German MRF trial shows bags of potential
Renting out a German MRF for the day doesn't come cheap, but one technology supplier wanted to demonstrate that mechanical sorting of residual black bag waste yields good returns. Dean Stiles travelled to Munich to find out more
German black bag waste is the residue after separate collection of packaging, paper, glass, kitchen and green waste, and is often considered fit only for production of refuse-derived fuel and compost. "This is the first time that we have had independent assessment of sorting this type of waste," says Jürgen Hüskens, TiTech's business development manager. "We can now show that high-quality materials can be recovered from a mixture of dry packaging and dry residual waste."
The WeSoTech plant used for the test typically handles a mixture of municipal, C&D and C&I waste. For the two-day trial, a bag shredder was installed and the installation set up to handle 300 tonnes of municipal solid waste collected from the nearby town of Freising. During the test, 180 tonnes of residual black-bag waste was processed using the plant's mechanical and manual sorting systems - the reduced amount sorted was due to technical issues at the plant during the test.
The test showed that almost 15% of the residual black bag waste contained recyclable plastics, paper, wood, and metals; by weight it showed 2% metals, 4% paper, and 4% wood (see table on page 14). The main target materials were ferrous and non-ferrous metals, film, PET, HDPE and PP, beverage cartons, and mixed paper.
As part of the trial, the recovered materials were sent on to processors across Europe for evaluation - very few German processors will accept material from contaminated waste.
TiTech plans to make the evaluations public once the information has been collated. If these figures are extrapolated across Germany for all black-bag waste, an additional 1.2M tonnes of wood, paper and metal could be recovered annually.
A two-day conference also ran alongside the trial. Here keynote speakers from Germany strongly defended orthodox German-thinking on packaging waste collection as set out in the German Packaging Ordinance (GPO), which came into effect in 1998. To meet GPO requirements, the country operates a separate collection system for packaging waste. Called the dual system, the second system operates parallel to municipal waste collection and disposal systems (see box).
"In the past few years, no other achievement of the dual system's introduction has been discussed with such controversy as separate collection," says Sascha Schuh from Ascon, the waste management consultancy firm that organised the conference in conjunction with TiTech.
He explains further: "The number of different garbage cans in German households has been on the rise in recent years. Depending on region and colour, blue, grey, yellow and brown cans have been piling up in individual houses, each waiting to be picked up according to its contents. Waste separation is carried out by the consumer. For a long time, this was viewed as the only way to collect light packaging, as a valuable and recyclable raw material, separately from normal household waste and recycle it in a high-quality manner."
Schuh feels that the trial and conference questions whether separate gathering and collection is still up to date. "The final assessments from the processors will determine the quality of the materials recovered by sorting instead of being picked up, bit by bit at households. This is an approach by which the packaging ordinance could develop into a recyclable material ordinance, which would optimise material separation and recycling in the joint collection of dry household waste and light packaging."
But this view runs contrary to orthodox German thinking. "Separate collection is the basis of the packaging ordinance and is example for Europe to follow," asserts Clemens Stroetmann, former state secretary in Berlin. He recognises that the ordinance does not specifically require separate collection, but any change would involve huge costs.
"Technology can play a larger role in waste collection and recycling, but in the end costs are important and investment in new plant will make any change cost prohibitive," he argues. He also believes there are social implications in
making changes to the system and removing the role of the citizen in recycling. "We know that 94% of German citizens think they are doing something for the environment when they recycle. And 95% see recycling of their waste as a
personal contribution towards environmental care," he says.
Dr Thomas Probst of bvse eV, the Bonn-based waste management advisory association, expresses similar doubts about the potential for Germany to change its approach towards packaging material collection.
"We get very good results for mixed dry waste and, while modern sorting technology clearly works, separate collection produces a much higher-quality recyclable material. Furthermore, there is a widespread consumer support for separate collection. And the yellow bin [German household dry recyclable packaging collection bin] is part of the German Packaging Ordinance," he says. "We will have to make a drastic change to the system if we switch from dry or dry mixed collection. There would need to be organic waste bin collection provided nationwide. We are simply not in a position to change the established system. It would require a huge investment in new sorting systems," he adds.
TiTech's Hüskens points out that it isn't the company's intention to challenge political approaches towards waste management, but to demonstrate what is technical and financially feasible.
"It is politically controversial, yes, but what we want to show you is that it is possible and how much material can be recycled from such dirty waste," he says.
"It's about being open to new ideas - recyclers in the UK, Spain, Italy, and one or two German plastic recyclers, are completely open to these materials [from contaminated mixed waste]. They are willing to give them a try. Of course, the material is dirty and, in the case of plastics,
will need to be washed. But technically it makes sense to handle them."
He adds: "We will never get high-grade paper, but for the mills making tubes and packaging materials, they are fine with this material. The kind of paper we recover in this process is good enough and cheaper."
In Germany, black bag waste is particularly problematic. Most of the recyclable material should have been recovered by other separately collected fractions, yet the trial showed that there is still a great deal of value in this material.
"This is the first time that we have been able to show the amount of material that can be recycled and establish a value for such material that is perfectly good for recycling," explains Hüskens. "This has huge relevance for the rest of Europe. If this material can be recycled, then why do we need so many other separate collections?"
Dean Stiles is a freelance journalist