The textile industry each year uses a substantial amount of chemicals and trillions of fresh water liters in the dyeing of clothing materials. The harsh reality is each year these chemicals and wastewater used in the textile dyeing process are then dumped untreated into rivers and oceans, creating a vast amount of pollution throughout the world.
Recently, three different waterless dyeing machines have been introduced to the textile industry: AirDye, ColorZen, and DyeCoo. In these three different waterless dyeing technologies, the use of water is cut drastically to nearly zero, the quantity of harsh chemicals is greatly reduced, and all employ faster dyeing cycles which lead to large drops in energy consumption.
Despite the benefits of greatly reducing pollution, water has been used for centuries in the textile dyeing industry; therefore many textile firms are hesitant to employ this new technology. Waterless dyeing machines are expensive to install and some machines can only be used with certain kinds of clothing materials. The reform of the textile dyeing industry is urgent in China and many surrounding countries’ textile industries. According to a 2012 report from the non-profit Institute of Public and Environmental Affairs (IPE) China’s textile industry discharges 2.5 trillion liters of wastewater into its rivers annually. Many toxic chemicals are found in the wastewater such as aniline, tributyltin (TBT), and perfluorooctane sulphonate (PFOS).
DyeCoo’s machines use carbon dioxide technology to color textile materials where no chemicals or salts are needed in the coloring process. The dyeing process is cut in half reducing energy and there is no wastewater discharge. 95% of the carbon dioxide used in the dyeing process can be recycled and used again in the machines.
In AirDye’s method, cloth is put into printing machines instead of the traditional method of dipping cloth into baths filled with dye and water. AirDye’s process is faster than the traditional dyeing method – therefore it uses 86 percent less energy and 95 percent less water.
ColorZen’s dyeing method changes the molecular composition of cotton fibers, which makes the cotton more receptive to dye. ColorZen’s technology uses half as much dye as the traditional method, 90 percent less water, and 75 percent less energy.
The biggest challenges to the widespread implementation of waterless dyeing machines in the textile industry are the cost and the specific cloths applicable. For example DyeCoo’s and AirDye’s machine technologies have proven successful in mitigating environmental hazards, they can only be used for now on polyester, not cotton. The Yeh Group in Thailand uses DyeCoo’s machines to produce clothes for Adidas. Adidas announced that the company was able to save 25 million liters of water by using one million yards of DryDye fabric to produce clothing. DyeCoo’s machines cost $2.5-4 million. With this high price point, only companies with large financial spending ability can afford the machines. In order for the technology to be widely adapted, the price must drop considerably.
See the link below for the complete article. //e360.yale.edu/feature/can_waterless_dyeing_processes_clean_up_clothing_industry_pollution/2775/