Managing high salinity brines from geological carbon sequestration
The water-energy nexus has been heavily researched over the past decade, but there remain a surprising number of gaps in our basic knowledge of the linkages between these two critical systems for sustaining human wellbeing. This presentation will review those gaps and highlight emerging ones relevant to produced water from geological carbon sequestration. We find that the majority of saline brines produced during the carbon sequestration process will exceed 100,000 ppm total dissolved solids. Treating this water using state-of-the-art thermal methods, including mechanical vapor recompression and crystallization, would impose a significant (4-8%) energy penalty on the coal fired power plant, negating some of the benefits of carbon storage. Identifying the need for energy efficient high salinity brine treatment, we developed a novel, membrane-based approach for concentrating high salinity brines entitled Osmotically Assisted Reverse Osmosis (OARO). Finally, we perform a cost optimization of OARO configurations, demonstrating that while the cost optimal and energy optimal configurations are not equivalent for this system, the cost-optimal configuration for OARO dominates MVC on both cost and energy consumption metrics.
Associate Professor of Civil & Environmental Engineering and as a Center Fellow, by courtesy, in the Woods Institute for the Environment, Stanford University
At Stanford University, Professor Mauter is appointed as an Associate Professor of Civil & Environmental Engineering and as a Center Fellow, by courtesy, in the Woods Institute for the Environment. She directs the Water and Energy Efficiency for the Environment Lab (WE3Lab) with the mission of providing sustainable water supply in a carbon-constrained world through innovation in water treatment technology, optimization of water management practices, and redesign of water policies. Ongoing research efforts include: 1) developing automated, precise, robust, intensified, modular, and electrified (A-PRIME) water desalination technologies to support a circular water economy, 2) addressing the water constraints to deep decarbonization by quantifying the water requirements of energy systems and developing new technologies for high salinity brine treatment, 3) supporting design and enforcement of California agricultural water policy.
Mauter also serves as the research director for the National Alliance for Water Innovation, a $100-million DOE Energy-Water Desalination Hub (pending appropriations) to address water security issues in the U.S. The Hub targets early-stage research and development of energy-efficient and cost-competitive technologies for desalinating non-traditional source waters.