Recirculation system and supply system comprising said system
AssigneeArco Fuel Cells S.R.L.
InventorsAngelo D'Anzi, Pietro Mandurino
Life of this patent
Estimating the term…
Abstract
System for recirculating hydrogen in a fuel cell including a tank having an inlet connectable to an outlet of the fuel cell and an outlet connectable to a line for feeding hydrogen to the fuel cell; the recirculation system includes a first check valve and a second check valve; the first check valve can be inserted between the outlet of the fuel cell and the inlet of the tank, for adjusting a flow from the fuel cell to the tank whilst the second check valve can be inserted between the outlet of the tank and the hydrogen feed line, for adjusting a flow of hydrogen from the tank to the feed line.
Claims16
A hydrogen recirculation system for at least one basic fuel cell, having a first inlet side for a first reactant, hydrogen, and a second inlet side for a second reactant, said first inlet side including an inlet for the first reactant and an outlet for at least a first by-product, water, of a reaction which occurs in the at least one basic fuel cell,
- said recirculation system comprising a tank including an inlet configured to be connected to said outlet of the at least one basic fuel cell and a first outlet configured to be connected to a line for feeding said first reactant to the at least one basic fuel cell,
- said recirculation system comprising at least a first check valve, inserted between said outlet of the at least one basic fuel cell and said inlet of the tank, to allow or prevent a first flow from the outlet of the at least one basic fuel cell to the inlet of the tank and at least a second check valve, inserted between said outlet of the tank and the line for feeding the first reactant, to allow or prevent a second flow of the first reactant from the outlet of the tank to the line for feeding the first reactant,
- said first check valve being a one-way valve configured to:
- automatically open to allow the first flow from the outlet of the at least one basic fuel cell to the inlet of the tank when a pressure at the outlet of the at least one basic fuel cell is greater than a pressure at the inlet of the tank, and
- automatically close to prevent a flow between the outlet of the at least one basic fuel cell to the inlet of the tank when a pressure at the outlet of the at least one basic fuel cell is less than a pressure at the inlet of the tank, and
- said second check valve being a one-way check valve configured to:
- automatically open to allow the second flow form the tank to the line for feeding the first reactant when pressure at the outlet of the tank is greater than a pressure at the line for feeding the first reactant, and
- automatically close to prevent a flow between the outlet of the tank and the line for feeding the first reactant when pressure at the outlet of the tank is less than the pressure at the line for feeding the first reactant.
A process for recirculating an electricity generating plant comprising a stack of fuel cells having a first inlet side for a first reactant and a second inlet side for a second reactant, said first side including an inlet for a first reactant, hydrogen, and an outlet for at least a first by-product, said process comprising the steps of:
- putting in communication the inlet of the first reactant with a line for feeding the reactant using a feed valve, feeding the first reactant to the stack of fuel cells and keeping the stack of fuel cells at a working pressure;
- putting in communication the outlet of the stack of fuel cells with a tank using a first check valve which allows a flow of said first by-product from the stack of fuel cells to the tank;
- the first check valve being a one-way valve configured to:
- automatically open to to allow the flow of the first sub-product from the stack of fuel cells to the tank if the pressure at the outlet of the stack of fuel cells is greater than a pressure at the tank, and
- automatically close to prevent a flow between the outlet of the stack of fuel cells and the tank when the pressure at the outlet of the stack of fuel cells is less than the pressure at the tank, a pressure in the tank adapting to the working pressure;
- putting the tank in communication with the feed line, downstream of the feed valve and upstream of the stack of fuel cells, via a second check valve which is configured to:
- automatically open to allow a flow of gas from the tank to the feed line when a pressure at the tank is greater than a pressure at the feed line, and
- automatically close to prevent a flow between the tank and the feed line when the pressure at the of the tank is less than the pressure at the feed line,
- interrupting the feeding of the first reactant to the stack of fuel cells, closing the feed valve, in the presence of excessive water in the first inlet side of the stack of fuel cells, the interrupting of the feed determining a negative pressure upstream of the first check valve and downstream of the second check valve, said negative pressure determining a closing of the first check valve and an opening of the second check valve such that the second reactant, compressed in the tank, feeds the stack of fuel cells, said second reactant coming from the tank being consumed until reaching a minimum predetermined pressure value;
- after the step of interrupting the feeding of the first reactant, a step of opening the feed valve when the predetermined minimum pressure value is reached in the tank determining an overpressure in the feed line downstream of the feed valve, the overpressure in the feed line of the first reactant pushing, via the first reactant, the reaction by-product, water, present in the stack of fuel cells towards the tank.
Dependencies are inferred from the claim text.