Texas Company Has Many Uses for Recycled Glass
January 19, 2012
Recycled glass is a nightmare. Since the advent of single stream recycling (consumers put all recyclables in one container, the sorting is done at a MRF) the lowest profit item for recycle companies is glass.
The problem is that glass is heavy (more shipping cost), not very valuable (new glass is cheap) and it breaks into small pieces that get everywhere in the waste stream. Breakage also compounds the biggest obstacle to value, glass needs to be sorted by color to have significant value to companies that use recycled glass.
But there is company in Houston, Strategic Materials, that recycles more glass than any company in the world. They started over 100 years ago recycling plate glass from manufactures. Back then it was easy; the glass all about the same color and thickness and it was a simple “pile and grind” operation.
But for the last decade, as single-stream recycling came on line, Strategic Materials had to reinvent the way to recycle glass. They buy it by the ton from municipalities and it arrives in this unrecognizable pile of glass shards and trash. The piles go through several sorting processes to remove the dirt, paper and plastic, which represents about 40 percent of the weight of what they bought.
When the pile is mostly just glass, they start taking it over to their super-secret sorting building. This is the heart of their enterprise and the reason they lead the world in recycling glass. A series of optical sorters and other techniques separates the glass out by color. Outside the plant are these beautiful piles of “cullet,” the name for crushed, recycled glass in the marketplace.
The main buyer of their cullet are bottling plants (one of the largest in the country is the Owens Corning plant in Waco) and fiberglass manufactures (Owens Corning has a massive plant in Waxahachie). They include a portion of recycled glass into their production to cut costs; recycled glass requires must less energy (heat) to use.