Washing and Scouring

At its most basic, scouring is a way of cleaning textile fibres. Wool that’s been shorn from a sheep is known as greasy, or raw wool. Just under 50% of raw wool isn’t actually wool at all: it’s grease, dirt, sweat (suint), burrs and seeds. Many other animal fibres also get washed: alpaca, goat hair and silk all get some level of cleaning. Angora rabbit is apparently an exception. Plant fibres have different processes, although decortated hemp does have a degumming stage.

So many ways to clean fibre!

Raw fibre often contains burrs that can scratch, and may contain disease that can transfer to humans, so it should be treated with caution. Cleaning removes the danger of disease and some burrs. There are many different traditions and ways to wash and scour a fibre. In this context, washing aims to remove large particles and sweat. Scouring uses heat to remove the oils from the fibre. Some people choose not to scour their fibre, because the oils can help the spinning process. Greasy wool is also more water resistant. Wool grease can develop a distinctive smell and gum up modern spinning equipment that is made for clean wool.

Raw huacaya alpaca fleece

Raw huacaya alpaca fleece

Some farmers wash their own fibre, using detergent. Ruth McGregor gives a good description of the process. Their products have what some people believe is a more natural ‘feel’. It’s particularly easy to do this with fibres like alpaca, which don’t have much grease. They do remain rather dusty though! Different sheep breeds have different levels of grease. For example, a Gotland sheep fibre will feel cleaner without scouring than a Merino sheep fibre.

Another way to clean wool fibres is to ferment them. This process uses the oils and sweat already present in the wool to ferment a soap. Zoe had me giggling and in awe over her experiment with this process.

How big business does it

Most commercial fibre you buy is scoured. There are two commercial scouring methods: an aqueous (water) process, and an organic solvent process. Scouring in Australia commonly uses the aqueous process. This process uses large amounts of water, heat and some detergent. The raw fibre gets dropped into 4 – 8 bowls (wash tanks) of hot/warm water and moved around to clean it. After each dunking, excess water is squeezed from the fibre before it drops into the next bowl. Each bowl contains cleaner water than the one that preceded it.

Wool-scouring

The commercial wool scouring process

1 ton of wool will usually contain:

  • 150kg of wool grease
  • 40kg of suint
  • 150kg of dirt (in Australia it averages around 180kg)
  • 20 kg of vegetable matter (although this is likely higher in Australia because we have lots of burrs in our grass)
  • 640kg of wool fibre.

Any grease in the washing water is spun off and sold to be made into lanolin. Solids can be separated from the wash and sent to landfill or composted for agricultural use. The washing water can be recycled up to a point, but scouring plants can still go through up to half a million litres of water a day. Scouring plants in Australia must treat water on their site until it’s safe to add to the sewerage system, or apply to the land. In Melbourne, all the scouring plants are city-based. This means they treat their water on site, then our excellent sewerage system takes over.

Water treatment

Water treatment

After scouring, fibre might be carbonised with sulphuric acid or bleached with hydrogen peroxide. Carbonising removes high levels of vegetable matter and softens the fibre. Bleaching brightens the colour of the wool. Not every plant undertakes these steps; I saw how they are done at Victorian Wool Processors.

acid bath and crushing machine

An acid bath (left), and crushing machine used during the carbonisation process

The final step is to dry the fibre, using drum rollers.

Drying tube

Drying tube

Environmental impact

Scouring has a big environmental impact. It uses large amounts of water (whether it is performed at home or commercially). Depending on the type of wool and equipment used, typically 8-20 litres of effluent liquids are created per 1kg of greasy wool. In some ways a commercial system is preferable, because it can recycle its water several times before disposal.

Waste water is high in potassium and nutrients, particularly nitrogen (although not always in a form accessible to plants). A consideration for Melbourne is that scouring works best with soft water. Our drinking water is soft, but our bore water (which local scouring plants may access as well) is hard. It’s possible to soften water, but those additives pose disposal challenges.

Electricity use is high if heat or extraction processes are applied. There are also many biological and chemical contaminants to deal with. The biological contaminants (like grease and weed seeds) often arrive with fibre from the farm. They need to be dealt with at the scouring disposal stage. The chemical contaminants also arrive direct from the farm (like inorganic fertilisers or biodegradable pesticides), or are added during cleaning (like detergents and bleaches). Sodium sulphate, a byproduct of carbonising, needs proper treatment before application to the land.

Dirt collected for fertiliser

Solid waste collected for fertiliser

The (old) Australian scouring effluent standards say that these contaminants can have a big environmental impact, but this can be mitigated with good management. The Global Organic Textile Standard prohibits use of endocrine disrupters (which can be found in detergents) and phosphates. It restricts bleaches to oxygen bleaches only. There’s a lot more detail in these standards that I can’t comprehend. I’d love to have someone’s more educated view on these documents and what they mean for this process.

What does this mean for consumers?

Washing and scouring fibres is a part of clothing manufacture. Few of our animal fibre clothes will skip this process. While fibres like alpaca and goat don’t need intensive scouring, in Australia they’re often processed like wool so the difference in impact is negligible. Even processing fibre at home will still use a significant amount of water, which needs to be disposed of appropriately.

A proactive approach could be to remember that scouring is a process we shouldn’t approach lightly. Let’s use it when we need something new, but try to reduce how often that happens.

Where does scouring happen in Melbourne?

EP Robinson, Geelong

Velieris, Braybrook, Melbourne

Victoria Wool Processers, Laverton North, Melbourne

edited on 11/1/16 to add details about disease risk in raw wool


IxCHeL

“You need to talk to Ixchel bunny. She has the most amazing angora fibres!” I’d just told a friend that I was researching my Fibreshed project. Hers was the second recommendation I’d had. That meant I was already curious by the time I first met IxCHeL’s owner Charly.

