Click Here to go to the Recycling Archives

Industry Hears Impressive Results Confirm Viability of Recycled Glass

Key decision makers have heard how the market for recycled glass products is growing, following a series of successful trials.

The results were revealed at the annual GlassAction meeting, held at Tankersley Manor, Barnsley, which was attended by more than 100 top industry professionals from all over the country.

Andy Dawe, Materials Section Manager (Glass) for WRAP (the Waste & Resources Action Programme), reported on a series of industrial-scale trials, funded by the organisation. These projects covered sectors including brick and tile manufacture, filtration, grit blasting, sports turf and cementitious products.

He said the tests had demonstrated the commercial viability and at least comparable performance of recycled glass, compared to traditional materials, such as sand, which were often not renewable.

Mr Dawe said:
'These trials have highlighted the many different benefits recycled glass can offer British industry. By demonstrating the advantages of using it, we have provided a good business case, which UK companies will find hard to ignore.'

Among details of the tests, delegates heard how trials with members of the Shipbuilders & Shiprepairers Association had shown grit made from recycled glass achieved a comparable profile to copper slag when preparing surfaces for paint and coatings.

In trials undertaken by consultancy Aqua Enviro, filtration media made from 100 per cent recycled glass had been proved to be capable of removing suspended solids from effluent more effectively than traditional materials, provided the right size of glass was used. It also delivered more efficient backwash performance and showed no marked tendency to clog up or blind.

Delegates also heard how trials at Tamworth-based highway maintenance product manufacturer Instarmac had shown the material to be a suitable alternative to silica sand in mortar and tile adhesive products.

Mr Dawe said: 'We've also seen very encouraging results from the brick industry, which showed that adding recycled glass as a fluxing agent during manufacture could increase productivity, reduce firing times and, as a result, lower CO2 and HF emissions. With the dramatic increases in energy prices recently, we expect take up of recycled glass to increase in this sector, as these benefits will help to keep costs down, as well as offering environmental advantages.'

Research undertaken with the Sports Turf Research Institute has shown processed sand using recycled glass was suitable for golf course maintenance and conformed to United States Golf Association specifications for root zone construction.

In addition, delegates heard from Gary Bell, Managing Director of Fife-based concrete block manufacturer Brand & Rae. He explained how trials at his company had confirmed crushed recycled glass was a suitable replacement for primary aggregates. In certain cases, it also showed improvements in strength, resistance to frost and extreme weather conditions, and reduced drying shrinkage.

The manufacturer has now begun offering a concrete block containing 30 per cent recycled glass as part of its standard product range.

Mr Bell said: 'This application is a highly effective way of reusing stocks of mixed colour glass, which the container industry cannot accommodate. We're committed to producing and marketing concrete blocks containing recycled glass and believe more material needs to be made available for this application. We could potentially use as much as 65,000 tonnes per annum.'

Delegates heard how WRAP was encouraging UK firms to consider bulk importing of wine, to reduce the quantity of glass coming into the country. Bulk shipment is a growing trend and currently accounts for 20 per cent of imports.

Mr Dawe said: 'With the UK's wine consumption growing, we'll be producing in the region of 1,100,000 tonnes of green glass waste every year by 2008, but only 350,000 tonnes are currently absorbed by bottle manufacturers. Bulk importing can achieve great results because not only does it reduce the number of bottles coming in, it creates another avenue for recycled green glass, and offers cost savings for the wine trade.'

Chairing the meeting, David Workman, Director General of British Glass, said:
'We're delighted at the success of this year's event. The extensive work that WRAP is undertaking to promote the glass industry will lead to big improvements in recycling rates in the UK and we now need to strengthen the supply chain to accommodate future growth in demand.

'The industry is united behind this aim and I'm confident GlassAction Day will prove a highly effective way of bringing together all the interested parties to discuss the barriers and issues, as it will lead to positive actions.'

The GlassAction forum is supported and co-ordinated by British Glass and WRAP, to develop closer working relationships between existing, new and potential end markets, collectors and reprocessors.

Its meetings allow delegates to learn about the latest developments, express their views, network and contribute to future strategies.

Other speakers at the event included Ian Harrison of Brand & Rae, Shamshad Ali of Instarmac, Nick Kirk and Dave Dalton of research consultancy Glass Technology Services and Peter Mainprize of WRAP.

Any companies interested in setting up a trial or learning more about recycled glass applications should contact Andy Dawe at WRAP on 0808 100 2040.

