A New Solution to California's Energy and Water Challenges: Reducing the Cost of Desalination and Increasing Water Reuse
Reducing the Cost of Desalination and Increasing Water Reuse
Lawrence Livermore National Laboratory
Recipient
Livermore, CA
Recipient Location
7th
Senate District
16th
Assembly District
$999,040
Amount Spent
Completed
Project Status
Project Result
Project is complete. Recipient developed and tested a new operation mode of electrodes (called batch mode) and cell modules before deployment to Delta Diablo. Results show the potential to meet salt removal and productivity targets, while reducing flow efficiency losses caused by undesired mixing of desalted water and feed water. Using the optimized electrodes, the recipient demonstrated the ability to achieve desalination targets of 500 parts per million(ppm) total dissolved solids (tds) removal with more than 70% water recovery on Delta Diablo water samples. The recipient evaluated a novel charging circuitry design that takes advantage of the large inherent capacity of the cells to eliminate the need for AC-DC converters, thus simplifying the design and lowering cost.
The Issue
Desalination is currently the primary method of removing salt from industrial and municipal wastewater for reuse. However, this technology is energy intensive and expensive. Industrial processes and household activities continuously add salt to water, and as a result, the salt content of industrial and municipal wastewater is often too high for reuse. The salt content of this wastewater must be reduced to enable recycling and to avoid ecological damage, however a more energy efficient technology compared to current practice is needed.
Project Innovation
This project is demonstrating a flow-through electrode capacitive desalination (FTE-CD) technology to reduce the energy used to remove salt from wastewater. This advanced technology removes salt from water by applying an electric field to two porous electrodes. The electrodes act like a magnet for salt while the field is applied and remove the salt from water that flows through the electrodes using less energy and less costly than reverse osmosis (RO). Energy use of an FTD-CD system is projected to be 50% less compared to the energy use for an RO system. The recipient is partnering with two water districts to test the use of FTE-CD devices to desalinate wastewater from industrial and municipal sectors and determine how this small, flexible device can improve the energy and operating efficiency of wastewater treatment solutions for communities. Energy use and performance are being measured, while fouling and other operation issues are being identified.
Project Goals
Project Benefits
The FTE-CD technology has the potential to reduce the cost and energy associated with desalinating low to moderate salt content water and will represent an advancement over current RO technology. This technology has the potential to increase water recycling and reuse at the community or industrial level, which reducing the need to procure and transport fresh water sources. The advanced FTE-CD technology is small, flexible, and can be customized to the scale needed for each community or industry, thereby increasing a community's water reuse potential and drought resilience for the state.
Affordability
By reducing the cost of desalination by 30% or more, the cost of water reuse may become attractive compared to the cost of purchasing water and disposing of waste water.
Environmental Sustainability
By reducing the cost of desalination by 30% or more, the cost of water reuse may become attractive compared to the cost of purchasing water and disposing of waste water. An increase in reuse means that less potable water overall is used, increasing drought resilience.
Key Project Members
Michael Stadermann
Patrick Campbell
Subrecipients
The Leland Stanford Junior University
