A FEW FACTS
- Traditionally regenerated cellulose fibres for clothing are made from cellulose extracted from wood and bamboo, but can be produced from any source of cellulose.
- Companies around the world are now creating cellulose fibres from various types of agricultural waste.
- These fibres are claimed to be more environmentally friendly than conventional textile fibres because they utilise waste products, saving water, agricultural land and energy.
- By making use of waste, they may also end up being cheaper than other fibres.
When Dutch artist Jalila Essaïdi was looking to import some American goats, they produce a protein she needed for a ‘bio-art’ project, she hit an unexpected obstacle. When she approached farmers in the Netherlands about housing the goats they said they could only help if she could “solve the manure problem”.
In the Netherlands, almost all animal farms produce more poo than they can legally use as fertiliser and getting rid of the excess is expensive. But it is not just a Dutch problem. Disposing of the enormous volumes of manure produced every year is a huge global issue. According to recent research, more than 80 per cent of the four billion tonnes of dung produced every year by farm animals and humans comes from livestock, and it causes major environmental issues. Its decomposition produces harmful greenhouse and air polluting gases, while the run off of nutrients, such as phosphorus and nitrates, causes algae blooms that deplete oxygen from freshwater systems, killing fish and other organisms, and release dangerous toxins.
Undeterred, Essaïdi headed to her lab armed with a bucket of cow poo. “It soon became clear that there was this hidden gem locked away in manure that nobody spotted before: cellulose,” she says.
Cellulose is a structural component of cell walls in green plants. It is also used to make the clothing and textile fibres known as regenerated cellulose fibres, or more commonly rayon, viscose and modal. Traditionally cellulose is chemically and mechanically extracted from wood or bamboo, before being recombined and stretched to produce long fibres, but regenerated cellulose fibres can in theory be produced from cellulose from any source.
Manure from dairy cattle is roughly one-third cellulose. Using this novel raw material, Essaïdi has created a new regenerated cellulose fibre, Mestic, that can be used to make textiles and clothing.
In Italy one big source of agricultural waste is the citrus juice industry. Every year it produces thousands of tonnes of “pastazzo”, the bits of fruit left behind once the juice has been extracted.
In 2011, while sharing a flat in Milan, fashion designer Adriana Santanocito and social entrepreneur Enrica Arena had a “crazy” idea: they wondered if they could turn pastazzo into fabric. Arena explains that this could solve two problems, “the environmental and economic impact of citrus juice leftover disposal and the need for sustainable materials in the fashion industry.”
Now the two friends run a company together, Orange Fiber. At a pilot plant in Sicily they extract cellulose from citrus waste, using a process they developed with the Polytechnic University of Milan. This is then spun into fibres, before being turned into clothing by a select group of producers.
Arena says that the advantage of their fibre is that it “does not require dedicated yields alternative to food consumption”, but instead “reuses a waste, thus saving land, water and fertilisers” and reducing environmental pollution.
Cellulose can also be produced by fermentation. In Australia, one company has developed a novel process for creating it from liquid waste from the Indonesian coconut industry. Microbes feed on the nutrients in this waste and convert it into cellulose, which can be turned into fibres.
At the end of last year, Nanollose made their first item of clothing, a jumper, using cellulose fibres produced from coconut waste. They claim that the process will also work with any liquid that can be fermented, such as wine and molasses.
They says that technology like theirs is needed to move the fashion industry away from fibres like cotton and rayon, which both have a significant environmental impact. They add that their process uses very little water, agricultural land or energy. Michael Wills, from the company, says: “The only by-product is a diluted form of acetic acid, vinegar. This is often used as either a food additive or the base for organic cleaning materials.”
As well as the claimed environmental benefits, threads produced from waste could also be cheaper than traditional fibres. According to Essaïdi, raw materials make up 40 per cent of the cost of producing such fibres. “With Mestic we get our cellulose-source for free, farmers even pay us for processing their excess manure,” she says. “Our big vision is an actual refinery, not based on oil but on manure, that can produce fibres below current market price.”
Cover image: Vidar Nordli-Mathisen