Web: http://www.wrap.org.uk

Recovinyl Aids PVC-U Recycling at Stoke on Trent

More than 500 'first generation' PVC-U frames removed from social housing were successfully recycled as part of a major refurbishment project at Stoke-on-Trent.

Labour and funding provided by the BPF-backed Recovinyl Scheme helped to fulfil the project's stringent recycling specification. The scheme offers practical and financial incentives to UK window installation companies who participate in recycling.

The project is part of on-going refurbishment by the Local Authority's manufacturing and installation arm, City Windows, to install modern PVC-U windows meeting current thermal, security and fire egress standards.

The removed frames were returned by City Windows to a secure site provided by the council where they were manually deconstructed into 'L' shapes using special 110V powered corner-cutters, developed with funding from the BPF and EPPA.

Glass, galvanised steel reinforcing, rubber and PVC-U were separated in separate skips and cages to be sent for recycling. All the flat glass waste was sent to Viridor Glass Recycling, with waste PVC-U processed by specialists PVC Group. Frames were dismantled with local labour supplied by the council and PVC Group, with assistance from profile supplier Aluplast's Sales Manager, Dair Hendry.

In total, around four tonnes of PVC-U and 5.5 tonnes of glass, which filled a nine cubic-yard skip supplied by Viridor, were recycled.

Several valuable lessons were learned from the project, says its co-ordinator, independent plastics consultant Steve Weston. ‘By cutting the windows at opposing corners into 'L' shapes, they were much easier to handle than full frames enabling the team to work and store them more efficiently.

‘Keeping glass waste clean is vital to maintain its high value. The skip contents were protected from contamination by other waste with a tarpaulin and because it was a secure site, a lockable lid was not necessary to comply with regulations.
Viridor praised the cleanliness of the glass waste, saying 'this is exactly how we want it', which meant it could all be re-used for fibreglass insulation.’

Commitment from all was essential to the recycling success, concludes Steve. ‘City Windows' insistence that these frames had to be recycled rather than landfilled was a key driver of this project. It also demonstrates what can be done if there are the resources and the will to adopt new working practices.’

As a 'pump-priming' device to remove barriers to recycling, Recovinyl subsidises installers for the extra costs of dismantling, sorting and transporting separated PVC waste. It also provides access to accredited recyclers.

The Recovinyl scheme is now starting to make a real impact on the recycling of more post-construction PVC waste with over 50 UK waste collectors and 17 accredited PVC recycling companies now signed up to scheme.

Free to join, the scheme also covers ancillary PVC products such as roofline products, cladding, shutters and blinds. By providing the subsidy streams and technical support to help recycling projects happen, Recovinyl aims to ensure a steady supply of post-consumer PVC waste for recycling on an industrial scale, making it a viable and economic reality.

Dr Mercia Gick, the BPF's Senior Advisor on Industrial Issues, describes the Stoke project as a model of how the PVC industry can assist local authorities in recycling window frames.

‘The Recovinyl incentives help projects like this, putting the infrastructure in place for when post-consumer PVC-U recycling will have to be the norm. With legislative changes making landfill disposal becoming an increasingly unviable option under the Government's environmental sustainable objectives, the industry will be forced down a 'greener' route and recycling is the obvious solution,’ she adds.

As well as promoting greater recycling by installers, Recovinyl is also calling on specifiers to insist on post-consumer PVC-U recycling clauses in social housing refurbishment contracts - currently one of the biggest sources of old single-glazed PVC-U frames.

Further information on the Recovinyl scheme is available at http://www.recovinyl.com or from an information helpline Tel: 0870 240 2416 Fax: 0870 240 2417. Alternatively contact Axion Recycling http://www.axionrecycling.com or Tel: 0161 426 7731

Separation of Contamination from Ground PVC Window Material

Clean PVC regrind from recycling of PVC window profiles is a valuable raw material, that can be used again for the production of PVC windows. But contamination such as by rubber from seals, polyamide, plasticised PVC, etc are problematic. Such contamination can influence the possibilities of using PVC recyclate or even make the use of recyclate impossible. The rubber seals are therefore normally separated manually before shredding. This process is laborious however, only allows a low rate of throughput and is therefore not suitable for economic recycling of used windows.

