Vinyl Reborn--Closing the Circle for PVC Waste

Following years of fine tuning, the VinyLoop facility in Ferrara, Italy is now successfully recycling difficult to treat PVC waste and selling a virgin like material to end customers lowering their environmental footprint.

 
Following years of fine tuning, the VinyLoop facility in Ferrara, Italy is now successfully recycling difficultto treat PVC waste and selling a virgin like material to end customers – lowering their environmental footprint. Having perfected its process, the company is now seeking to license it on a commercial basis.

By Ben Messenger

Led by the PVC industry's voluntary commitments to recycling, first in the form of Vinyl2010 and more recently its successor, VinylPlus, over recent years there have been huge strides made in the recycling of PVC wastes in Europe.

According to the organisation's latest report, in 2013 the recycled volumes of PVC wastes saw a significant increase to 444,468 tonnes in, despite adverse economic conditions. Contributing to this achievement was the consolidation of waste streams, as well as the involvement of converters contributing industrial waste in the Recovinyl system.

Recovinyl itself is the organisation that was originally setup by Vinyl210 in order to oversee PVC recycling. More recently VinylPlus charged it with optimising resource efficiency by mediating between recyclers based on a PVC recyclate certification system.

However, VinylPlus also has the ambition that 100,000 tonnes per year of 'difficult to recycle' PVC waste should be recycled using 'innovative technologies'.

One firm that's been doing just that for several years already is Ferrara, Italy based VinyLoop. the company is a partnership between one of Europe's largest PVC producers, Solvay Vinyls and French composite materials manufacturer, Serge Ferarri.

The resulting product produced at the plant is high quality R-PVC which can be used as a direct replacement for virgin materials

The firm originally inaugurated its 10,000 tonne per year facility in Ferrara back in 2002. The plant uses a physical, solvent based technology that is able to recycle difficult to treat, end of life PVC waste, and produce high quality R-PVC (recycled PVC) compounds.

On a recent visit to the plant, Paolo Groppi, general manager VinyLoop explained that in the twelve years since the plant opened, a lot of development work has been done to refine the process. The main challenge, he says, lay in tuning the process to produce a high quality, consistent R-PVC from complex PVC composite materials.

The plant uses a selective dissolution and filtration process to remove contaminants and produce R-PVC. In the early days the engineers refining this process implemented a number of improvements to achieve full control. These included the installation of a pre-treatment stage, fine tuning of the filtration stage and the addition of a new line to complement the one dedicated to cable scraps. The new line enabled the firm to begin treating PVC waste that contained fibre. Finally, a centrifugal decanter was added to purify the solvent/PVC solution.

"What we discovered through time and effort was that if you want to treat difficult scrap you need high technology. If you want to treat very difficult scrap you need very high technology. We spent more or less 10 years to completely manage the process," says Groppi.

How It Works

On a tour of the facility, Francesco Tarantino, Vinyloop's plant manager, explains that the technology works by dissolving PVC waste using a patented solvents that runs in a closed loop. The feedstock, such as PVC insulation jackets from end of life cables, is stored in a series of bunkers. Prior to being dissolved the cable jackets are shredded and passed through a pre-treatment process to recover any remaining copper.

The dissolution of the PVC is carried out in two different dissolvers. Waste composite materials that are free from fibres are processed in the D2 dissolver, while waste with a high fibre content, such as end-of-life tarpaulins, are dissolved in the Texyloop D3 dissolver.

Only the PVC and all of its additives are dissolved in the dissolution units, insoluble contaminants are not. The resulting solution is then passed from the dissolver to a primary filter where solid impurities are separated and removed before the remaining solution is sent to the Centrifugal Decanter for purification.

According to Tarantino the Centrifugal Decanter is the best technology available for removing any remaining contaminants from the solution. Currently still a prototype the system works by applying a large centrifugal force to clarify the solution from residual contaminants and remove part of the mineral fillers used in the original formulation of the PVC compound being processed.

"This decanter is a necessity to sell our PVC in the membrane market. Without it, it would be impossible because the quality of the primary filter is not enough and we have a lot of contamination and if you use it you will have a weak point. The decanter doesn't increase production, it increases quality. It's the best filter for our process," he says.

