STEP 4

wash

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You might think that factories are washing your jeans because they want them to be nice and clean when you buy them in the shop, but that is not the case. There is so much going on in the laundry of a finishing factory: changing the feel, the colour, the texture, the properties and the look of garments.

what & how

After your jeans are cut & sewn, they’re “finished” where coatings are added or dye is removed for different looks. This is where we have seen a great deal of work in creating more sustainable options that use fewer resources and require less time. Ozone gas and lasers have been instrumental in removing indigo to create vintage washes and whiskering that was generally produced using harsh chemicals like Potassium Permanganate (PP SPray) and manual scraping.

Wastewater has been a major issue with processing denim. After denim has gone through the washing process, toxic sludge is left and disposed of in unethical and unsustainable ways.

They say in China you can tell the next trendy colour by looking at what colour the rivers are 😞

Effluent Treatment Plants are just as important in the washing process as in dyeing of the indigo. They use chemicals, bacteria, filters that need to be changed, and a lot of electricity, the best practice is definitely to avoid polluting the water, and when necessary then cleaning it. What exactly is removed from the water? Sludge is a combination of very small particles of cotton, particles of stones used in the wash, and chemicals. Do you have a dryer at home that requires you cleaning the filter at every usage? On an industrial scale that is the equivalent of sludge. The types of sludge of course depend on what initially goes in the water that is cleaned in the ETP: what fibres, chemicals and stones are used, and this will define the ways in which it can be disposed of.

After the garments are washed they also need to be dried. You can imagine that machines that can dry up to 100 jeans at a time need a lot of heat and power, meaning that they consume steam and electricity in vast amounts. Why don’t they hang the jeans like they do in Italian towns? Some factories have started installing conveyor belts that allow the jeans to be dry up to 85%, and then go in dryers for a very short time to become softer.

 
 

Support the ones that are disposing of waste in a humane manner such as turning old sludge into bricks that can be used for homes or using water filtration systems that allow them to recycle the water. There have been new developments where this sludge has been turned into fertilizer too!

Lasers can be used to create whiskering, distressing, holes, special designs and more. A computer program dictates the intensity and pattern, taking only a few seconds to complete the design. Check out my experience using one here! Lasers are extremely suitable for decolouring clothing, especially indigo on cotton, and create worn-out effects like whiskers or patterns, and abrasions to create rips and customized designs. This was originally done with sandblasting (literally blasting the jeans down with sand to wear them down). Lasers are able to do this with a minimum amount of energy. Chemicals, such as potassium permanganate, water and heat through steam are not necessary in this process. Therefore the footprint of laser technique is much lower, and no heavy manual work is needed.

Ozone Gas can be used in the washing process and requires up to 60 percent less water and less chemicals compared to the traditional method of using bleach denim. Ozone decomposes indigo and other dyes with its high oxidation potential, therefore it is a good replacement for sodium hypochlorite (bleach). No water or steam is required, it easily turns into oxygen or dissolves in pure water and is therefore not harmful to the environment. . This results in a water reduction, time reduction, fewer chemicals and less energy.

Less Water / No Water is always the goal, but new developments have shown us the possibility of using no fresh water at all! With Bio Membrane Reactor technology, domestic wastewater that is drawn from the surrounding communities is treated, as well as a new pipeline that will draw wastewater from the local municipal line. Not to mention without the use of any chemicals.

No More Pumice Stones! Instead there are companies making fake stones that provide beautiful results, but there are also natural enzymes that can create the same looks and lastly, there are mesh looking grills put into washers to achieve the look with NO STONES! Research is also being done into stones that don’t break down in the washing machine. Seriously tons of stones are shipped around the world, used once to give a nice feel to jeans, and then are discharged as sand and contamination to water? Yes.

Reducing microplastic pollution by integrating Xfiltra into washing machines to prevent 78% of microfibres from going down the drain. 

Companies like Sea Change are discovering ways to filter wastewater, remove the contaminants, and release the clean water back into the atmosphere or recycle it back into their facilities for use.

best practices

 

what can you do about it?

+ Look for denim that uses water recycling plants at the production facilities, and sustainable disposal of sludge.

 

+ Look for denim that uses more eco-friendly and water efficient processes like laser and ozone.

 

+ If a brand says it’s saving 90% less water than “traditional denim,” ask them how and what number they are comparing it to!

 

+ Buy vintage or secondhand!!!

 

certifications

Certifications to look for:

 

ZDHC was started in 2011, mostly as a response to the Greenpeace DeTox campaign. Part of the initial work established a Joint Roadmap to lead the apparel and footwear industry towards zero discharge of hazardous chemicals. ZDHC now is also a certification and classification of chemicals into tiers. All Bluesign and Organic certified chemicals are level 3 ZDHC (the highest level of sustainability). You should look out for these certifications:

+ WRAP

+ ISO14001

+ Fairtrade

+ Bluesign

+ Oeko Tex

+ GOTS

Need Help Finding a Vertically Integrated Supplier? Contact Simply Suzette here.

A big thank you to Virginia Rollando for contributing her supply chain expertise!