{
    "title": "Conversion of Waste Plastics Material to Fuel",
    "inventor_name": "David McNamara; Michael Murray",
    "publication_year": 2012,
    "device_name": "CYNAR Plastic-to-Oil System",
    "goal": "Convert end-of-life plastic waste into high-quality diesel/aviation fuel with high efficiency and low sulfur content.",
    "problem_addressed": "Large volumes of plastic waste ending in landfills and the need for sustainable alternative fuels for transportation and power generation.",
    "concept_summary": "The CYNAR process melts waste plastic and subjects it to oxygen-free pyrolysis, producing a mixture of hydrocarbon gases. Long-chain gases condense on plates in a contactor and are returned for further cracking, while short-chain gases proceed to fractional distillation, yielding diesel-grade fuel. Residual gases are recycled to heat the pyrolysis chamber, and the only solid by-product is a small amount of char.",
    "detailed_description": "Waste plastic is fed via a hot-melt in-feed system into a cylindrical pyrolysis chamber heated to 370-420  deg C in an oxygen-free atmosphere. The molten plastic vaporizes; pyrolysis gases travel upward into a contactor vessel containing sloped stainless-steel plates that act as condensers. Long-chain hydrocarbons condense on the plates and drip back into the chamber for additional thermal degradation, while short-chain gases exit the contactor and enter a fractional distillation column, producing a hydrocarbon distillate equivalent to petroleum diesel. The distillate is further refined in a vacuum distillation tower to meet fuel specifications. Syngas generated in the pyrolysis is scrubbed and fed back to the furnace to supply heat, improving overall energy efficiency. Char produced (~5 % of feedstock) can be used in construction materials. Each plant can process ~20 t of plastic per day, yielding up to 19 000 L of diesel.",
    "category": "Chemistry & Chemical Processes",
    "principles": [
        "Thermal pyrolysis",
        "Condensation of long-chain hydrocarbons",
        "Fractional distillation",
        "Heat recycling via syngas combustion"
    ],
    "scientific_domains": [
        "Chemical engineering",
        "Materials engineering",
        "Energy engineering",
        "Environmental engineering"
    ],
    "mechanisms_of_action": [
        "Thermal cracking of polymer chains",
        "Phase separation by condensation",
        "Fractional distillation of hydrocarbon vapors"
    ],
    "materials": [
        "End-of-life plastic (mixed polymer waste)",
        "Stainless steel (condensor plates)",
        "Char (carbonaceous solid by-product)"
    ],
    "energy_sources": [
        "Syngas combustion (internal furnace heating)"
    ],
    "inputs": [
        "Waste plastic feedstock",
        "Thermal energy (from syngas combustion)"
    ],
    "outputs": [
        "Diesel/aviation-grade fuel",
        "Char (used in construction)",
        "Syngas (re-circulated for heat)"
    ],
    "claimed_performance": "Up to 19 000 L of diesel per 20 t of plastic per day; ~5 % char by-product; fuel claimed to have higher efficiency and lower sulfur than conventional diesel.",
    "experimental_evidence": "Pilot plant operating capacity demonstrated; a single-engine aircraft flight powered solely by CYNAR-produced diesel was planned for July 2013; multiple waste-recycling firms have adopted the technology.",
    "replication_status": "Technology incorporated into several worldwide waste-recycling firms and under joint research with Loughborough University.",
    "keywords": [
        "plastic waste",
        "pyrolysis",
        "diesel fuel",
        "aviation fuel",
        "waste-to-energy",
        "CYNAR",
        "thermal cracking"
    ],
    "related_technologies": [
        "Pyrolysis reactors",
        "Liquefaction of plastics",
        "Fractional distillation columns",
        "Syngas utilization"
    ],
    "controversy_level": "low",
    "confidence_score": 0.9,
    "practicability_score": 0.8,
    "fringe_score": 0.1,
    "evidence_strength": 0.5,
    "risk_score": 0.2,
    "trl_estimate": 7,
    "source_urls": [
        "http://www.gizmag.com/fuel-plastic-waste-sydney-london-flight/26391/",
        "http://www.telegraph.co.uk/news/newstopics/howaboutthat/9889896/Pilot-attempts-first-flight-powered-only-by-household-plastic-waste.html",
        "http://www.cynarplc.com/cynar_technology.asp"
    ],
    "organizations": [
        "Cynar PLC",
        "Loughborough University"
    ],
    "applications": [
        "Aviation fuel",
        "Diesel fuel for vehicles and generators",
        "Construction material (char)"
    ],
    "limitations": [
        "Requires high-temperature pyrolysis equipment",
        "Energy balance depends on efficient syngas recycling",
        "Feedstock composition variability may affect fuel quality"
    ],
    "open_questions": [
        "Long-term operational stability and maintenance costs",
        "Full life-cycle environmental impact compared with conventional recycling",
        "Economic feasibility at larger scales"
    ],
    "red_flags": [],
    "evidence_quotes": [
        "Each Cynar plant can produce up to 19,000 liters (around 5,000 US gallons) of fuel from 20 tons of ELP per day.",
        "The only waste material left over from the ELP-to-diesel conversion process is roughly five percent char.",
        "The diesel produced by this method is actually claimed more efficient and lower in sulfur than generic diesel.",
        "Cynar's tech is being incorporated into several worldwide waste recycling firms, enabling such companies to convert ELP into diesel themselves.",
        "The pilot will be the first time the diesel produced by Cynar's recycling process has been used to power an airborne journey."
    ]
}