Glass Waste Management

What Is Glass Waste?

The Definition

Glass recycling is the processing of waste glass into usable products. Glass waste should be separated by chemical composition, and then, depending on the end use and local processing capabilities, might also have to be separated into different colours.

Additional Information

Glass recycling has been common place since the 70’s saving millions of tons of glass from being landfilled every year. Due to it’s structure, glass does not deteriorate when reprocessed meaning 100% of the waste can be reclaimed. Recycling glass not only reduces the demand on raw materials but also requires less energy than creating it anew.


How is it recycled?

Once glass is collected and taken to be reprocessed, it is:

  • crushed and contaminants removed (mechanised colour sorting is usually undertaken at this stage if required)
  • mixed with the raw materials to colour and/or enhance properties as necessary
  • melted in a furnace
  • moulded or blown into new bottles or jars.


The Different Types Of Glass

We use many different types of glass in the UK, but at home we mostly use ‘soda-lime-silica’ glass for containers like bottles and jars. It is important not to mix up the different types of glass as they are re-processed differently.

Different types of glass include:

  • borosilicate glass – used for heat-resistant cooking equipment like Pyrex
  • lead glass – for sparkling decorative glassware
  • glass fibre – for insulation and fibre optic cable.

These different types of glass are not widely recycled so do not add these into your kerbside collection container or bottle banks at the recycling centre.

Colour and quality

During the glass manufacturing process, extra raw materials can be added to give the glass a particular colour or special qualities.

The extra raw materials that can be added are:

  • iron for a brown or green colour
  • cobalt for blue
  • alumina for durability
  • boron to improve resistance to heat or cold.
Glass Waste - How It's Recycled


Most frequent questions and answers

Glass bottles and jars are 100% recyclable and can be recycled endlessly without any loss in purity or quality. Over a ton of natural resources are saved for every ton of glass recycled. Energy costs drop about 2-3% for every 10% cullet used in the manufacturing process.

Glass recycling helps the environment. The amount of energy needed to melt recycled glass is considerably less than that needed to melt raw materials to make new bottles and jars. Recycling one bottle can save enough energy to power a television set for one and a half hours.

Broken glass is hazardous to the workers who collect and sort your recyclables. To dispose of broken glass, seal it in a box or wrap it in several sheets of newspaper and place it in your garbage.

The production and use of glass has a number of environmental impacts.

New glass is made from four main ingredients: sand, soda ash, limestone and other additives for colour or special treatments. Although there is no shortage of these raw materials as yet, they all have to be quarried, which can damage the landscape, affect the environment and use more energy.

Glass is 100% recyclable and can be endlessly reprocessed with no loss of quality.  Therefore by simply recycling our glass we can:

  • conserve non-renewable fossil fuels
  • reduce the emission of harmful gasses into the atmosphere.

The main problem with glass recycling is the quality of the glass collected. It can be contaminated, and therefore difficult to use in glass containers again. Due to the relatively low value of the material and the required processing costs, much glass ends up in aggregate where there is no environmental benefit.

To try to counter, this a split target has been put in place to limit the amount of glass that doesn’t go through a remelt process.

Supporting Documents

Supporting document created by the Recycle Now Organisation

Supporting Documents

Supporting document from Waste Source on Glass Waste Management

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