Charly is an eagerly anticipated fixture at many of Victoria’s fibre markets. I met her at the Handknitter’s guild fair in Coburg. She’s so friendly I had to wait in line to talk to her. Luckily for me, that meant I got talking to Wil, who’s been a great advisor to me ever since. Charly’s good at drawing good people to her.

Charly cuddling a 10 week old English angora kit. This gets it used to handling, combing and clipping.

I’d have loved to have visited Charly’s farm to check out her angora bunnies, but it would be too dangerous. Biosecurity on this type of fibre farm has to be extremely high to make sure the animals stay safe. Humans can be carriers of calici virus. This deadly disease, together with myxomatosis, is used in Australia to control wild rabbit populations. Unfortunately for domestic rabbits, the diseases don’t discriminate. Charly vaccinates against the strains of calici virus she can, but that doesn’t provide 100% cover. The myxomatosis vaccination is not permitted in Australia.

Instead, I quizzed Charly about her work in order to write this post. She also provided all the photos below.

IxCHeL farm

Charly has lived in at least four different continents. Love brought her to Australia. She has a beautiful little property in the Yarra Valley with her partner Paul. It’s tucked away between the mountains with a lush green paddock, plenty of water and wildlife.

The property’s small size means Charly can’t keep large livestock herds. Angora bunnies work here because they don’t need much space. It wasn’t just practical reasons that lead Charly to farm angora. She’s always felt an affinity with rabbits. Charly’s mother and grandmother were rug weavers, so she’s been immersed in fibre from a young age.

The Ixchel Farm and the Little Yarra River.

How to keep bunnies

A rammed earth enclosure under the veranda of the farmhouse has become the perfect bunny dwelling. During the day the angoras run in their enclosure. At night they’re kept safe in their bunny night cages. Underneath the night cages Charly has installed worm farms. They catch and process the rabbit’s droppings. The results enrich the farm’s veggie patches. This loop feeds the humans and bunnies on the property. Charly keeps her herd under 100 animals and doesn’t breed to sell for pets. This gives her a sustainable number to cover the needs of her fibre business. Each of her rabbits has a name.

Caring for angoras is very labour intensive. They need daily grooming and need their fur clipped at least every few months. Good grooming and maintenance helps reduce wool block. Charly’s herd has suffered several setbacks. Despite vaccinating against calici, a few years ago 75% of her herd was lost to a new strain of the virus. They’ve suffered from a different strain since then. They are currently on full alert because a new strain has been released. An additional new Korean calici virus strain is set to be released by the government this autumn. There are no new vaccines available. There have been reports of rabbit deaths in their local area.

Producing angora

Charly hand dyes, blends and spins tops and yarns on farm. She blends her angora bunny fibre with Navajo churro, Australian merino, wallaby and other rare breeds. Angorino is her angora and Australian merino blend. Her products are unique and only available in short runs, so you have to get in quick. Check the Ixchel blog for product updates every Friday night at 8 pm AEST. She also offers subscription clubs.

She works with Cashmere connections to do her bigger blends. IxCHeL is a great source of  rare breed fibres from around the world, such as vicuña, guanaco, qiviut, bison and rare sheep breeds like the North Ronaldsay and Norwegian Gra Troender.


Cashmere Connections

I stood outside Cashmere Connections, pondering their sign. It promised to process cashmere, angora, alpaca and cashgora. What is cashgora?! Is that an animal I haven’t heard of yet?

I called Trisha to let her know I had arrived; she came out from the workshop to let me in. She’s friendly and casual, but is a wealth of information and a patient explainer! We walked to the storage area, so I could see where the process begins.

The business

A cashmere farmer, Trisha and her husband developed Cashmere connections as a way to add value to their fibre product. They buy fibre direct from farmers and have it scoured at Velieris. Then they card and comb the fibres for worsted, semi-worsted and woollen spinning.

Cashmere connections processes smaller quantities of quality product. They concentrate on local and international niche markets of doona makers and spinners. Their tailored service is key to their ability to process so many different fibres well.

Entering the combing machine

Fibre being drawn into the combing machine

The process

Each kind of fibre is different: suri is dense and slippery; needing carding in small quantities or the machinery jams. Wool and cashmere don’t have the dust issues that alpaca has. Goat and alpaca fibres intended for spinning need dehairing to remove coarse hairs. That cashgora I was wondering about? It’s a cross between cashmere and angora goats.

The machinery at Cashmere connections is deliberately old. New machinery assumes a standardised product and can break fine animal fibres. Older machinery can be adjusted for each fibre type. Trisha even adjusts machinery for each individual batch according to its characteristics.

Before carding, anti-static is added to the fibres. A fine mist of water fills the room that holds the carding machines. The water relaxes the fibres and reduces dust. Fibres come out of carding as a sliver. This is fed into gilling machines three times, or more if suri fibre is being processed. The slowest part of the process is combing, before one last run through the gilling machine.

Exiting the combing machine

Exiting the combing machine. So light and lofty!

The potential

Under a cover in a corner of the workshop, Trisha unveiled a different piece of equipment. It is a repco spinner from the 1960s. Trisha’s been experimenting with is, in the hope she can offer worsted spinning as a service. Its different to other spinners I’ve seen, spinning 2 plys at a time. Trish’s got some lovely sample cones and knitted swatches. The process isn’t to a commercial standard yet. Fingers crossed it will be soon!

Cashmere connections has a small shop on site, but you can also find their products online. They sell beautiful throws and exquisite single fibre and blended tops. You might manage to meet Trisha in person; on occasion she holds a stall at the natural fibres market.

Yarn samples

Yarn samples