove waste heat generated from the electrochemical reaction and is thermally coupled to the cell stack assembly for managing the waste heat of the cell stack assembly and for supplying thermal power to a thermal load demand. The waste heat recovery loop includes a heat exchanger in heat exchange relationship with the coolant outlet conduit and the thermal load demand. A controller is operatively associated with the cell stack assembly and the waste heat recovery loop. The controller controls the operation of the cell stack assembly by adjusting a fuel cell power plant parameter responsive to the thermal load demand.
摘要:
A thermal priority fuel cell power plant includes a cell stack assembly for generating an electrical power output. The cell stack assembly includes an anode, a cathode, and a waste heat recovery loop. The anode is configured to receive a fuel, the cathode is configured to receive an oxidizer, and the cell stack assembly is configured to generate the electrical power output by electrochemically reacting the anode fuel and the cathode oxidizer in the presence of a catalyst. The waste heat recovery loop includes a coolant inlet conduit and a coolant outlet conduit, and is configured to remove waste heat generated from the electrochemical reaction. A waste heat recovery loop is thermally coupled to the cell stack assembly for managing the waste heat of the cell stack assembly and for supplying thermal power to a thermal load demand. The waste heat recovery loop includes a heat exchanger in heat exchange relationship with the coolant outlet conduit and the thermal load demand. A controller is operatively associated with the cell stack assembly and the waste heat recovery loop. The controller controls the operation of the cell stack assembly by adjusting a fuel cell power plant parameter responsive to the thermal load demand. In one aspect, the fuel cell power plant parameter is reactant utilization. In another aspect, the fuel cell power plant parameter is a temperature for a thermal management system accumulator.
摘要:
A vane (31) at the juncture of orthogonal conduits (25–28) allows flow of air to and from the air inlet/outlet manifold (12) of a fuel cell stack (11) when it is disposed in a first position, and totally blocks the conduits (25, 26) so as to isolate the air flow fields of the fuel cells (17, 18) when in a position normal to the first position. A vane (41) can comprise the divider of the air inlet/outlet manifold when in a vertical position, and totally block off the manifold when in a horizontal position. A vane (59) can align with the divider (24) of an air inlet/out manifold when in a vertical position, and block the passage between the manifold and conduits (44, 46) when in a horizontal position. Similar vanes may be used for single-valve selection of flow or containment of fuel reactant gas.
摘要:
A fuel cell system that includes fuel processing components, such as a reformer and shift converter, for converting an organic fuel to hydrogen, is shut-down by disconnecting the fuel cell from its load and purging the fuel processing components of residual hydrogen with a flow of air. The purge air may be forced through the components in series or in parallel, using a blower; or, the purge air may be allowed to enter the components through a low inlet, whereupon the air rises through the components by natural circulation and exits through a high outlet, along with the residual hydrogen.
摘要:
A method and system are provided for controlling a fuel cell power plant (10). A demand signal (Mld) representing the anticipated current/power required by the electrical load(s) is provided. A current signal (Iap) representative of the actual current drawn by the load(s) (20) is provided. The greater of the demand signal (Mld) and the current signal (Iap) is selected (46) and utilized to provide a control signal (Mx, Mx′, Mx″) for regulating one or more of the reactants and coolant (24). One or more status signals (Xp, Xp′, Xp″, Vap) indicative of the status of a regulated one of more of the reactant/coolant and/or a respective operating process effected, is provided. Each status signal is transformed to a respective load capability signal (61, 61′, 61″). The lesser of the demand signal (Mld) and each of the load capability signals (61, 61′, 61 ″) is selected (62) to provide an output signal (Mi) for commensurately controlling a system load (20, 32).