Energy management strategy and recirculation-based architecture designs for electrodialysis system operation

Patent metadata

Field	Value
Publication number	US-2025066227-A1
Application number	US-202418750891-A
Country	US
Kind code	A1
Filing date	Jun 21, 2024
Priority date	Aug 21, 2023
Publication date	Feb 27, 2025
Grant date	—

Abstract

Novel design frameworks for designing electrodialysis (ED) desalination systems for purifying brackish water are provided herein. The design frameworks of the present embodiments include one or more energy management strategies, as well as recirculation-based system architectures. The design frameworks can be independent of each other, or can be used together. In some embodiments, the energy management strategy can include determining a capacity of a battery in communication with an (ED) system and imposing a charge power limit onto the battery to limit the charging rate of the ED system. The energy management strategy can be used in combination with the recirculation-based system architectures to improve efficiency of purification performed by these ED systems. These architectures can include hybrid architectures that operate in continuous flow, but provide a recirculation stream to mix the feed to achieve a desired salinity of the product stream.

First claim

What is claimed is:

1 . A method of energy management for electrodialysis desalination, comprising:
determining a capacity of a battery in communication with an electrodialysis (ED) system such that energy from the battery is able to be used to perform desalination; imposing a charge power limit onto the battery to limit the charging rate of the ED system such that the ED system operates at a lower power operating point than the capacity of the battery; charging the battery using an available solar power until the battery reaches its charge power limit; and charging the battery to approximately maintain the charge power limit while performing desalination with the remaining available solar power until the battery is fully charged.

2 . The method of claim 1 , further comprising using the available solar power for performing desalination after the battery is fully charged.

3 . The method of claim 2 , wherein the available solar power for performing desalination substantially increases after the battery reaches its charge power limit.

4 . The method of claim 1 , further comprising discharging the battery to perform desalination.

5 . The method of claim 4 , wherein discharging the battery occurs when the available solar power is insufficient to perform desalination.

6 . The method of claim 1 , wherein charging the battery and performing desalination occurs substantially simultaneously prior to the battery reaching its charge power limit.

7 . The method of claim 1 , wherein charging the battery occurs before starting to perform desalination.

8 . The method of claim 1 , further comprising applying a time threshold at which the battery is configured to begin charging.

9 . The method of claim 8 , wherein the time threshold is set to a same time as a time threshold of a previous day.

10 . The method of claim 8 , wherein the time threshold is set to a time immediately before a peak solar irradiance.

11 . The method of claim 8 , further comprising predicting the peak solar irradiance by measuring weather data.

12 . The method of claim 1 , further comprising predicting the available solar power to determine time taken to charge the battery.

13 . A system architecture for electrodialysis desalination, comprising:
one or more pumps in fluid communication with an electrodialysis (ED) stack, the ED stack having an inlet for receiving one or more feed streams and an outlet for receiving one or more outlet streams; a feed flowing a fluid to the ED stack via the one or more pumps; a controller in communication with the one or more pumps and the ED stack, the controller being configured to operate under time-variant control to adjust one or more of a flow rate or a voltage to the ED stack to use power based on availability of the power; and one or more valves disposed downstream of the ED stack to receive the one or more outlet streams, the one or more valves being configured to recirculate the one or more outlet streams to the one or more pumps.

14 . The system architecture of claim 13 , wherein an amount of fluid in the one or more outlet streams recirculated to the one or more pumps is based on at least one of a target concentration or a desired recovery rate of a product stream of the one or more outlet streams.

15 . The system architecture of claim 14 , wherein the amount of fluid in the one or more streams recirculated is calculated, using the controller, by taking the difference between an outlet concentration of the stack and a target concentration.

16 . The system architecture of claim 13 , wherein the recirculated outlet stream of the one or more outlet streams mixes with the feed stream to lower the total concentration of the fluid at the inlet.

17 . The system architecture of claim 13 , further comprising one or more check valves configured to direct the recirculated outlet stream of the one or more outlet streams to the one or more pumps.

18 . The system architecture of claim 13 , further comprising one or more positive displacement pumps disposed along the one or more outlet streams to control a pressure of the recirculated stream of the one or more outlet streams.

19 . The system architecture of claim 13 , wherein the controller is in communication with a battery that provides power to the ED stack.

20 . The system architecture of claim 19 , wherein the controller is configured to:
determine a capacity of the battery; impose a charge power limit onto the battery to limit the charging rate thereof such that the ED stack operates at a lower power operating point than the capacity of the battery; charge the battery using available solar power until the battery hits its charge power limit; and charge the battery at the charge power limit while performing desalination with the remaining available solar power until the battery is fully charged.

Assignees

• Massachusetts Inst Technology

Inventors

• Tran Jimmy T
• Brei Melissa
• Bessette Jonathan
• Pratt Shane
• Costello Jeffrey
• Winter V Amos Greene

Classifications

• C02F2103/08

  Seawater, e.g. for desalination · CPC title

• C02F2201/009

  Apparatus with independent power supply, e.g. solar cells, windpower or fuel cells · CPC title

• C02F2201/46115

  Electrolytic cell with membranes or diaphragms · CPC title

• C02F2201/4611

  Fluid flow · CPC title

• C02F2201/005

  Valves · CPC title