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The aim of the study was to explore the currently unexploited potential of agrifood waste and by-product biomasses for energy recovery and nutrient recycling, to mitigate climate change and eutrophication. The technical potential was assessed in two different case regions in Finland using two contrasting processing technologies, one oriented to recycle carbon and the other one to maximise replacement of fossil energy. The reduction in nutrient surplus through efficient recycling of biomass and consequent decline in fertiliser use was calculated. The reduction in GHG emissions was estimated based on the replacement of fossil energy and the diminished fertiliser manufacture. It was established that the full potential of use of the biomass to reduce GHG emissions can only be exploited in biorefineries that both produce energy and efficiently recycle nutrients. Such biorefineries have the potential to significantly mitigate climate change and prevent eutrophication. The potential reduction in GHG emissions corresponded to a third of agricultural emissions, and the reduction in fertiliser manufacture contributed with an additional fifth of that. The energy recovery corresponded to 5–10% of the fossil energy used in the regions, and the reduction in energy use for manufacture of fertilisers represented an additional 14–20% in comparison with that. The potential for nutrient recycling corresponded to 99–120% of P and 45–72% of N in the yields harvested in the regions. The choice of technology had a more pronounced impact on energy recovery, GHG emissions and C budget than on nutrient recycling.

Based on mass and energy balance calculations, this work investigates the possibility of recovering heat and nutrients (nitrogen and phosphorus) from municipal sewage sludge using pyrolysis or combustion in combination with a gas scrubbing technology. Considering a wastewater treatment plant (WWTP) with 65,000 t/a of mechanically dewatered digestate (29% total solids), 550 t/a nitrogen and 500 t/a phosphorus were recovered from the 4900 t/a total nitrogen and 600 t/a total phosphorus that entered the WWTP. Overall, 3600 t/a (73%) of total nitrogen was lost to the air (as N2) and clean water, while 90 t/a (15%) of total phosphorus was lost to clean water released by the WWTP. Both in combustion and in pyrolysis, the nitrogen (3%) released within thermal drying fumes was recovered through condensate stripping and subsequent gas scrubbing, and together with the recovery of nitrogen from WWTP reject water, a total of 3500 t/a of ammonium sulfate fertilizer can be produced. Furthermore, 120 GWh/a of district heat and 9700 t/a of ash with 500 t/a phosphorus were obtained in the combustion scenario and 12,000 t/a of biochar with 500 t/a phosphorus was obtained in the pyrolysis scenario. The addition of a stripper and a scrubber for nitrogen recovery increases the total electricity consumption in both scenarios. According to an approximate cost estimation, combustion and pyrolysis require annual investment costs of 2–4 M EUR/a and 2–3 M EUR/a, respectively, while 3–5 M EUR/a and 3–3.5 M EUR/a will be generated as revenues from the products.

Pallets are the tiny cogs in the machine that drive transportation in the global economy. The profusion of pallets in today’s supply chain warrants the investigation and discussion of their respective environmental impacts. This paper reviews the life cycle assessment studies analyzing the environmental impacts of pallets with the intent of providing insights into the methodological choices made, as well as compiling the inventory data from the studies reviewed. The study is a meta-analysis of eleven scientific articles, two conference articles, two peer-reviewed reports, and one thesis. The review was implemented to identify the key methodological choices made in those studies, such as their goals, functional units, system boundaries, inventory data, life cycle impact assessment (LCIA) procedures, and results. The 16 studies reviewed cumulatively analyzed 43 pallets. Mostly pooled (n = 22/43), block-type (n = 13/43), and wooden (n = 32/43) pallets with dimensions of 1219 mm × 1016 mm or 48 in. × 40 in. (n = 15/43) were studied. Most of the studies represented pallet markets in the United States (n = 9/16). Load-based (e.g., 1000 kg of products delivered), trip-based (e.g., 1000 trips), and pallet-based (e.g., one pallet) functional units were declared. A trip-based functional unit seems the most appropriate for accounting of the function of the pallets, as its purpose is to carry goods and facilitate the transportation of cargo. A significant amount of primary inventory data on the production and repair of wooden and plastic pallets are available, yet there are significant variations in the data. Data on pallets made of wood–polymer composites was largely missing.

