Environment

Dyeing without water

11/02/2019

DyeCoo, based in Weesp near Amsterdam, is a leader in water-free and chemical-free textile dyeing. The company’s technology uses carbon dioxide instead of water in the dyeing process, effectively freeing textile dyeing companies from reliance on water resources that might be limited and environmentally sensitive. DyeCoo (literally: dyeing with CO2) was formed in 2008 in a partnership between CO2 technology company FeyeCon, Delft University of Technology and textile printing company Stork Prints. The sustainability benefits of DyeCoo’s technology are gaining increasing recognition with, most recently listing as a finalist for the 2019 Circular Economy Awards, an initiative of the World Economic Forum. DyeCoo’s Femke Zijlstra answered questions on the CO2 dyeing technology and how it is being taken up by the industry.

Could you give a short, clear explanation of your waterless dyeing process, and the main sustainability advantages it offers?

Femke Zijlstra: The textile industry uses on average about 100-150 litres of water to process 1 kilogramme of textile material. Some 28 billion kilos of textiles are dyed annually. DyeCoo uses a patented and industrially-proven dyeing technology based on carbon dioxide instead of water. So how does it work? The technology uses (reclaimed) CO2 as the dyeing medium in a closed-loop process. When heated and pressurised, CO2 becomes supercritical, a phase between a liquid and a gas. In this state CO2 has a very high solvent power, meaning the dye can dissolve easily and deeply into fibres, creating a vibrant colour.

The advantages and impacts are zero water use in dyeing and therefore zero waste water, zero processing chemicals, less energy, less dyestuff, a high level of colour consistency across batches of textiles and reuse of 95% of the CO2 within the process.

To give an illustration, one of our machines can process 800,000 kilogrammes of polyester per year, effectively saving 32 million litres of water and avoiding the use of 160,000 kilogrammes of chemicals. The total amount of CO2 used would be 5 million kilogrammes (5000 metric tonnes), 95% of which (4750 metric tonnes) would be recycled back into the process.

What stage are things at now?

We are still a start-up but the technology itself has been commercialised and we are ready to scale up further. Currently, we have nine machines in operation at the facilities of customers in Thailand and Taiwan, and we are installing three new machines in Vietnam. In these locations, the machines are used for dyeing polyester, production of which largely takes place in Asia. Our process works well with polyester.

In parallel we are developing our technology so that nylon, for example, can be dyed in the same machine. Other materials, such as cotton, that are highly water absorbent, are more challenging. Our business will evolve as we add new applications – meaning use of our machines to dye a range of different materials.

The main interest in the technology has come from the apparel and footwear textiles industry. Our customers are dye houses. For them, the investment costs for our machines are higher than for traditional equipment, but operational and environmental costs are lower. For take up of this technology in the supply chain, the support of brands, such as Nike, Adidas and Mizuno, is important. Those brands want their products to be more sustainable.

Our focus is on expanding take-up of the technology. For Europe, the technology represents a good eco-innovation export opportunity because a lot of footwear and apparel production has moved to Asia. However, there is also a great opportunity to bring production back to Europe with our advantage in technological know-how and high-end technical textiles. For example, the CO2-dyeing process can be used in markets such as automotive textiles, upholstery and technical textiles.

Can the process realistically be scaled up across the textiles industry?

Yes, this is exactly what is happening today for polyester dyeing. The technology expands by selling more dyeing machines. With our technology, there is no compromise between sustainability and profitability. However, adopting our technology does require confidence to invest today in a sustainable future. It requires a new way of thinking on behalf of the dye houses. We would like the roll-out of the technology to go faster. Our machines are assembled in the southern Netherlands by assembler VDL ETG Projects and there is sufficient capacity to scale up.

Is there any way government or the European Union could help?

Yes – for example by promoting sustainable textile production by applying favourable import duties. Legislation (or import penalties) on textile products that are produced less sustainably, or that contain certain chemicals, could also be considered. And support to help European textile production to convert to more sustainable production methods (from water-intensive to dry or no-water approaches) would be welcome. This could particularly be the case in more specialised areas, such as automotive textiles, upholstery and carpets, and technical textiles, in Europe.

Further information: http://www.dyecoo.com/co2-dyeing/