System and method for returning material from the Br
A flow battery system includes a first tank having a hydrogen reactant, a second tank having a bromine electrolyte, at least one cell including a hydrogen reactant side operably connected to the first tank through an ¾ feed and return system and a bromine electrolyte side operably connected to the second tank, and a crossover return system. The crossover return system includes a vessel operably connected to the ¾ feed and return system and configured to receive an effluent containing a first portion of the hydrogen reactant and a second portion of the bromine electrolyte, the vessel configured to separate the first portion from the second portion. A first return line returns the first portion of the hydrogen reactant to the first tank and a second return line returns the bromine electrolyte to the second tank.
1. A flow battery system, comprising:
a first tank including a hydrogen reactant;
a second tank including a bromine electrolyte;
at least one cell including a hydrogen reactant side operably connected to the first tank through an H 2 feed and return system and a bromine electrolyte side operably connected to the second tank; and
a crossover return system including (i) a vessel operably connected to the H 2 feed and return system and configured to receive an effluent containing a first portion comprising at least part of the hydrogen reactant and a second portion comprising at least part of the bromine electrolyte, the vessel configured to separate the first portion from the second portion, (ii) a first return line operably connecting the vessel to the first tank to return first portion comprising at least part of the hydrogen reactant to the first tank, and (iii) a second return line operably connecting the vessel to the second tank to return the second portion comprising at least part of the bromine electrolyte to the second tank.
2. The flow battery system of claim 1 , the crossover return system further comprising:
a sump operably positioned between the at least one cell and the second tank and configured to receive the effluent upstream of the vessel and separate a liquid phase portion, which comprises at least part of the bromine electrolyte, of the effluent from the first and second portions, the sump operably connected to the second tank to return the separated liquid phase portion to the second tank, and operably connected to the vessel and configured to move the first and second portions to the vessel.
3. The flow battery system of claim 1 , wherein the vessel includes a heat exchanger configured to remove heat from the effluent to condense the second portion into a liquid form.
4. The flow battery system of claim 3 , the crossover return system further comprising:
a compressor configured to increase a gas pressure of the effluent in the vessel.
5. The flow battery system of claim 4 , the crossover return system further comprising:
a pressure throttle operably positioned between the vessel and the first tank and configured to reduce an H 2 pressure of the hydrogen reactant flowing from the vessel to the first tank.
6. The flow battery system of claim 3 , further comprising:
a cooling loop operably connected to and configured to cool the heat exchanger.
7. The flow battery system of claim 6 , wherein the cooling loop is further configured to cool the at least one cell.
8. The flow battery system of claim 3 , the heat exchanger further comprising:
a thermoelectric cooling device configured to remove the heat from the effluent.
9. The flow battery system of claim 1 , wherein the vessel includes at least one gas-separation membrane having different fluxes for the hydrogen reactant and the bromine electrolyte and configured such that the effluent flows through the gas-separation membrane in the vessel and the gas-separation membrane separates the first portion from the second portion.
10. The flow battery system of claim 1 , wherein the vessel includes one of an adsorption surface and an absorption medium configured to selectively retain one of the hydrogen reactant and the bromine electrolyte to separate the first portion and the second portion of the effluent.
11. The flow battery system of claim 1 , wherein the vessel is pressurized to a pressure at which the second portion of the bromine electrolyte in the effluent condenses while the first portion of the hydrogen reactant remains in gas phase.
12. The flow battery system of claim 1 , wherein the vessel includes at least one complexing agent configured to react with the second portion of the bromine electrolyte to separate the first portion and the second portion.
13. A method of operating a flow battery system, comprising:
moving an effluent through an H 2 feed and return system from at least one of a first tank having a hydrogen reactant and at least one battery cell operably connected to the first tank into a vessel of a crossover return system, the effluent including a first portion comprising the hydrogen reactant and a second portion comprising a bromine electrolyte;
separating the first portion from the second portion in the vessel;
moving the first portion through a first return line to the first tank; and
moving the second portion through a second return line to a second tank.
14. The method of claim 13 , further comprising:
separating a liquid phase portion of the effluent from the first and second portions in a sump operably positioned between the at least one cell and the second tank, the liquid phase portion comprising the bromine electrolyte;
moving the first and second portions to the vessel; and
moving the separated liquid phase portion to the second tank.
15. The method of claim 13 , separating the first portion from the second portion further comprising:
removing heat from the effluent with a heat exchanger positioned in the vessel to condense the second portion from the first portion.
16. The method of claim 15 , further comprising:
increasing a gas pressure of the effluent with a compressor prior to moving the effluent into the vessel.
17. The method of claim 16 , further comprising:
reducing an H 2 pressure of the first portion moving from the vessel to the first tank with a pressure throttle positioned in the first return line.
18. The method of claim 15 , further comprising:
cooling the heat exchanger with using a cooling loop.
19. The method of claim 15 , further comprising:
cooling the heat exchanger with a thermoelectric cooling device.
20. The method of claim 13 , separating the first portion from the second portion further comprising at least one of:
moving the effluent through at least one gas-separation membrane in the vessel having different fluxes for the hydrogen reactant and the bromine electrolyte and configured such that the gas-separation membrane separates the first portion from the second portion;
moving the effluent through one of an adsorption surface and an absorption medium in the vessel configured to selectively retain one of the hydrogen reactant and the bromine electrolyte to separate the first portion and the second portion;
pressurizing the vessel to a pressure at which the second portion of the bromine electrolyte in the effluent condenses while the first portion of the hydrogen reactant remains in gas phase; and
combining the effluent with at least one complexing agent in the vessel configured to react with the second portion of the bromine electrolyte to separate the first portion and the second portion.