There is an increasing call for products following circular economy principles. Despite growing pressure, understanding of the current situation and development vectors is largely missing. In this study, circular economy workshops were arranged for six industrial companies manufacturing electronics and operating in Finland to obtain an empirical understanding of the current state of circular economy implementation. During the workshops, each company assessed the state of the circular economy for a chosen product using a set of 51 circular economy strategies, i.e., the circularity deck. The results indicated that circular economy principles were implemented in only 25% of the cases. This is mostly related to the production of smaller, thinner, and lighter products. The results also indicate a large improvement potential of 36% for the participating companies. This is the share of cases that are planned for implementation. Those strategies mostly relate to the use of recycled inputs, the development of products made of a single material, and the design of products suitable for primary recycling. The least relevant or even irrelevant strategies were those related to the use of information technologies and artificial intelligence, despite electronic products being the enablers of such strategies for the other companies. Therefore, to further increase the circularity of electronic products and to meet the demands and interests of the manufacturing industry, research work on the technologies and services enabling the use of waste as raw materials should be emphasized to close the loops. Finally, the results imply the necessity for a more widespread assessment of circular economy strategies among companies, with consequent development of action plans for their implementation.

The aim of this study was to determine biorefining efficiency according to the choices made in the entire value chain. The importance of the share of biomass volume biorefined or products substituted was investigated. Agrifood-waste-based biorefining represented the case. Anticipatory scenarios were designed for contrasting targets and compared with the current situation in two Finnish regions. Biorefining increases nutrient and energy efficiency in comparison with current use of waste. System boundaries decisively influence the relative efficiency of biorefining designs. For nutrient efficiency, full exploitation of biomass potential and anaerobic digestion increase nutrient efficiency, but the main determinant is efficient substitution for mineral fertilisers. For energy efficiency, combustion and location of biorefining close to heat demand are crucial. Regional differences in agricultural structure, the extent of the food industry and population density have a major impact on biorefining. High degrees of exploitation of feedstock potential and substitution efficiency are the keys.

The prevailing large-scale use of chemical fertilizers has been affecting environmental degradation. a broken nutrient cycle has caused problems worldwide, which are related to the question of how to feed 9 billion people by 2050 while limiting human operations within the planetary boundaries. Indispensable nutrients, phosphorus (P) and nitrogen (N), often leak because of human activities, such as food production. efficient nutrient recycling can alleviate the problem. This study focuses on biofertilizers as a solution for the problem of a broken nutrient cycle. The study quantified the environmental benefits of using biofertilizers by calculating the carbon footprints of P and N in organic fertilizers by using the life cycle assessment (lCa) method on an existing biogas plant. The emissions from common production processes are allocated between products and co-products. however, whether a side flow is regarded as a co-product or waste is sometimes unclear. according to ISO 14040 and the greenhouse gas (GhG) protocol, if a substance does not have a value or the holder intends to dispose it, it can be regarded as waste. allocation of emission can be done according to parameters such as energy content, mass, or monetary value. The composted digestate was considered valuable; the allocation between biogas and nutrients was conducted according to the value of biogas and recycled fertilizers. The calculated carbon footprints were 0.8 kgCO2,eq./kg for N and 1.8 kgCO2,eq./kg for P, whereas the carbon footprints for mineral fertilizers were 1.9–7.8 kgCO2,eq./kg for N and 2.3–4.5 kgCO2,eq./kg for P. The reduction of GhG emission in organic fertilizer production in comparison with the emission in mineral fertilizer production was on average 78% for N and 41% for P. On the other hand, inclusion of N2O and Ch4 emissions from composting increases the carbon footprints of nitrogen and phosphorus but there is high uncertainty included with these emissions. The value of nutrients in the biofertilizers is also uncertain but the interest towards using of them is increasing in Finland. Publishers version