Glass can be recycled endlessly without losing any of its properties. Why, then, do most countries — with the exception of European countries — still send most of their glass to landfills? In 2018, the U.S. alone dumped nearly 7 million tons of glass in landfills, accounting for 5.2 percent of all municipal solid waste, according to the U.S. Environmental Protection Agency.
The push to reduce the use of plastic is accelerating the search for new materials, particularly for liquid containers. But glass is an already existing material that could be the star of a net-zero carbon economy.
Worldwide, glass production produces at least 86 million tons of carbon dioxide each year. But most of this amount can be almost wiped out when glass is recycled: existing technologies could turn glass production into a mostly carbon-free process. What needs to happen is for countries to stop sending glass to landfills and make glass recycling mandatory.
Glass is made by heating limestone, sand, and soda ash to about 1,500 °C. This heat usually comes from natural gas and accounts for between 75% and 85% of carbon emissions from glass production. The remaining emissions are a by-product of chemical reactions between raw materials. But some of these materials can be replaced with recycled glass (the so-called cullet).
When this glass is dissolved, no CO2 is released. The furnaces also do not have to reach such high temperatures to melt this type of glass as is the case for the melting of raw materials, offering additional carbon savings. According to the European Container Glass Federation (FEVE), an industrial group based in Brussels, putting 10% more recycled glass into a kiln reduces CO2 emissions by 5% compared to producing glass entirely from raw materials.
In glass recycling, Europe is the most advanced region in the world by a certain margin and has the ambition to be even better. The researchers were able to study how Europe’s recycling system came about, its strengths and weaknesses, and whether there are lessons for other countries. Three-quarters of the glass used for containers such as bottles are collected for recycling in all 27 Member States and the United Kingdom. As a result, the new glass produced in the European Union already contains around 52% recycled material. The glass container industry has set itself the goal of collecting 90% of all glass from containers in the EU by 2030.
Cover photo by Bobby Donald