Harnessing technology developed by the University of Dundee, Greenward Environmental Technology has been working with Llanelli-based Metal Reduction Processors to test a catalyst formula based on an alloy of palladium and zinc at the back end of the low-temperature pyrolysis process (polymer cracking or breakdown at approximately 5008C). The company has an agreement to obtain licences from the university for the manufacture of catalyst materials and to operate exclusively in the field of plastics recycling.
Emissions from the polymer-cracking process include hydrocarbons, chlorinated hydrocarbons and acid gases which must be converted into carbon dioxide and water prior to release to the environment. The presence of chlorine has traditionally presented a significant challenge to other polymer-cracking projects but this latest patented catalyst formula is claimed to work even under PVC-rich conditions.
Managing director Dr David Hutson (pictured) and technical advisor Dr Jim Thomson are spearheading Greenwards development. According to Hutson the technology could realistically achieve an efficiency of 99.99% or even 99.999%, is scaleable and bespoke facilities could be matched to geographical and capacity needs.
Plastics would be treated close to the source rather than incur costs in transporting the waste to the nearest landfill site or materials recycling facility. We feel we will be able to keep the costs down. Part of the intellectual property is how the catalyst is manufactured we feel our process uses the metal to the maximum and so uses less of it.
The catalyst has been tested within the University of Dundee and has also been the focus of small-scale pilot testing at Metal Reduction Processors. However, the project is still in the embryonic stage and further funding is required to validate the process and to determine, for example, the life time of the catalyst.
Hutson said he was confident that an application to the Scottish Executive for £50,000 would be approved in the near future and that Greenward would be incorporated some time this summer. Additional funding of just over £50,000 would be sought for the second year. Hutson underlined that business support was also important to the future of the project given an investment target of £200,000 in the first two years.
If current funding goals are realised, the aim is to open a facility in Scotland to manufacture the catalysts by late summer next year.
Hutson points to materials recycling facilities as the target end-users of this technology. At the same time, he puts the UK market for recycling discarded household plastics into oil at £250m per year of which an estimated 5% or £12.5m a year is accessible to Greenward. As well as the domestic refuse stream, he also pointed to the agricultural sector and to obsolete electrical and electronic equipment as potential sources of feed material. Other sources of plastic waste arise in the commercial, construction and demolition industries and sales opportunities exist in these sectors for bespoke plastics recycling based on pyrolysis and catalyst technology, he emphasised.
The oil product resulting from the process is of quite a high quality without much refining, he added. A potential outlet would be re-use as a petrochemical feedstock to produce more plastics or other commodities. It could also be used as a domestic heating fuel or for diesel applications although, in these cases, further refining would be required. u