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Household Pollutants

There are two household Pollutant Collection Events each year, where you can take household substances that may be harm the environment if poured down the drain, into a storm sewer or tossed into the trash.

Among the products that can be disposed of safely are pesticides, paints, cleaners, batteries, yard-care products, acids, caustics, thinners, household flammable liquids, oil, antifreeze, bullets (50-caliber and smaller), and smoke alarms.
http://www.tulsarecycles.com/

Pros and cons
Properties of fly ash are much like those of calcium carbonate but with significant differences. Fly ash is essentially finely powdered sand but without sharp edges like calcium carbonate. The ash consists of small balls‹mostly solid, some hollow (1%). The hollow-sphere fraction has accounted for the main plastics uses up to now‹liquid coatings and molding compounds. Trelleborg Fillite, Inc., Norcross, Ga., is a unit of a British firm that is reputed to be the world's largest supplier of hollow fly-ash spheres.

The spheres add stiffness and compressive strength to plastic compounds, but at the expense of increased brittleness. On the other hand, some processors who use ash say the spheres act like small ball bearings to improve throughput. Fly ash also comes in an amorphous, non-spherical form, which is of little current commercial use.
http://www.plasticstechnology.com/articles/199909cu4.html