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Sorbents Workshop. RRT 3 Meeting Rehoboth Beach, Delaware May 18 th , 2011. NTTAA 1995. OMB Circular A-119 (Public Law # 104-113). ASTM Performance Standards. Adsorbents – F-726. Absorbents – F-716. Thickeners/Solidifiers – F-726/716. Types of Sorbents .
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Sorbents Workshop RRT 3 Meeting Rehoboth Beach, Delaware May 18th, 2011
NTTAA 1995 • OMB Circular A-119 (Public Law # 104-113). • ASTM Performance Standards. • Adsorbents – F-726. • Absorbents – F-716. • Thickeners/Solidifiers – F-726/716.
Types of Sorbents • Inorganicsorbents – include mineral products such as vermiculite, perlite, sand, clay (alumina silicates), activated carbon, pozzolanic rock. • All of these materials rely upon liquids coating surfaces, both external and internal. • Adsorbents by definition.
Organic Sorbents • Cellulosic and Synthetic materials. • Cellulosic – comprised of carbon elements, naturally occurring materials such as wood chips, feathers, ground corncobs, peat moss, cotton, diatomaceous earth, etc. • Adsorbent by definition.
Synthetic Sorbents • Comprised of carbon elements but man-made “surface-coating” materials such as polypropylene, polyurethane, polyethylene. • Adsorbent by definition. • Others – cross-linked polymers and rubber compounds that “swell” in liquids are Absorbents by definition.
History of “Modern” Sorbents • Polypropylene - adsorbent. • 1950s – Naval Research Labs – micro –filter applications. • 1960s – Exxon develops mb-pp process. • 1970s – Exxon patents & processes in place. 3M and K-C primary downstream marketers. • 1989 – Exxon Valdez boosts New Pig, SPC and dozens of others.
History (cont.) • Super-Absorbents Polymers (SAPs) • 1960s – P&G develop “water-sensitive” polymers (polyacrylates/polyacrylamides), to become known as “Pampers®”. • Revolutionize personal health care industry. • 1970s – Dow Chemical develops “oil-sensitive” polymers (alkyl styrene copolymers), to become known as Imbiber Beads®. • SAP unique to the entire sorbent industry.
History (cont.) • Solidifiers • 1960s – Shell Chemical invents styrenic block copolymers as hot-melt adhesives, asphalt additives, moulded thermoplastics, others. • 1992 – Exxon investigates use of polystyrene in combination with polybutadiene, polyisoprene (rubber) as a sorbent material. • 2003/2004 – Selection Guide “Alternative Response Technologies” & Pre-Approval for use.
“Miscellaneous Oil Spill Control Agent” • “Disclaimer: [Product Name] is on the U.S. Environmental Protection Agency’s NCP Product Schedule. This listing does NOT mean that EPA approves, recommends, licenses, certifies, or authorizes the use of [Product Name] on an oil discharge. The listing means only that data have been submitted to EPA as required by subpart J of the National Contingency Plan, Section 300.915. (Source: 40 CFR §300.920 (e))”
SAP/Solidifier Testing • 10 Solidifier Products • 1 oil-sensitive SAP. • Representative Test Liquids : • Mineral Spirits – household cleaning solvent. • SAE 10 W 30 – typical refined lubricating oil. • # 2 Diesel Fuel – aliphatic transportation fuel. • Gasoline – aromatic transportation fuel. • Xylene – aromatic BTEX-type solvent. • Note – crude oil very difficult to obtain.
Testing Criteria • To determine effectiveness of test Products to completely “immobilize” test Liquids within given time-frame. • To determine effectiveness of test Products to completely immobilize test Liquids using variable volumes of test Liquids. • Observable “free” liquids within test containers after time limit considered a failure. • Product/Liquid mix “slump” @ 15-30°angle considered a failure.
Benefits of Immobilization • Elimination of “free” liquids means: • Elimination of secondary contamination of personnel versus adsorbents. • Elimination of secondary contamination of the environment versus adsorbents. • Significant reduction of concentration-in-air of toxic and/or explosive vapors. • Concentration-in-air often to below LEL. • Waste disposal minimized.
Caribbean Petroleum RefiningPuerto Rico – Oct. 23rd, 2009 • Gasoline spill during loading operations. • Colourless? Where is it? • Explosive vapours? Toxic Vapours? • SOP – foam or evaporate/dissipate? • Toxicity Considerations - Fuels & solvents near urban centers?
Test Methodology • Product samples assigned Product Code #s. • Volume ratios of test product to volume ratios of test liquid determined at 1:1; 1:2; 1:4; & 1:8. • Test products added to test liquids to simulate spill application. • Test products allowed to stand for 3 hours @ 20° C / 68° F. • Note – Bulk density of test solidifiers approx. ½ of test SAP.
Observations • Solidifiers (Product Code #s 101, 102, 103, 104, 201, 202, 203, 205, 206) – Failed all tests @ all ratios with all test liquids. • Solidifier (Product Code # 204) • Failed all tests @ 1:8 volume ratio. • Immobilized Diesel Fuel & Mineral Spirits @ 1:4 volume ratio. • Failed on Gasoline & Xylene @ 1:4 volume ratio. • Failed on Xylene @ 1:2 volume ratio. • Immobilized Xylene @ 1:1 volume ratio. • Immobilized 4 remaining test liquids @ 1:1 & 1:2 ratios.
Observations (cont.) • Super-Absorbent Polymer (Product Code #301). • Failed to immobilize SAE 10W30 test liquid @ all volume ratios. • Immobilized gasoline, xylene, diesel fuel & mineral spirit test liquids at all volume ratios. • “Swelling”of SAPs means they will absorb several times their volume of liquids.
Considerations • All solidifiers are not created equal. • All of the solidifiers dissolved to varying degrees in excess liquid as per ASTM specs. • Particle size played a role in the speed of the reaction. • Aggressive solvents such as gasoline and xylene were more difficult to handle. • The SAP was able to immobilize several volumes of solvent due its swelling, as per ASTM specs.
Summary Statement • 1989 Exxon Valdez – recovery rates 10 – 15% • 2010 Deepwater Horizon – recovery rates 10 – 15%. • Heavy reliance on disposal technologies such as dispersants and in-situ burning. • Chemical recovery almost non-existent. • Failure of mechanical recovery techniques to adapt and look for innovations. • Time for change?
“You must be the change you want to see in the world”(Mahatma Ghandi,1869 – 1948) Thank You for Your Interest.