The industrial use of logging by-products also means that the timber obtained from logging is being put to more complete and profitable use. This article lists six products based on forestry by-products that are replacing fossil raw materials.
From cardboard mill to corn and... fields
Metsä Board, a subsidiary of Metsä Group, and Soilfood Oy are turning cardboard production by-products into soil improvers. The soil improver jointly produced by the companies, which is based on wood fibre, increases the organic matter content in arable land, improves water retention, and also sequesters carbon in the soil. Soil-improving fibres help protect watercourses because they can reduce phosphorus leaching from fields by up to 50%. Soilfood collects production waste from Metsä Board sawmills twice a day; it is also used for energy production, landscaping, and earthworks, such as constructing noise barriers and restoring landfills.
“In recent years, the demand for recycled nutrients and soil improvers has grown. Currently, market expansion is primarily limited by the availability of raw materials,” stated Sampo Jernefelt, Commercial Director of Soilfood, in a press release.
The cooperation between the two companies began in connection with a research project by the Natural Resources Institute Finland (Luke), which aimed to reduce the leaching of nutrients from fields into watercourses.
Battery production enters the “bio” era
In battery production, the majority of the required anode material will soon be producible from a biological raw material – dry coal. It is produced from lignin, which is a by-product of the cellulose production process and one of the world's largest sources of renewable carbon. The Stora Enso factory Sunila, operating in Kotka on the southern coast of Finland, is the world's largest producer of lignin. Until very recently, cellulose by-products, such as lignin, were burned to generate energy.
Lignin replaces non-renewable graphite used in batteries. A lignin battery can be charged 2-3 times faster than a conventional graphite battery. The new technology also provides higher energy density, reducing the need for charging and, consequently, the number of charging points and the amount of technology required for them. It is estimated that in 2030, the demand for anode materials in Europe will be approximately one million tonnes per year, and four million tonnes globally.
Renewable energy from pellets
Stora Enso uses by-products from sawmills to produce pellets at its pellet plant in Varkaus, eastern Finland, as well as at six of its other production facilities in Sweden, Latvia, Estonia, and the Czech Republic.
Sawdust, dry woodchips, and shavings – the remnants of woodchips produced at sawmills – are turned into pellets used in district heating plants, greenhouses, and manufacturing facilities. As pellets are a form of renewable energy, their use in heating is increasing, and they can perfectly replace fossil energy sources such as coal and oil. In the pellet production process, wood is ground into a homogeneous mass and, if necessary, mixed with starch and water to improve stability. The main binding agent in pellets is lignin.
Lignin for plywood bonding
In the manufacture of plywood, phenol-based adhesives can be replaced with lignin. The company UPM has long been developing more environmentally friendly adhesive technology. The properties of plywood products made using this technology are equivalent to those manufactured using traditional methods.
“Developing a bonding technology using lignin has been our long-term goal. We have now achieved a breakthrough that is the most significant innovation in the field of plywood adhesives in the last fifty years,” explains Susanna Rinne, Vice President of Strategy and Business Development at UPM Plywood.
Transport fuel from a cellulose mill
Another by-product of the cellulose process is crude sulphate methanol, which can be refined into biomethanol; this, in turn, can be used as a biofuel component suitable for transport vehicles. The raw material is produced at the Metsä Group Äänekoski mill in central Finland. It is then refined by the company Veolia, which is building a biomethanol plant next to the Metsä Group facility. Production is scheduled to begin there in 2024.
“It is sometimes thought that the cellulose industry is very conservative, although cellulose production is actually driving ideas for new products, such as those based on biochemicals,” says Mikael Lagerblom, Vice President (Sales, Europe) at Metsä Fibre, to the Metsä Group customer magazine Fibre.
Labels from cellulose production residues
Raw materials for labels made by UPM are derived from residues of the cellulose production process. The label material has exactly the same properties as fossil-based plastic. The production process for the label raw material uses UPM wood-based naphtha, which is obtained from tall oil produced during the cellulose process. The innovation is based on consumer demand for packaging where traditional fossil-based plastics are replaced by sustainable materials.