The UK glass industry is increasingly concerned about the decline in furnace-ready cullet available to UK glass container manufacturers. In 2007, there was a decrease of over 56,000 tonnes going back …
The UK glass industry is increasingly concerned about the decline in furnace-ready cullet available to UK glass container manufacturers. In 2007, there was a decrease of over 56,000 tonnes going back into closed loop recycling. Despite production increasing by over 46,000 tonnes over the same period in 2006, the actual amount returned to remelt was 696,000 tonnes. Rebecca Cocking, recycling manager at British Glass, said, “Had the 56,000 tonnes of cullet (recycled glass) gone back into container manufacture (remelt) this could have resulted in a saving of an additional 13,500 tonnes CO2 as well as reducing the amount of raw materials required and energy usage”. Despite the decrease in the amount of cullet available to the container industry, the total amount of glass extracted for recycling by UK processors has increased significantly. The official figures published by the Department of Environment, Food and Rural Affairs shows that in 2007, total glass recycling reached 1.44 million tonnes. This equates to a UK recycling rate of 55% based on a waste stream figure of 2.65 million tonnes. In comparison to 2006 this is an overall increase of around 110,000 tonnes. The exporting of cullet to Member States for use in container manufacture also increased in 2007, from 230,000 to 270,000 tonnes. “The reason behind this decrease in container-ready cullet, “said Rebecca, “is due to the way in which the UK collects materials from the Household Waste Stream for recycling. More and more Local Authorities and Waste Management Companies are relying heavily on what are known as commingled collections. This is where all materials – glass, paper, plastic, metals and, in some instances, textiles – are collected together and sent to Material Recovery Facilities for sorting because they believe that this “one stop“ solution is the most economical collection method”. “The result is that the cullet is not only being colour mixed, it is also being compacted and mixed with the other materials, possibly making the end product less suitable for new containers. The cullet from such activities is not only potentially unsuitable for container manufacture but could also affect fiber applications. The result is it is only suitable for low grade applications such as aggregate from which little or no carbon benefit is derived”. Part of the driver for this change in collection method is the UK requirement to meet the Landfill Directive, and the UK Government setting recycling targets on Local Authorities that are not material-specific but focused solely on weight. “Although British Glass understands why these collection decisions are made,” continued Rebecca, “we are concerned that the current practices may potentially be inappropriate in the long term and that, as local authorities can be tied in to long-term contracts, we may be implanting practices that may need to changed in the future. The worry is that unless all parties in the supply chain address this issue urgently, the environmental benefit of closed-loop recycling cannot be realised”. While glass processors over the years have introduced technology to assist with colour sorting, the technology is not currently available to pull good quality out of the waste stream once it has been compacted to a high degree. There is a possibility of introducing technology at the front end of a materials recovery facility but again the success of such technology will be dependent on the size of the material being collected. With any additional activity in processing costs rise. The concern is that as more and more processing is required then the final cost of the end product could increase, resulting in the material being uneconomical when compared with the raw material alternative. “The evidence proves that closed loop recycling of glass delivers the greatest environmental benefit in terms of reducing raw material use, energy consumption and emissions,” commented Rebecca, “and new containers can be produced time and again without any loss of quality or purity. The UK Glass Industry is anxious that this growing trend will radically impact on other current and future legislative drivers”. In 2004 a report was commissioned undertaking a Life Cycle Assessment (LCA) examining the environmental benefits of different end uses for recycled glass. Recycling glass for containers produced in the UK saves 314 Kg of CO2 per tonne of cullet recycled. Fiberglass saves 275 Kg of CO2 per tonne, bricks save 66 Kg, shot blast 19 Kg, while use of recycled glass for aggregates results in an increase of 2Kg of CO2 per tonne of cullet recycled. Rebecca concluded, “Despite continuing lobbying on this issue the trend is growing and it looks unlikely to change in the near future unless legislative intervention occurs and coordinated effort takes place. Sustainability is a long term activity not just a “here and now“”.