Ensuring supply continuity, quality consistency
One of the issues that always comes up in relation to alternative materials, whether recycled, biobased, or both is that of the continuity of supply. So how does Bywyd ensure this?
“That’s very true, and it is an extremely important question,” said Slijkoord. “Before we start the development of a compound, we are always careful to check the sources needed for a specific compound, but we also check that a sufficient amount is available. Say, we need 100 tonnes – we make sure at least 500 tonnes are available and that the suppliers can guarantee the supply in the future. And we don’t rely on just one supplier.”
Regarding the consistency of the quality, Bywyd sets up the quality control specifications for every step in the value chain, from the incoming feedstock to the final product, and checks that these are complied with at each step. The result is a technical data sheet and a material safety data sheet.
“What we think is also important -and surprisingly it is not yet common practice – is to detect a scatter in the material’s properties as well. For example, if referring to the strength of a material, we show the minimum strength and the maximum strength, which tells designers using our material that they can rely on the minimum strength and design the product accordingly. They can be sure that, in any case, the material will not break in the application. So, the scatter in the material properties is very important – and the better we control the quality in the value chain, the less scatter occurs in the final product, the better the product’s consistency becomes.”
This applies to the right raw material selection and purification step at the very beginning - any impurities in the input material influences the property scatter in the final product, as well, he added.
Hospital waste – a business case
The first actual project demonstrating Bywyd’s approach involved the creation of a chair based on polypropylene derived from nonwoven blue wrap hospital waste. The chair, called the Blue Finn, is manufactured by Vepa, one of the leading furniture manufacturers in the Netherlands, and also active in the United Kingdom, Belgium and Germany.
The blue wrap is supplied by PreZero, with whom Bywyd has partnered. PreZero collects the blue wrap from a number of hospitals. Blue wrap is a nonwoven material used for wrapping surgical instruments for sterilization. It is generated and used in only a few areas, such as surgical rooms. It is a clean, uncontaminated waste stream that can be collected for recycling.
“Per year, each hospital in the Netherlands generates about 20 tonnes of blue wrap - a huge amount,” said Jan Willem Slijkoord. “So, we thought of a way to reuse it.”
The first step, he said, is to sort the waste, to ensure no paper, clothing, towels or gloves have accidentally found their way into the waste. The company works with a sorter for this step.
“After sorting, the blue wrap is baled into large bales, and then shredded into smaller foil pieces. These pieces are then melted and regranulated. In the next step, a compounder adds a number of additives to transform the very brittle bluewrap polypropylene into an impact modified PP which can be processed on an injection moulding machine,” explained Slijkoord. “The original blue wrap material is an extremely high flow material, suitable for producing the fibre used to make the nonwoven polypropylene and, as I said, is a very brittle material. However, to produce a chair, the flow needed to be decreased by over 70% and the impact resistance improved by a factor of 2.5, which is quite significant.”
The resin demonstrated the required properties and successfully withstood Vepa’s vibration test, which meant it could be used for the application. It was delivered to the injection moulder, who moulded the parts, after which these were delivered to the end customer – Vepa – who assembled the parts on the frame. The chair is available as a bar stool, a semi-high bar stool and a regular chair. The components are designed for disassembly and for reuse them after use.
This first project has been successfully completed and Bywyd is now testing a product for another customer active in the global flooring industry.
“This customer produces cast resin floors. They are currently testing whether it is possible to use waste - not from hospitals, but from another source – to produce their floors. And we are also in contact with several global producers of, amongst others, household products. We are seeing quite a lot of interest in our vision,” said De Bruijn.
A vision, added Slijkoord, that strives to give value to waste by creating a valuable material that is sustainable – ‘no greenwashing, but a fair material that is backed up by a solid story and solid arguments, that resonate in the market’.