Sustainability is a one of the key demands of customers and regulators of the polyurethane industry in Europe. It was one of the themes at this year’s Europur meeting in Vienna on June 11-13
Sustainability is becoming more important but what do people mean by sustainability and what should the European flexible foam manufacturers be doing to ensure that their products and business approach are sustainable in a rapidly changing and unclear regulatory frame work?
The European Waste legislation framework looks fairly straightforward. There are five main pieces of general European legislation covering the area: The waste framework directive and the waste shipment regulation which give the overall aims. Under these there are the Waste Incineration Directive, the Landfill Directive and the Industrial Emissions Directive. There are also a number of regulations covering specific waste streams such as vehicles, waste electronic and electrical equipment.
As far as the flexible and rigid polyurethane foam sectors are concerned, the landfill directive will have the most important changes on the waste landscape over the coming years.
By 2014 this directive sees a reduction in biodegradable waste to landfill to 35% of the 1995 level. The expectation is that the update to the 2013 landfill directive will start to phase out landfill as a destination for high energy waste. This would make it hard to put end of life (EOL) mattresses and furniture into landfill if there were other recycling options.
European Union member states have started banning landfill of high energy waste in their national legislation. European Union members Austria, Belgium, Denmark, Germany, and Sweden have imposed such a ban. Non-members, Norway and Switzerland, also have bans in place and Finland, which is a member, is implementing a ban with a transition period until 2016.
The European Union has a hierarchy of preferred options for dealing with waste.
- Prevention:
- Preparation for re-use: operations which allow products or their components to be reused in the same role
- Recycling: Any reprocessing operation allowing waste to be reused for the original or other purpose. This excludes energy recovery or reprocessing into fuel
- Recovery: Any operation that allows waste to substitute for another material and includes energy recovery and conversion into fuel
- Disposal: all other methods of dealing with waste.
This seems clear but there is no consistent definition of recycling in practise. Another problem is that of extended producer responsibility.
Extended producer responsibility is defined by each state, and is based on the idea that the polluter pays for the waste. This is usually restricted to the current owner or original purchaser of the polyurethane mattress or sofa but member states could decide that the cost should be carried by the producers or distributors of the furniture.
Recticel’s Ward DuPont carried out research into European waste recycling for polyurethanes as part of the Europur product stewardship working group.
Some of the industry’s suggestions around waste prevention included trying to bring mattress thicknesses into line with objective technical requirements, and improving the durability of mattresses so that there would be fewer to mattresses to recycle and the ones that are made should use the maximum amount of recycled materials.
DuPont’s paper notes that while there is very little mattress re-use/renovation, there is a $1bn market with 50 active mattress renovators.
Recycling could see more polyurethane mattresses available to be turned into chips and added to rebounded foam for floor covering. This market is currently in balance with post-production scrap and cannot absorb additional volumes, said the Europur report.
Waste to energy is “mature technology, technically and environmentally proven to be safe” said the report. There are 400 plants operating in most member states. These convert around 80 MT/year waste foam into 35GWh electrical power and 65 GWh heat. In 2012 Eurostat figures show that the EU generated 3295234 GWh electrical power from all sources.
This is an enticing route for the polyurethane industry to push. There is no need to prepare mattresses before incineration, the process can handle all end of life mattress materials except steel. Finally, on the plus side, the process is “a net saver of greenhouse gas emissions because the CO2 generated by the process is lower than the CO2 produced by the normal generation mix in the EU to generate the same amount of electricity, according to the report.
On the negative side of the equation, political acceptance varies from county to country.
Other sustainability options
Chemical recovery is attractive but has limitations in flexible foam, the Europur report suggests. To be effective, chemical recovery methods need a homogeneous input stream to deliver a useable recyclate. Acidolyisis is commercially available and converts polyurethane into a secondary polyol that can be re used. But foam mattresses made with old formulations may contain additives and blowing agents which are grey or blacklisted. It would need extra processing to remove these. The application of acidolysis in flexible foam is also unfavourable in terms of the material balance.
The report said that it takes one tonne of prime polyol to recover one tonne of end of life foam. “The resulting secondary polyol must be diluted with prime polyol by a factor of four to be fit for prime foam production.” However, this discusses flexible foam only and the report adds that production from single market foaming plants could deliver a good homogenous input streams but these are limited in number.
A third route could be gasification which converts shredder residue into synthesis gas – a mixture of hydrogen, methane and carbon monoxide. The process has been around for a while and has been given a new twist by Ecoloop. This company is part of Xella a building materials group from Germany. The Ecoloop process uses air as the main reactant and lime as a catalyst and scavenger for potential pollutants such as halogens and dioxins. Ecoloop has a 32MW pilot plant at Ebingerode, Hannover, Germany which went into operation in the last quarter of 2012.
Ecoloop claims the plant has a thermal efficiency of >80%, an emission-free process, costs below fossil fuels and a low capital intensity <EUR 1m/MW generated. Synthesis gas is a versatile chemical feedstock, and can be burnt as a fuel replacing natural gas or it can be used as a fuel to generate electricity. The process can handle end of life materials apart from metal and wood. There is a minimal preparation step of cutting the feed into 30x30 cm dimensions.
A fourth option would be composting a process developed by EWS, Marquette and Michigan it is ready for worldwide licensing. This currently takes 40 days to convert PU foam, latex and fibres into high quality humus. However the cycle could be reduced to 20 days at minor extra cost, the report said.
The process depends on multiple generations of micro-organisms. Greenhouse gasses and excess process water are treated on site and excluding humus sales, the cost is EUR 21/tonne.
