Why Isn’t Glass Being Recycled and Is It Really Sustainable?
Glass containers have been presented as being a sustainable alternative to plastics and other single-use materials because it is made from non-toxic compounds and has the ability to be continuously recycled. It also has a cheap price point. However, there has been some controversy around glass and how relevant it is to sustainability.
Glass is made from natural and abundant raw materials (sand, soda ash, and limestone) that are melted at very high temperatures to form the material. At high temperatures, glass resembles liquids, however at ambient temperatures, it behaves like solids. As a result, glass can be poured, blown, pressed, and molded into nearly any shape for any occasion.
It is a well-loved and well-used material. In 2018 alone, landfills received 7.6 million tons of glass through municipal solid waste (MSW). This was 5.2 percent of all MSW landfilled that year. While this number seems low, it has begged the question: why is glass not being collected and recycled at higher rates? What is so much glass doing in landfills, if it can be repurposed and endlessly reworked?
The Environmental Protection Agency (EPA) has combined data from the Glass Packaging Institute with information from state environmental agencies to measure the recycling rate of glass containers in the United States. The number of recycled glass containers was 3.1 million tons in 2018, for a recycling rate of 31.3 percent. Considering glass can be recycled indefinitely without losing its quality, this rate is low when thinking about sustainability goals. Compare this to Switzerland, which recycled 94% of their disposed glass in the same year!
Benefits of Recycling Glass
Recycling glass comes with many benefits. Firstly, it removes waste from the environment, including landfills. Manufacturers also benefit from recycling in several ways: recycled glass reduces emissions and consumption of raw materials, extends the life of equipment, such as furnaces, and saves energy. Recycling helps create a circular economy that is cost-effective and conservative rather than wasteful. Over a ton of natural resources are saved for every ton of glass recycled.
So, what is stopping the United States from achieving
a higher rate of glass recycling?
Research suggests that contamination of glass is the top reason and concern for this low recycling rate. Technology has come far, yet still has a long way to go, and contamination can cause an entire batch of recycled glass to go to waste. Contamination occurs, mainly, through the public which may not have a strong knowledge of what can be recycled.
Every recycling program is different, but usually only two types of glass can be placed in curbside recycling and public recycling bins: glass bottles and jars. Bottles include things like: beer, wine, food condiments, liquor, soft drinks, vinegar, olive oil, etc. Jars include: salsa, pickles, jam, applesauce, cherries, olives, honey, sauces, etc.
Contamination occurs when the glass or glass-like materials are mixed in with the previously mentioned recyclables. Items like mirrors, vases, dishes, pyrex, or other similar items can cause enough contamination that they can interrupt production, damage machinery, and also cause defective, weak containers. These items are typically not made with pure glass compounds, thus, cannot be recycled in the same way, if at all.
Contamination can also occur through improper preparation of glass due to recycling by the public. To prepare glass containers, they should be rinsed well to dispose of any excess food or liquid residue that could diminish the quality of the recycled glass used in production. Glass containers should not be thrown into recycling bins or sent off to recycling without first doing this step.
Another concern about recycling glass is when glass is mixed with other types of recycling materials it can be dangerous and difficult to remove broken glass from the recyclables.
Initiatives to increase public education on the benefits of glass recycling and the consequences of contamination should be prioritized by municipal waste and recycling programs if available. Many municipalities still struggle financially to create a pilot program for recycling in general, especially so for glass recycling. This is also a challenge for achieving higher recycling rates, as these efforts are left to state and municipalities rather than a federal approach.
In summary, glass recycling is not going away, and it may be more important now than ever for reaching sustainability goals. While glass is a sustainable, non-toxic, and abundant resource, there needs to be more curb-side recycling programs and other initiatives that support a closed-loop cycle of glass use. If your area doesn’t offer curbside glass recycling check to see if there are drop-off bins in your area. You may be surprised to find one on your typical route to the grocery store, gym, or work. Glass manufacturers actually need recycled glass to keep up with supply and demand trends, as it is more cost and energy-efficient than producing virgin glass.
Greater public education about glass recycling needs to be prioritized as well to minimize contamination. Meaning, from manufacturing to disposal, glass should be more optimized to reach its ideal sustainability potential.