  
(L-R) Input fraction, (1) PVC regrind with rubber; (3) Reject, from PVC regrind separated rubber; (4)Clean PVC regrind for production of new window profiles

The separation process used by hamos GmbH in Penzberg works however entirely automatically, i.e. without manual pre-sorting. The PVC window profiles are firstly shredded into regrind, from which dust is then removed (Illustration 1). The material is then largely freed of rubber and other contaminants by an EKS type of electrostatic separation equipment (Illustration 2). Use is made here of the different electrostatic charge of rigid PVC compared with rubber (Illustration 3) and other substances. The PVC has purity of approx. 99.5% after this stage of separation.

The subsequent type SEA optoelectric colour sorting equipment separates the rubber and possible colour contamination from the material, so that the PVC material (Illustration 4) is distinguished by now having purity of more than 99.995%.

EKS electrostatic separation equipment

The combination of the hamos EKS and SEA has proved itself many times worldwide. The process guarantees high throughput and optimum product purity, whereby other contamination that arises in window recycling, such as metals, wood, glass and minerals, are also separated out.

hamos GmbH will show this process at the fensterbau/frontale 2006 fair. fensterbau/frontale 2006, 22-25.3.2006, Nuremberg, Hall 3, Stand 405.

Tel: +49 (0) 8856 9261 0
Email: hamos@hamos.com
Web: http://www.hamos.com

Recycled Glass Delivers Clear Benefits for Water Treatment

Results of commercial-scale trials into the use of recycled glass as a medium for filtration of industrial and domestic wastewater have indicated it could cut the costs of treatment, as well as being kinder to the environment.

Wakefield-based water treatment specialists Aqua Enviro are conducting trials of recycled glass filtration medium (RGFM) with a cross-section of end-users: Croda Chemicals Europe, at its plant in Rawcliffe Bridge, Goole; frozen fruit and vegetable processor JE Hartley, in Thorganby, York;

Yorkshire Water, at its sewage treatment plant in Malton, North Yorkshire; and kitchen roll and tissue manufacturer Georgia Pacific UK, at Stubbins Mill, Ramsbottom, Bury.

Interim results of the trials, which have been funded by WRAP (the Waste & Resources Action Programme), have shown that using recycled glass as a filtration medium could improve the quality of effluent, compared to traditional sand. It could also help water companies and industry to meet tough new environmental targets and avoid fines, without incurring extra costs.

The Environment Agency regulates the amount of suspended solids that are permissible in water discharged into watercourses. Organisations exceeding their limits may face heavy penalties.

Reduction of suspended solids is important, as they have a negative effect on the environment by de-oxygenating water, with a consequent detrimental impact on fish habitat. Excessive growth of blanket weed brought about by suspended solids can also affect river flow as silt and other particles build up when they are caught in the weed.

Mark Lowe, consultant, Aqua Enviro, said: "The results of trials of the RGFM trials have been positive and encouraging. Tests have shown the medium is more effective than sand at removing suspended solids in effluent and delivers better performance in backwashing. As a result, less frequent backwashing is required, leading to cost savings.

'Unlike sand, the recycled glass has shown no tendency to clog up, or 'blind', when faced with high loadings of suspended material, leading to fewer blockages.'
RGFM is set to reduce suspended solids in water discharged by Croda Chemicals Europe into watercourses by up to 80 per cent, from 250mg/l to 50mg/l. This will help Croda to meet the standards of the Integrated Pollution Prevention and Control accreditation. The material has coped excellently with major peaks in solids loading. It could also help Croda to cut operating costs, through reduced cleaning and maintenance bills and lower capital outlay in the future, as the company will need a smaller membrane system to allow water reuse within the plant.

Tissue, pulp, paper and packaging manufacturer Georgia Pacific UK has used RGFM to treat effluent water destined for reuse at its plant or discharge into the sewage system. RGFM has reduced levels of suspended solids, which can be as high as 280mg/l, by 80 per cent.

The trial has also shown that other significant benefits can be achieved by recycling the cleaned water back into the mill. These include the fact that the effluent, once removed of other impurities, is still hot and would not require re-heating.

At JE Hartley's plant, which processes and distributes vegetables, RGFM has also outperformed sand as a filtration medium. RGFM removed 80 per cent of suspended solids from effluent compared to 32 per cent for sand. Hartley's is now considering upgrading its filtration process to incorporate RGFM in the future.
In addition, Yorkshire Water has trialled RGFM at its sewage treatment plant in Brawby, Malton, which serves 10,000 households in the town. RGFM has proved to be more effective than sand and it has helped the utility to reduce suspended solids in the effluent, which is discharged into the River Derwent, by 70 per cent.
Performance on backwashing also matched or bettered that of sand.

