Coolant conditioning system and method for a fuel processing subsystem
View Patent ↗A coolant conditioning system is provided for supplying a coolant flow to a fuel processing subsystem. The coolant conditioning system includes a coolant preheater to transfer heat from a reformate flow to the coolant flow, a heater to selectively add heat to the coolant flow in response to the coolant flow dropping below a minimum temperature, at least one outlet flow path to provide a portion of the coolant flow to at least one fuel processing subsystem, and a return flow path to return a remainder of the coolant flow to a storage tank. The coolant conditioning system is dynamically controllable to provide a portion of the coolant flow above a minimum temperature to reduce or prevent condensation of the reformate flow in selected components of the fuel processing subsystem that receive the portion of the coolant flow.
1. A coolant conditioning system for supplying a coolant to at least one fuel processing subsystem, the coolant conditioning system comprising:
a coolant storage tank;
a pump to supply a coolant flow, the pump including a pump inlet and a pump outlet;
at least one coolant preheater connected to a reformate flow to transfer heat from the reformate flow to the coolant flow, the at least one coolant preheater including a coolant inlet connected to the pump outlet and a coolant outlet;
a heater connected to the coolant outlet to selectively add heat to the coolant flow when the temperature of the coolant flow at the coolant outlet falls below a minimum temperature, the heater including a heater inlet for the coolant and a heater outlet for the coolant;
at least one outlet flow path to direct a portion of the coolant flow from the heater outlet to the at least one fuel processing subsystem; and
a return flow path to return a remainder of the coolant flow from the heater outlet to the storage tank.
2. The coolant conditioning system of claim 1 wherein the pump supplies the coolant flow at a desired flow rate.
3. The coolant conditioning system of claim 1 wherein the pump supplies the coolant flow at a constant flow rate.
4. The coolant conditioning system of claim 2 wherein a flow rate of the portion of the coolant flow under normal operating conditions is less than the desired flow rate.
5. The coolant conditioning system of claim 1 further comprising at least one pressure regulator downstream from the heater to maintain the portion of the coolant flow to the at least one fuel processing subsystem at a desired pressure.
6. The coolant conditioning system of claim 1 wherein the minimum temperature is the dewpoint temperature of the reformate flow.
7. The coolant conditioning system of claim 1 further comprising a temperature sensor to measure the temperature of the coolant flow exiting the preheater.
8. The coolant conditioning system of claim 7 wherein the heater is responsive to a signal from the temperature sensor.
9. The coolant conditioning system of claim 1 wherein the heater is an electric heater.
10. The coolant conditioning system of claim 1 further comprising a makeup flow path connected to the storage tank to provide additional coolant flow to the storage tank from a coolant source.
11. The coolant conditioning system of claim 10 wherein the coolant source is a recycle flow from a fuel cell system.