Progress update (June 2021)
Hazardous goods containers successfully manufactured using 50% recycled content
Funded by the Welsh Government, we have successfully trialled the incorporation of post-consumer recycled (PCR) polymer in containers for the transport of hazardous goods. High quality, recycled, deodorised resins have been used in the manufacture of containers for the highest level of UN certification.
The resins have been trialled at 30% and 50% in 20 litre, stackable jerricans – robust liquid containers – and in compact, five litre containers. The 20 litre containers were put through simulated UN testing to assess performance against containers produced using a virgin polymer. This involved drop tests, air and hydraulic leakage testing, stack tests, and a test to assess environmental stress-crack resistance (ESCR). The five litre containers were also tested to assess ESCR.
All samples passed all tests, demonstrating that adding PCR content to hazardous goods containers, designed for the highest level of UN certification, is feasible at 30% and 50%.
With the upcoming Plastic Packaging Tax and the circular economy now intertwined into most organisations’ goals and targets, these results represent a significant milestone.
The hazardous goods containers are designed for the toughest requirements of the chemical industry, and this has inhibited prior evaluation of recycled plastics. If these high quality PCR resins are approved, they will allow many more companies to use recycled plastics in blends, rather than buying additional equipment and producing multi-layer products to include PCR content.
The next phase of the trial will be to seek UN certification for the 50% PCR containers. Currently, it is thought that this recycled material cannot be used to produce UN containers for the transport of hazardous goods. Regrind from post-production material is accepted, but there are concerns about PCR polymer compatibility and traceability. A known history of what it was previously used for is required, due to the nature of the goods being transported.
Current regulations make it clear that recycled material can be used, provided that it passes the relevant UN packaging tests. There would be no objection if it was proven to perform as effectively as virgin material.
UN testing procedures
The testing procedures that the PCR content must pass are carried out in accordance with accepted published standards such as ISO 16104:2003 and ASTM D4919 – 03(2008).
Different packaging tests are performed depending on the hazardous goods in question. The UN Committee assigned all dangerous goods to one of three ‘Packing Groups’:
- Packing Group 1: High Danger;
- Packing Group 2: Medium Danger; and
- Packing Group 3: Low Danger.
The tests that need to be passed for UN approval include drop, stacking, leakproof, and hydrostatic pressure / vacuum.
Following our simulated UN testing, we now need to formally prove that the PCR resins used in our trial are reliable, with batch-to-batch consistency. Therefore, numerous batch tests are currently underway. The results will be submitted, along with a full UN test report, to the Vehicle Certification Agency for consideration. It is hoped that our 50% PCR hazardous goods containers will pass all tests and be declared ‘UN approved packages’.
The use of PCR in the UN containers is a major step forward in the circular economy; providing manufacturers across Wales, the UK, and beyond with the opportunity to reduce their reliance on virgin polymers.