By Karl-Henrik Sundström, CEO of Stora Enso
Timber, paper, cardboard. That roughly captures the material possibilities offered by a tree. After all, wood has been about since before human civilisation began and that's how it's always been. If there was more to it, we'd have figured it out by now, no?
Well what if I told you that every material that’s made with fossil fuels today can be made from a tree tomorrow?
And that, even today, forestry-products are being used in new and imaginative ways?
It’s a new approach to materials, but one that will become ever more pressing as we look to meet climate change targets and reduce waste as a society.
The theory
It makes sense when you think about it. Trees are made from three polymeric carbohydrates: cellulose, hemicellulose and lignin. Where we don’t use wood as a material itself, we tend to break it down into these constituent parts to make paper and fibre products. Of these, the traditional pulping process is intended to take out the cellulose fibres and the rest is usually burnt to provide electricity to pulp operations or sold.
However, all three parts of the tree can be valorised to make new products through mechanical or chemical processes. You can further process the cellulose part into many different applications already used today in textiles, pharmaceuticals, food and cosmetics.
This isn’t science fiction - it’s already been proven. Lignin has already been turned into carbon fibre in the lab, and micro fibrillated cellulose (MFC) is used to strengthen, lighten (by up to 10 per cent) and reduce raw material consumption in packaging paper board. Yet widespread roll-out is still to come as new processes and technologies take time to take root in the market.
So, on the one hand, we are using a fraction of wood’s potential as a material. On the other, we are using a fraction of its raw material bulk and burning much of the rest. There are still pieces of the puzzle to find before wood can become a full-fledged fossil-material challenger, but enough are in place to know that the puzzle is solvable.
The practice
What about right now though? What are the uses for wood products that might surprise you?
Lignin is already used as a replacement for oil-based phenolic materials in adhesives. Fluff pulp is used as a sustainable raw material by the hygiene industry for absorbent products such as tampons, protective pads, diapers and airlaid paper.
Cellulose derivatives are used in many of our everyday products – like in paints, cosmetics, food and pharma as additives and rheology modifiers.
Even clothing is being made from wood. Dissolving pulp is a specific type of wood pulp characterised by its high cellulose content, brightness and uniform molecular-weight distribution. These characteristics make it an ideal alternative material for the textiles industry.
Fibres such as rayon and viscose are familiar to many, yet most people are unaware of their forest origins or superior environmental record compared to alternatives. One kilogram of cotton requires 11,700l of water – 20-25 times more than needed for the same amount of viscose as well four times as much high-grade arable land. Moreover, cotton is one of the world’s largest markets for pesticides, which can degrade soil and water quality and threaten the health and biodiversity of local ecosystems.
Cotton will retain its position as the second most important textile fibre in 2017, meeting 26 per cent of the world’s total needs (behind polyester at 55 per cent). In comparison, the popularity of cellulosic fibres is paltry – just 5.4 per cent in 2015. However, the environmental benefits are clear and the business case is stacking up for tree-based fibres as consumers ratchet up their ethical expectations.
For example, Finnish fashion-house Marimekko has been working since 2014 with a new fibre created from birch cellulose, incorporating it into dresses and experimenting with printing techniques for the new fabric. The company – like much of the textile industry – is actively looking for more environmentally benign, wood-based fibres in the future.
The future
What next for wood-derived materials? The sky’s the limit.
The carbon-fibres that can be produced from tree products are suitable for the bodywork for aeroplanes. Also cars, wind turbines, boats - whatever calls for strong and light materials.
Biomaterials from wood also promise to create alternatives to plastic products and packaging that could revolutionise our societal approach to waste. Did you know that, with the number of plastic bottles we consume in a year, you could build a tower to the moon? 25 times. Only 14 per cent of plastic packaging is currently collected for recycling.
European Bioplastics, a trade association, predicts that by just 2018, 6.8 million tonnes of bioplastics will be produced globally that are at least partly derived from plants. Admittedly, that’s against the 20 million tonnes of regular plastics currently converted into packaging each year in the EU alone - but it’s still huge growth in a short time frame.
There are still technological and commercial barriers to widespread roll-out of some of these solutions. Arguably, we will also need social and attitudinal breakthroughs alongside these to make the switch to a more sustainable future. In any case, it takes time to commercialise new technologies and processes, find the right applications and build supply chains.
However, there are reasons to be optimistic. Many companies are actively looking for ways to introduce renewable materials into their products, packaging and supply chains. For example, renewable-non-renewable hybrid materials – biocomposites – are being developed and could become a real game changer as a more sustainable option to 100 per cent fossil fuel-based plastics.
The point
But what’s the point of all this? Fossil fuels are still cheap and plentiful. Surely it’s easier to keep doing things as we are - creating plastics and relying on carbon-intensive steel and concrete?
The answer, aside from the fact that fossil fuels may not always be cheap and plentiful, is of course: the environment.
Dependence on fossil fuels is environmentally destructive in so many ways. Whether it’s the damage done during their extraction, the contribution to global warming, or the mountains and oceans full of waste we are producing, few would agree that the status quo is the way to go.
Trees, by contrast, improve our environment and improve our wellbeing. They remove carbon and other greenhouse gases from the air and are completely biodegradable. You might think then, that cutting them down to use as materials is environmentally harmful. However, sustainable forestry takes a ‘cut one, plant two’ approach that can mean reforestation rather than deforestation. Moreover, younger, growing trees remove more carbon from the air than mature ones.
And of course, trees won’t run out - they’re a truly renewable resource.
So is it time to rethink wood as a material? Let’s stop limiting our imaginations to items we traditionally think of as wooden. After all, fossil fuels are biological matter - is it any wonder that we can create the same products from our forests given the right technological ingenuity? In many cases we can. In others, we are tantalisingly close. In all cases we should.
