Getting More Value From Recycled Products

Key Highlights:

• Greenpeace raises concerns about the limitations of mechanical recycling for plastics, highlights that plastic recycling rates have declined to about 5% in 2021, down from 8.7% in 2018.
• The managing director of Gough Engineering, disagrees with Greenpeace, and advocates for investments in processing equipment.
• The article emphasises the importance of investing in specialised sieving and sorting equipment, such as Gough Engineering's Vibrecon vibratory separator.

Greenpeace argues that mechanical recycling, the prevalent method employed in waste management, will fail for plastics due to their difficult sorting nature. However, the European Commission (EC) has mandated that EU member states reduce packaging waste by five percent by 2030, encompassing packaging design and waste management.

Here, Stephen Harding, managing director of Gough Engineering, disagrees, emphasising the need for companies to invest in processing equipment to recover and derive value from recycled products, including plastics masterbatch, as a means to meet the EC's goals. 

Greenpeace's Circular Claims Fall Flat Again report addresses the concerns regarding the inadequacies of current mechanical recycling methods for plastics. The report highlights that plastic recycling rates have declined to about five percent in 2021, down from 8.7 percent in 2018. Greenpeace argues that the sorting of plastics is extremely challenging, making mechanical recycling virtually impossible to achieve.  

The lack of recycling infrastructure is identified as a significant impediment for companies dealing with plastic waste, contributing to the shortcomings of the existing mechanical recycling systems. 

Indeed, today's recycling processing centres are ill-equipped to handle the overwhelming influx of recycling materials, let alone meet the ambitious new targets. According to a report by the Ellen MacArthur Foundation, only 14 percent of the plastic packaging used globally is recycled, while the remaining 86 percent is either incinerated or ends up in landfills or the environment. This stark statistic emphasises the urgent need for better-equipped recycling facilities to effectively process and manage the overwhelming influx of materials to achieve recycling goals. 

For certain recycling, the front-end process requires machinery to granulate product using a predefined set of blades to turn the raw material into smaller particle sizes. These centres face the challenge of transforming inconsistently shaped materials of different types into a uniformly shaped end product that may be separated. This is challenging for several reasons.  

Firstly, irregular shapes can make it difficult to establish consistent manufacturing processes, such as moulding or extrusion, that require standardised input materials. Secondly, the varying shapes affect the efficiency of sorting and separation methods used in recycling facilities, increasing the risk of contamination and reducing the quality of the end product.  

Lastly, achieving uniformity in particle size and material type is crucial for ensuring the integrity and usability of recycled materials in subsequent manufacturing processes, making it essential to invest in specialised equipment and processing techniques to overcome these challenges. Therefore, once granulation is completed, the classification and sorting by particle size using Gough’s product range is fundamental in controlling quality during the next packaging or end-product forming processes. 

But what kind of specialised equipment are we referring to? In short, the solution to these obstacles lies in investing in sieving, and sorting equipment. 

Sorting products  

Sorting products is a crucial aspect of recycling, and industrial sieves serve as invaluable tools across various sectors for classifying and sorting products. Vibratory sieves, for example, are commonly employed to sort raw materials, ensuring the end product achieves a uniform size by passing through different mesh aperture sizes.  

Let’s look at the example of polyethylene terephthalate (PET) bottles. When PET bottles are not properly disposed of or recycled, they can contribute to pollution and waste in landfills or oceans. Recycling PET bottles helps conserve resources, reduce energy consumption, and lower greenhouse gas emissions compared to producing new plastic. 

In recycling, sieves are extensively used to sort granulated PET bottles. Industrial sieves are valuable in recycling PET material because they help separate the different particle sizes, allowing for efficient utilisation of the PET materials for different repurposed value products and their associated review streams.  

Beyond PET bottles, industrial sieves and screens can possess the capability to separate a wide range of materials, including scarce metals in electronics to certain rubber tyre recycling, granulated cable/copper and Waste Electrical and Electronic Equipment (WEEE) waste. Further investment in such equipment can address numerous recycling challenges while reducing or eliminating landfill charges for certain products. 

Illustrating this, let's examine the case of a recycling company in Norfolk, UK, which required a screening operation to classify glass fibres according to quality.  

Gough Engineering, a UK manufacturer of sieving and screening equipment, recommended the Vibrecon GVC5 separator. This customisable system removes fine particles, separates oversize and agglomerates, and facilitates conveying between processes. The system, equipped with two stainless steel grade 304 decks, classified glass fibres at a rate of 750 kg per hour. The top deck eliminates oversized particles, the bottom deck allows easy discharge of fine or undersized particles, and the middle deck ensures the ejection of good material. 

Customised sieving  

By implementing this method, the recycling centre ensures the effective separation of all particles. The Vibrecon circulatory vibratory separator, in addition to recycling glass fibres, finds widespread use in recycling various other materials, including plastics, polymers, chemicals, powders, and ingredients. 

Due to the diverse configurations of sieves in recycling applications, consulting an expert is always recommended. Gough Engineering, with decades of experience in manufacturing customised sieving and screening equipment for industries worldwide, including the recycling sector, stands as a reliable partner. Gough's Vibrecon vibratory screening systems, available in different sizes ranging from 610 millimetres (mm) to 1,630 mm in diameter, cater to a wide array of applications. 

While Greenpeace's Circular Claims Fall Flat Again report rightly highlights the limitations of mechanical recycling in handling plastic waste, sieving and screening equipment offer a solution to these challenges. Recycling companies are well aware of the difficulties associated with separating materials, and should work with a trusted material handling equipment partner to tackle their material separation challenges.  

The new EC mandate places more pressure on recycling centres to increase the effectiveness of their separation. Investing in equipment to improve these processes should be a first step towards meeting the EC’s ambitious targets.