{
    "title": "Desalination",
    "inventor_name": "James Tang; Joshua Zoshi",
    "publication_year": 2009,
    "device_name": "Thermo-Ionic Desalination System",
    "goal": "Produce fresh drinking water with dramatically lower energy consumption than conventional desalination methods.",
    "problem_addressed": "High energy use and carbon impact of existing seawater desalination technologies (evaporation-condensation and reverse osmosis).",
    "concept_summary": "The Saltworks process uses low-temperature heat to evaporate seawater, creating a high-salinity solution that stores concentration-gradient energy. This energy is harvested in a proprietary ion-selective device where polystyrene bridges, chemically treated to allow only specific ions, enable diffusion-driven migration of sodium and chloride from the concentrated stream into lower-salinity streams, thereby desalinating the target water. Only a small amount of electrical power is needed for low-pressure fluid circulation.",
    "detailed_description": null,
    "category": "Thermal Systems",
    "principles": [
        "Concentration gradient (osmotic) energy",
        "Ion-selective membrane diffusion",
        "Low-temperature heat utilization",
        "Voltage-driven ion migration"
    ],
    "scientific_domains": [
        "Chemical Engineering",
        "Environmental Engineering",
        "Thermodynamics"
    ],
    "mechanisms_of_action": [
        "Evaporation of seawater to increase salinity",
        "Creation of a concentration difference across ion-selective polystyrene bridges",
        "Diffusion of Na^+ and Cl^- ions from high-salinity stream to low-salinity streams",
        "Low-pressure pumping to circulate fluids"
    ],
    "materials": [
        "Polystyrene",
        "Ion-selective chemical treatments",
        "Saltwater (seawater)",
        "Concentrated brine"
    ],
    "energy_sources": [
        "Low-temperature heat (solar thermal or waste heat)",
        "Electrical energy for low-pressure pumps"
    ],
    "inputs": [
        "Seawater (or brackish water)",
        "Heat source (30-40  deg C)",
        "Small electrical power for pumps"
    ],
    "outputs": [
        "Fresh (desalinated) water",
        "Concentrated brine waste"
    ],
    "claimed_performance": "Up to 80 % less electrical/mechanical energy than leading desalination technologies; pilot plant uses roughly one quarter the energy of conventional plants; four-times less energy per litre of fresh water reported.",
    "experimental_evidence": "Proof-tested by the National Research Council of Canada and BC Hydro's Powertech Labs; a 1,000 L-per-day pilot plant in Vancouver is operational with chemical-free pre-treatment.",
    "replication_status": "Pilot plant built and running; testing performed by NRC Canada and BC Hydro Powertech Labs.",
    "keywords": [
        "Desalination",
        "Concentration gradient energy",
        "Ion exchange membrane",
        "Solar thermal",
        "Low-energy desalination"
    ],
    "related_technologies": [
        "Reverse osmosis",
        "Multi-stage flash distillation",
        "Solar thermal desalination",
        "Ion-exchange membranes"
    ],
    "controversy_level": "low",
    "confidence_score": 0.85,
    "practicability_score": 0.7,
    "fringe_score": 0.2,
    "evidence_strength": 0.6,
    "risk_score": 0.2,
    "trl_estimate": 6,
    "source_urls": [
        "http://www.saltworkstechnologies.com",
        "http://rt.com/Sci_Tech/2009-12-17/ions-trick-desalinate-water.html",
        "http://www.technologyreview.com/energy/24237/?a=f",
        "http://www.patentsview.org/patent/CA2649873"
    ],
    "organizations": [
        "Saltworks Technologies Inc.",
        "National Research Council of Canada",
        "BC Hydro Powertech Labs",
        "Sustainable Development Technology Canada"
    ],
    "applications": [
        "Municipal drinking water supply",
        "Agricultural irrigation",
        "Industrial process water"
    ],
    "limitations": [
        "Requires a low-temperature heat source (solar or waste heat)",
        "Performance improves in arid climates; less effective in humid regions",
        "Scale-up beyond pilot plant not yet demonstrated"
    ],
    "open_questions": [
        "Long-term durability of ion-selective polystyrene membranes",
        "Economic viability at commercial scale",
        "Energy balance under varying ambient temperature and humidity"
    ],
    "red_flags": [],
    "evidence_quotes": [
        "The technology employs an innovative Thermo-Ionic energy conversion system that uses up to 80 per cent less electrical/mechanical energy relative to leading desalination technologies.",
        "The technology has been proof-tested by the National Research Council of Canada and BC Hydro's Powertech Labs.",
        "A pilot plant of 1,000 litre a-day seawater is now fully operational at a harbour location in Vancouver, British Columbia.",
        "The process relies on concentration gradients, and the natural tendency of sodium and chloride ions to flow from higher to lower salinity concentrations.",
        "The plant is currently running on real seawater, and we're in the final stage of expanding it to a capacity of 1,000 liters a day."
    ]
}