Elina Huttunen-Saarivirta, Marjaana Karhu, Sami Majaniemi, Päivi Kivikytö-Reponen ja Tarja Laitinen
VTT Technical Research Centre of Finland Ltd
There are several advantages in safe and enhanced utilisation of secondary raw materials, especially side streams and residual materials. These include, among other things, reduction of waste and residuals and their treatment costs, lower procurement price of raw materials, wider availability of raw material resources, lower environmental loads and, in some cases, even landscaping related benefits. The utilisation of secondary raw materials would also allow the Finnish industry to work in the forefront of Cleantech, developing technologies that would allow societies to move from the linear raw materials economy to a circular one. The CloseLoop project delivers tools that facilitate better utilisation of secondary raw materials.
Secondary raw materials refer to raw materials collected and utilized through recycling, so-called side streams, as well as residual material, such as non-valorisable fraction released in the valorisation of the primary raw materials. These terms can be understood in different ways in various industry sectors. Their quantitative relationships vary, too. In paper industry, the primary raw material consists of wood and the secondary raw material include recycled paper or some of the many fractions ending up in energy production. In turn, in mining and metal processing industries, the mined mineral is the primary raw material, while secondary raw material streams cover the recycled metal, gangue minerals and rock, mine tailings and process slags as well as possible process water streams. These types of side-streams form a particularly attractive raw material reserve alongside the ever-diminishing and quality-wise lowering primary raw material reserves. In addition, some of the primary raw materials are highly dependent on non-EU imports, which creates a risk for their long-term availability and unstable price development. Consequently, the use of secondary raw materials also serves any nationally determined self-sufficiency goals.
The European Union has played a pivotal role in advocating circular economy issues. For example, the recent plastic recycling strategy of EU indicates clearly that the sustainability of the raw material resources as part of circular economy are subjects, which are of interest to both researchers and policy makers alike. The solution for the challenges related to the finiteness of economically viable materials sources is likely to be manifested in the formulation of future political actions at EU and national levels.
Indeed, there exist several hindrances in the sector of secondary raw materials’ usage, which can be removed via changes at EU level legislation. At present, secondary raw materials categorised as waste can not be moved from one EU country to another, unlike primary raw materials. Therefore, the the EU-wide market of the latter is not likely to emerge anytime soon. Technically, this results from the fact that waste materials are subject to different legislation than chemicals or products. In contrast, for secondary raw materials the practical differences between these terms may not be as black and white as in the case of primary raw materials. Another key challenge is the traceability and safety of the raw materials, such as ensuring that secondary raw materials do not contain toxic or harmful components. Furthermore, valorisation of side streams and residuals into high-quality products cannot be accomplished without new high level research and development that yield the enabling technologies, and attract long-term financial investments in the area.
At a global level, the benefits of utilising secondary raw materials clearly outweigh the disadvantages. As the utilisation technologies are further developed and establish their position, new possibilities will open up for the European and Finnish industries. This necessitates that the aspects of the circular economy of raw materials must be consciously taken into account in many strategic choices of the leading industrial actors. Currently, the most important thing is to raise awareness about the possibilities of using secondary raw materials and circular economy. In addition, these abstract terms need to be implemented as practices, through which they will be substantiated. One good way for companies wishing to benefit from the emerging circular economy materials (and money) flows is to get acquainted with the benefits of Life Cycle Assessment (LCA) methodology: The LCA reveals, in addition to the energy, water and CO2 footprints, the side streams available – that is, the potential secondary raw material reserves.
Virtual tools exist that enable the evaluation of potential and economic feasibility of raw/secondary material loops at all levels ranging from individual companies to complex multi-stakeholder networks (both existing and planned). The CloseLoop project has developed a virtual platform  for materials, energy, and other footprint impact assessment and optimization. This tool, called the Network LCA, can be utilized both at the level of an individual company and at the level of the entire network without the need for individual actors to disclose any sensitive information to each other directly. A similar approach has already been applied elsewhere, for example in the case of agricultural value chains [2,3]. The network LCA platform tool of the CloseLoop consortium allows companies and other interested parties to find answers to questions concerning, for example, how critical raw materials (CRMs) circulate in a network, what is the effect of increasing recycling rate of raw materials in manufacturing of a particular product, and how to optimise the resource efficiency in the network over the entire life cycle  of a product.