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Activated Metal Treatment System for Paints
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NASA's Solution
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PCBs have been shown to cause cancer in animals and to have other adverse effects on the immune, reproductive, nervous, and endocrine systems. Although production of PCBs in the United States has been banned since the late 1970s, many surfaces are still coated with PCB-laden paints. The presence of PCBs in paints adds complexity and expense for disposal. Some treatment methods are capable of removing PCBs from surfaces, but these technologies create a new waste stream that must be treated. Other methods, like incineration, can destroy the PCBs but destroy the painted structure as well, preventing reuse. To address limitations of current treatment methods, researchers at NASA's Kennedy Space Center and the University of Central Florida have developed the Activated Metal Treatment System (AMTS) for Paints.
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| How It Works |  |
NASA's technology consists of a solvent solution (e.g., ethanol, d-limonene) that contains a catalyzed zero-valent metal. The metal component can consist of either a single metal or a bimetal (e.g., magnesium coated with small quantities of palladium). AMTS is first applied to the painted surface using either wipe-on or spray-on techniques. The solution then extracts the PCBs from the paint. The extracted PCBs react with the micro-scale, activated metal and are degraded into benign by-products.
| Benefits | |
- Effective—has been shown in lab- and field-scale tests to remove approximately 80% of PCBs from paint (three layers in thickness with initial PCB concentration as high as 700 parts per million) within 4 hours and approximately 100% of PCBs within 48 hours.
- In situ—treats PCBs in place, versus traditional abatement methods that generate a secondary waste stream. These secondary waste streams are also subject to potential regulation under the Toxic Substances Control Act (TSCA).
- No impact to structure—does not affect the material beneath the paint and allows for the surface to be repainted/reused or recycled following application.
- Cost-competitive—requires none of the costs associated with placing a building under vacuum; or transporting, treating, and/or disposing of a secondary waste stream. Preliminary estimates indicate that AMTS could cost between $15 and $17 per square foot for materials (not including labor). In addition, total costs (materials plus labor) are expected to be less than comparable costs for media blasting.
- Safe—produces harmless by-products.
- Versatile—can be used as a "wipe-on/wipe-off" method for in situ applications or as an immersion method (e.g., for dismantled parts awaiting disposal).
| Commercial Uses | |
According to the Environmental Protection Agency, over 1.5 billion pounds of PCBs
were produced in the United States before production ended in the late 1970s. Because
of their flame-resistant and insulating properties, PCBs were frequently added to paints
used on buildings, ships, and other structures. As these paints deteriorate or chip away, they present human and environmental health issues. AMTS represents a safe and cost-effective method for dealing with this problem.
In addition to treating painted surfaces, AMTS is applicable for other PCB-contaminated materials. For example, this technology can be used to remove/destroy PCBs that may be found in older caulking and other adhesive materials. AMTS is also applicable for treating concrete surfaces that have been contaminated by PCB-laden transformer oil. Other applications of AMTS may involve treating materials that are slated for disposal (or recycling), including the following:
- Electrical transformers
- Capacitors
- Transformer oils
- Waste oils
- Waste clothing
- Soils (ex situ)
- Other debris
PCBs in the above materials are frequently treated through incineration; however, AMTS could be used with an ex situ immersion process in lieu of incineration or other treatment techniques.
| Technology Development | |
AMTS has been tested extensively in laboratories at NASA's Kennedy Space Center. Click here for information on laboratory studies.
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