On March 9th 2016, the participants of the EM39-course set out on another excursion within the module “Waste Management & Circular Economy”. After a comprehensive introduction to the theoretical background and topics from recycling philosophy, waste collection and transportation, to treatment, landfill and life cycle assessment tools, the excursion provided a real experience of circular economy as a strong strategy for recycling.
“The beauty of glass recycling is that if you purchase a bottle, get backing to a recycling bin it will make another bottle.”
The first stop was the glass factory Glashütte Freital GmbH – where recycling plays a key role in the production process and about 70% of the source material originates from glass waste. Thereby the technology today allows us to sort glass in way that would not be economically possible if done manually. The first step is to remove small metal objects. Series of optical sensors proceed for identifying the glass by color, ejecting clear glass with air jets.
Recycled glass is mixed with soda ash, sand and limestone (as you would mix a cake!) – then everything is melted together in a very large furnace heated up to 2,700°C and turns to molten glass. The molten glass is cured to a process and thereupon delivered to a forming machine. There the glass being cut in to drops and gobs and forms immediately to a glass container. Afterwards will go through a lengthy inspection process automatically. Also to ensure consistent high quality, the composition of raw materials and products are constantly controlled in the laboratory.
The glassworks in Freital was founded in 1818 and provides ever since glass container for everyday use there. Thanks to Mr. Thomas Engler, the manager of the company, who welcomed and assisted the participants in exploring glass production and recycling. We were convinced at the end to have a new view on the glasses as he promised us before his presentation.
The course continued the excursion in the afternoon session to a hazardous waste pre-treatment facility of the Fehr Umwelt Ost GmbH. As a certified company it guarantees an environmentally sound disposal and recovery for hazardous waste in the district and takes care of everything from pick sorting and preparation to thermal treatment. The technician explained the sophisticated international labeling system for hazardous waste. Such hazardous waste must be stored in special containers, where according to their physical, chemical or toxicological properties, it must be pre-treated respectively. The participants learnt about some neutralization and detoxification procedures and were informed of some additional methods like sludge treatment.
Thanks to Frau Randt, the chemical engineer from the company, who kindly guided the participants throughthe different stages of the pre-treatment. At the end she also pointed to the incineration treatment unit as an integral part in hazardous treatment facilities, which consists mainly of air purification systems as the most costly part besides the furnaces.
Report & photographs by Mehri Sadat Alavinasab (Iran), with special acknowledgement for Dr. Dietmar Lohmann, Dr. Andre Lindner and for the CIPSEM group.