Trifol turns plastic waste into waxes

Materials World magazine
,
27 Sep 2019

Plastics destined for the waste heap are being turned into new products that can be used as a drop-in material.

Reclaimed polyolefin soft plastics are being turned into waxes as a substitute for materials that would otherwise be crude oil-derived.

Material processing company, Trifol, Portaloise, Ireland, uses soft film products, for example plastic bags, wrapping and packaging to process into the waxes. ‘Currently the majority of waste plastic is sent to landfill or incinerated. Polyolefin soft plastics, the company’s targeted waste plastics stream, are the most notoriously difficult plastics to recycle,’ Trifol said.

Material recovery

According to Plastics Europe 2018, of the 27 million tonnes (Mt) of consumer waste plastic collected in the EU in 2016, only 31% was recycled, while 42% was incinerated and 27% went to landfill, resulting in 18.7Mt of plastic waste released into the environment in one year alone. Trifol is able to use some of that product that may go to landfill. For every tonne of material produced, Trifol takes 1.5 tonnes (t) of plastic waste from landfill.

Trifol Chief Technologist, Fergal Coleman, told Materials World the films are recovered by a waste management operator in a materials recovery facility where they are picked, shredded and washed.

The company processes film that comes in as a flake with less than 5% moisture content. ‘Typically, the plastic in this stream is more than 95% low density polyethylene. Whilst rigid polyolefin plastics, for example plastic milk bottles, are also suitable for conversion to waxes, we do not target this stream as it has higher value,’ Coleman said.

Pyrolysis

A patented pyrolysis process is used to treat the polyolefins. ‘When heated to more than 400°C, the molecular bonds in polyolefin plastics begin to break, releasing shorter chain molecules which evaporate from the pyrolysis reactor as they are formed,’ Coleman said. ‘Using distillation, these products are then separated downstream according to boiling point, into a number of products including naphtha, a gasoline-like fraction, gas oil, similar to diesel and kerosene, and wax.This wax is a drop-in replacement for crude oil-derived slack wax in several applications. Use as a feedstock for synthetic lubricant production is one of the biggest potential applications, by volume. Conversion to a synthetic lubricant base oil involves a catalytic dewaxing process and would be carried out in partnership with a lubricants partner.’

The material is sold to wax blenders where it can be formulated into various slack wax products or refined for higher applications. Trifol stated that the new development is chemically identical to virgin wax and can be used in any application, from printer ink to waxed fruit.

The company claims their process has zero emissions and contributes about a 30% reduction in greenhouse gases.

Commercialisation

The company has been able to scale up their operations from the laboratory to a commercial factory. At the launch of the new factory in July 2019, Ireland Minister for Justice and Equality, Charlie Flanagan, said plastic waste was a topical and emotive issue. Flanagan said he was delighted an Irish company was taking a lead in reclaiming such materials and turning them into a commercial opportunity.

‘The company has chosen Portlaoise as a central location to convert plastic waste into waxes. Most significantly Portlaoise will be a reference site to showcase this Irish technology, with a view to exporting it,’ he said.

The company’s production capacity is currently at 10t per day and it hopes to scale this to 30t per day in 2020. They aim to be operating 24/7 by the end of this year. The company has ambitions to open several sites across Ireland and further into Europe and the USA.

Four patents for the technology were published by the European Patent Office in December 2018, while others were filed in the USA. The team has worked with Queens University Belfast since the company’s inception in 2014. At the university, a pilot plant was built and then operated through to 2016 to develop a proof of concept. The University of Limerick has since become involved for product testing.