The contamination removed by both the primary filter, which contains a lot of rubber and high calorific material, as well as that from the Centrigual Decanter that can contain material with a high content of heavy metals, are sent for incineration.

While VinyLoop was originally developed to treat cable scraps, and that still represents the bulk of its feedstock, tarpaulins and fibre containing waste are increasingly important. In 2013, the company concentrated its efforts on improving the efficiency of the treatment of scraps containing fibres, and achieved a significant increase in tarpaulin recycling (802 tonnes, +55% compared to 2012).

These wastes are processed in the Texyloop dissolver, where fibres are separated from the PVC. After being cleaned and stripped they are discharged and marketed for industrial purposes. "It's a very unique material inside of this waste. It's clean – it's not a waste," says Tarantino.

Marketing

The R-PVC produced by the facility is marketed as a 'smart solution' for PVC product manufacturers that want to comply with more sustainable production, resource efficiency and public procurement.

According to VinyLoop it can be processed by extrusion, calendaring and injection moulding for various applications The material is already being used in the production of garden and air hoses and geo-membranes, as well as roofing and flooring products, shoe soles, coated textiles and furniture.

For example, Italian firm FLAG is using the recycled material to make flexible PVC membranes for use in tunnels, buried galleries and other structures, as well as underground car parks.

To boost the environmental credentials of its R-PVC product, the company conducted a Life Cycle Assessment (LCA). The methodology used for the VinyLoop Eco-Footprint Study has been critically reviewed by the German independent testing organisation, DEKRA Industrial, which confirmed its compliance with the ISO standards 14040-44 for Life Cycle Assessment.

The Centrifugal Decanter developed as a prototype by VinyLoop is key to enabling it to market its end product

According to the LCA, membranes made using recycled PVC material can save an average of 40% greenhouse gas emissions, 46% water consumption and 24% energy consumption – based on a product using 75% R-PVC. Garden hoses which have an inner layer made with VinyLoop's recycled material are claimed to save 25% of greenhouse gases emissions, 30% of water consumption and 40% of energy consumption.

While PVC is highly recyclable, the complexity of some of the products in which it is used can significantly' hamper efforts to mechanically recover it

The company uses the results of the study to provide its customers with a visual label which summarises the environmental benefits, and therefore the environmental footprint of their final products, to support effective communication towards final consumers.

Adding Up The Numbers

While the Ferrera plant has enabled VinyLoop to develop, and ultimately prove, the technical feasibility of the process, it is not sited in a commercially suitable location.

"This is the worst place for this kind of plant," explains Tarantino. "It was selected not because there is any synergy, it was selected for political reasons… There was no steam, no electricity, no water, no nitrogen – no utilities."

However, the company says that the technology would be ideally suited to being located at an 'eco park' type development where it could leverage synergies with heat and power suppliers, as well with potential waste PVC feedstock suppliers.

While the facility is located on a site which has been used by the PVC industry for years, it is not ideally suited for VinyLoop's process as it has limited access to utilities and feedstock

The company says that there is also potential for larger facilities to benefit from improved economies of scale when operating at capacities of up to 25,000 tonnes per year. To that end VinyLoop is moving forward with a licensing strategy, whereby it would share its intellectual property and expertise in the development of projects by third parties.

According to Groppi, the company has so far developed a proposal consisting of a preliminary exchange of information with investors that may be interested in its technology, accompanied by a non-disclosure agreement. If it is deemed that the investors are interested in moving forward technical and economic feasibility studies would be conducted.

Conclusions

After over a decade of operation and development, it would seem that VinyLoop has succeeded in creating a method for recovering high quality R-PVC from difficult to recycle materials that would otherwise have gone to landfill or incineration.

The ability to use the resulting product as a direct substitute for virgin materials also widens its appeal for applications where 'green credentials' are important, but where there is no room to sacrifice performance.

However, in order to fulfil the potential of the technology it has developed the company needs to move beyond its home town of Ferrara. With the PVC industry's determination to recycle 100,000 tonnes per year of difficult to recycle material using innovative technologies, it's hard to imagine that the process developed at the Ferrara plant will not spread its wings to more suitable, and profitable climes.

Ben Messenger is managing editor of WMW

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