Alternate Uses for Glass

Recycling glass has several benefits. New molten glass has just as many uses as the original - there is no loss of quality. Because glass is recycled at lower temperatures than are required to make new glass from raw materials, considerable energy savings (and therefore cost savings) can be realized. It's good for the environment because it reduces the requirement for raw materials, and reduces the use of landfills.

Cullet (crushed glass) can have many uses, the first of which is the most obvious - it is mixed with soda ash, sand and limestone, and put into a furnace, creating new molten glass. This can then be used to make new bottles and jars.

glass cullet

But cullet can be used in many other ways, such as:

  • as either base or surface coat (when mixed with asphalt) for roadways
  • as an additive to clay for brick-making
  • as an aggregate fill for moisture drainage; it can also be used in this way to filter water
  • for use in making spun glass fiberglass filaments for insulation
  • for "foamglass" - a cellular form of glass used for insulating and moisture resistance, similar to other insulation; it can also be used for oil spill cleanup
  • to make "glasscrete", a cement-based composite which contains glass
  • for use in hydroponics, as a growing medium for soil-less gardening
  • as a landfill cover
  • in pressed glass, for tableware, giftware, and the like
  • in sand traps on golf courses
  • to make glass mosaic tiles and synthetic marble
  • as utility bedding and back fill, particularly around underground pipelines and cables—it is easier to work with than sand when wet

Another American company, Andela Products Ltd., has created a "Glass Pulverizer System" for turning all types of glass into sand and gravel that has no sharp edges. It has the added bonuses of being able to use all types of glass, including windows and ceramics (which cannot be made into new molten glass), and of separating other contaminants, such as trash, at the same time as it crushes, therefore not requiring pre-sorting. This pulverized glass also has many uses, including:

  • a base for unpaved roads when mixed with soft clay soil
  • an underlay for walking trails
  • in dirt parking lots to keep dust down—it is even safe enough to walk on barefoot!
  • for filtration
  • and many of the same uses as the cullet (see above)

So, anything sand is used for, cullet can be used for. Not surprising when you consider that glass is made from sand. There are even some applications where cullet is superior to sand!

[Source: WasteWatch, March 2003 ]