The major environmental impact of glass production is caused by atmospheric emissions from melting activities
- The combustion of natural gas and the decomposition of raw materials during the melting lead to the emission of CO2. This is the only greenhouse gas emitted during the production of glass.
- Sulphur dioxide (SO2) from decomposition of sulphate in the batch materials can contribute to acidification.
- Nitrogen oxides (NOx) due to the high melting temperatures and in some cases due to decomposition of nitrogen compounds in the batch materials also contribute to acidification and formation of smog.
- Evaporation from the molten glass and raw materials can cause release of particles into the atmosphere.
Other environmental issues are water pollution, the use of non-renewable natural raw materials such as sand and minerals, production of solid waste and emission of volatile organic compounds (used in production of mirrors and coatings).
Although a lot has already been achieved, such as the complete substitution of fuel to gas for the glass melting, further reductions in emissions of SO2, dust particles, NOx and CO2 are still the main environmental objectives for our flat glass activities. Minimising and controlling these emissions in an integrated way is a complex matter. The development of environmental techniques is still ongoing, and AGC Glass Europe actively participates in the dynamic process of developing new techniques.
Most of these technologies, however, have disadvantages as well as advantages. For example:
- Switching from heavy fuel to natural gas reduced CO2 and SO2, but increases NOx
- Some technologies that reduce NOx can cause an increase in CO2 when extra energy input is needed
- Technologies that reduce SO2 can produce non-recyclable waste
- Some technologies for reducing SO2 are not compatible with end-of-pipe de-NOx technologies
- Some technologies can affect the lifetime of the furnace or the quality of the glass.
A glass furnace runs 24/7 and cannot be stopped and cooled down during its lifetime (15-18 years). Most technologies can therefore only be installed during a furnace rebuild. At that moment we have to “Look Beyond” and make decisions for a long period.
This report covers the major activities of AGC: the Architectural Glass Division (including Upstream operations such as glass production and Downstream operations such as glass processing) and the Automotive Division. The environmental impacts of these divisions are different, as the glass processing and Automotive activities have lower atmospheric emissions than the Upstream operations.