Those of us who recycle often have certain questions. Glass bottles are consumed worldwide in large quantities, especially in bars. Therefore, recycling them is essential. The question that arises is, how are glass bottles recycled? What happens to them? Furthermore, whenever we go to the green recycling bin, we see the warning not to put glass or ceramics in it. Why is this?
All these questions and more will be answered throughout this post. So, if you want to clear up your doubts once and for all, just keep reading
Throw glass in green container
Let's start with some of the mistakes many people make when recycling glass. They throw away glass cups thinking they're all the same. A glass or a tumbler isn't made of the same materials as a bottle. The main difference between these two objects is the lead oxide content of the glass.
This lead oxide is responsible for the fact that glass cannot be melted in the same furnaces in which glass bottles are melted for recycling. Therefore, to facilitate recycling and the use of materials, it is recommended that only glass be deposited in the green container.
Crystal is a glass composition that contains high concentrations of lead oxide. This is done because it gives the characteristic shine and sound of crystal. The more sound and shine a glass has, the more lead oxide it contains.
The law limits the concentration of heavy metals in glass bottles to 200 parts per million. This is why glass often appears to be of lower quality, with less shine and sound. However, thanks to this low concentration of heavy metals, it can be melted down and recycled.
If we do not recycle glass properly and put it in the green container, it will end up in the same ovens as glass and will become polluting gas emissions or become part of other bottles.
Problems in the recycling of glass bottles
Thanks to the small hole in the green bin, citizens are guaranteed not to make any big mistakes when recycling. It is important that recycling campaigns continue to educate people about caring for the environment so that they can appreciate what they are doing.
Few glasses and cups are made from glass. Furthermore, nowadays barium oxide is used in their manufacture, not lead oxide. This isn't dangerous in the long run, but it does make recycling glass bottles considerably more difficult. There are far worse materials that further complicate the process, such as the tubes from televisions and monitors.
Some examples of materials that contain glass but cannot be recycled in the green container are:
- A car windshield, which is made up of several layers, including a polymer one.
- Glazing with glass coatings to reflect UV rays.
- Stained window glass.
- Old television tubes and computer monitors, due to its high content of lead and phosphorus oxides.
How glass is recycled
When we leave a glass bottle in the green bin, the process begins with the collection of the material and its transport to a treatment plant. Here, an attempt is made to recycle 100% of the material, which makes glass stand out as one of the most efficient materials to recycle.
Glass is recyclable indefinitely without losing its physical characteristics, which makes it a great ally against plastic. Throughout the process, glass undergoes several steps to eliminate impurities and maximize the use of waste:
- Non-recyclable materials such as corks, stones, plastics and ceramics are eliminated.
- It is passed through magnetic separators that remove any metal.
- The glass is screened and crushed.
- The glass is checked by KSP machines that detect impurities using light and expel waste using jets of water or air.
The resulting clean glass is called cullet , and it is the raw material for making new bottles with lower energy consumption compared to creating glass from scratch.
Advantages of recycling glass bottles
Recycling glass bottles offers multiple environmental and economic benefits. By recycling glass:
- We reduce energy consumption since the calcine melts at lower temperatures than the original raw materials.
- We reduce CO2 emissions by up to 53% compared to manufacturing glass from scratch.
- We preserve natural resources such as sand, limestone and soda, preventing its extraction.
- We contribute significantly to the circular economy, where products are renewed instead of becoming waste.
Furthermore, glass recycling generates less solid waste, meaning less waste ends up in landfills. In 2019, 800.000 tons of recycled glass prevented the emission of more than 500.000 tons of CO2 and the use of more than 1 million tons of raw materials.
For all these benefits, glass recycling is key in the fight against climate change and in launching a truly circular economy. While there is still work to be done, every small gesture counts to protect our environment and ensure a more sustainable future.