Glass

Definition

Recyclable glass is made up of :

• Industrial glass originating from professionals (bottling plants, wine merchants, restaurateurs,  mirror manufacturers,...)

• Glass from building and demolition sites

• Automobile glass from garages and scrap vehicles

• Household glass representing 13% of the weight of household waste

Figures

Regulation

The law of 13th July 1994 relating to industrial and commercial packaging waste makes collection of glass packaging obligatory, due to their recycled value.

Consequently, industrials must :

• Sort and store glass packaging in clean conditions in preparation for their future recycling

• Recycle glass packaging, either by their own means or by outsourcing to a sub-contractor

The law of 1st April 1992 relating to waste packaging from households make each manufacturer producing packaged goods for public sale responsible for contributing to, or providing facilities for, the removal of all its waste packaging.

Three options are open to these industrials :

• Implementation of a policy of deposit on return of their packaging

• Organisation of the collection of their packaging for recycling purposes

• Outsourcing their responsibilities to other organisations approved by public bodies

Treatment

Collection

The quantity of glass collected in the year 2000 was in the region of 1.7 million tonnes, of which :

• 150,000 tonnes was of industrial origin

• 1,555,000 tonnes were sorted from household waste

The increase in household waste community sorting schemes is remarkable because it accounts for 90% of all glass collected nationwide.

Over the past 20 years, the sorting of household waste has multiplied by 15, resulting in the current rate of collection of 50% of all glass packaging. This increase in yields collected has been the result of increased awareness amongst the population and in particular in the increase in the number of recycling containers and optimisation of their location. Over the long term, this will also result in improved quality of recycled glass with better sorting by colour.

Recycling of materials

Once collected, the glass can be re-used or recycled :

 Deposit on return

Returned glass packaging can be re-used after sorting and cleaning.

Deposit on return accounts for 20% of all bottled products.

Recycling

Glass can also be 100% recycled, an indefinite number of times, , which means that everything collected is recycled, every time.

Once collected, sorted, cleaned and crushed, the glass is transformed into cullet and delivered to factories under certain conditions in accordance with specifications set out by the Chambre Syndicale des Verreries Mécaniques de France (Union of French Mechanical Glass Manufacturers). Cullet today accounts for an average of 50% of glass manufacture and

French output alone is sufficient to provide all the cullet for all glass manufacturers needs for making hollow glass packaging in France.

Certain more technical glass products designed for specific uses (laminated windscreens, de-icing rear windows, computer screen glass....) contains materials that are difficult to separate and are covered in thin deposits of chemical products making treatment of them difficult. Some pilot organisations have set up centres to treat these types of glass in order to provide users with the required quality of cullet.

For laboratory-produced glass, there are also recycling possibilities (borosilicate glass can be used to manufacture glass wool, sodiocalcic glass is compatible with household glass and can be recycled in the same way).

Other recycling possibilities are undoubtedly yet to be invented or developed.

Technical aspects

Melting the collected and recycled glass in the form of cullet in glassmakers’ industrial furnaces gives the best caloric yield. This primary material’s main secondary characteristic is that it melts more rapidly than raw materials (silica, lime, soda...).

Thus, each tonne of cullet included in the melting process enables the melting point temperature to be reduced by around 30% and so saves the equivalent of 100 kg in petrol of which 40 kg to melt the glass and 60 kg by avoiding the extracting, manufacturing and transportation process for new raw materials.