Mark Lowe said: 'If the interim findings are confirmed in the final report, they will have implications for a wide range of industrial sectors treating wastewater including heavy engineering, car manufacture, food and beverage factories and paper and pulp mills. They could also highlight RGFM's potential as a filtration medium for drinking water and in aquaculture applications, including fish farming, as well as for water used in swimming pools and spas.

'The results will be of particular interest to manufacturers of filtration equipment and media, as well as managers responsible for effluent quality requiring a more consistent and sustainable solution to their treatment problems.'

Bronnie Allen, materials development manager at WRAP, said: 'We're delighted with progress to date. So far, trials indicate RGFM, which is manufactured to BSI PAS 102 specifications, is viable commercially and offers economic and performance benefits compared to traditional filtration materials. It is also a way for companies to demonstrate commitment to the environment.'

Companies interested in learning more about recycled glass applications should contact Bronnie Allen at WRAP on 0808 100 2040.

Web: http://www.wrap.org.uk

US Army Salutes UK Recycled Glass Initiative

The US Army has completed a major manoeuvre by switching to environmentally friendly grit blast media, made from recycled glass, at its Field Support Battalion base near Southampton.

Glass grit, sourced from reprocessor Krysteline, is being used to refurbish military equipment - including land vehicles, generators and watercraft - at the site in Hythe after the army switched from using traditional copper slag.

Grit blasting involves abrasive particles being powered onto a surface using high pressure air and is often the fastest and most thorough means of cleaning, descaling, deburring and removing oxides or other surface contaminants. The process is widely used in many industries, including aerospace, construction and transport.

In addition to helping environmental sustainability, recycled glass grit's main benefits are that it is non-toxic, inert and does not cause respiratory or environmental problems. It contains negligible levels of chlorides and salts that can corrode clean surfaces and its residue being classed as a nuisance dust, rather than hazardous waste, means disposal costs can be lower.

The introduction of US HAZMAT regulations, governing the use of hazardous materials, was another factor in the unit reconsidering its choice of abrasive.

Colin Buchanan, Paint Supervisor and HAZMAT Officer at the US Army Field Battalion, said:
'The unit has been particularly impressed that glass grit creates significantly less dust during the blasting process, which had been a problem for us in the past, and any it does generate is easily controlled.

'Another benefit we have identified is that, in addition to complying with HAZMAT regulations, the glass grit can be disposed of in a number of ways, without presenting an environmental hazard. It has also proved more cost-effective than many of the alternative materials we investigated.'

The eleven-acre army site offers facilities tailored for the maintenance, overhaul and storage of forward deployed combat equipment. Many of the vehicles have suffered significant war damage, making it necessary to strip back all paint on the chassis and bodywork, to determine what metal damage has been caused.

Once stripped to bare metal, the parts are blasted with TruGrit recycled glass blast media in preparation for repairs and re-painting, in the appropriate camouflage colours, ready for release back into service.

Mr Buchanan said:
'By sharing the results of the tests here, we hope to encourage other army sites across the world to consider switching to glass grit. The benefits it offers in terms of cleanliness, ease of control, cost effectiveness and environmental performance all add up to make it an ideal product for blasting.'

At Hythe, two types of equipment are used during the blasting process, a standard shot blast system and a portable, lightweight blasting gun, which enables paint to be stripped layer-by-layer. Currently the unit uses four tonnes of medium grade (0.75 - 1.5mm) glass grit every week, at a pressure of 200 PSI.

Bronnie Allen, Materials Development Manager (Glass) at WRAP, said:
'Recycled glass grit has been proved in the USA to achieve a suitable surface profile on steel for paints and coatings. It has been used for cleaning many different surfaces very successfully in this country but, up to now, usually in environmentally sensitive locations, such as near watercourses.

'We hope that trials such as this will prove the commercial and operational benefits of glass grit and encourage specifiers and contractors to use it more widely.

'We're delighted that the US Army has made the decision to switch to the new medium and we hope others will sit up and take note of the benefits it has to offer.'

Recycled glass is available manufactured to BSI PAS 102 specifications, meaning buyers can procure material confident it is fit for use.

Any companies interested in setting up a trial or learning more about recycled glass grit applications should contact Bronnie Allen at WRAP on 0808 100 2040.

Web: http://www.wrap.org.uk

GO TO RECYCLING ARCHIVE PAGE

RETURN TO HOME PAGE