(512a) Halophyte Biochar for Water Desalination Brine Concentrate Management

Disposal of concentrate from brackish water desalination is limited by concerns of salt leaching into and contaminating surface and ground waters. These concerns, and measures to prevent leaching, add substantially to concentrate disposal costs with little or no opportunity to recover those costs. One option being explored is the use of concentrate as irrigation water for producing halophyte biomass for forage and other applications. Continuing development of this option requires more knowledge about what happens to the salt in the concentrate once land applied as irrigation water.

The purpose of this project is to determine how much of the salt taken up by the halophyte crops can be protected from leaching by pyrolysis of the biomass, i.e. to determine the potential of sequestering salt in mineral form. Results from this research will be useful for those managing high salinity biomass streams, such as halophyte crop wastes and animal manures, and those seeking local concentrate disposal options with a potential for producing economic and/or environmental returns. The ability to sequester salt in biochar would decrease the negative impacts of land-applying high-salinity materials, including those used in desalination concentrate management systems.