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All life forms require phosphorus (P), which has no substitute in food production. The risk of phosphorus loss from soil and limited P rock reserves has led to the development of recycling P from industrial residues. This study investigates the potential of phosphorus recovery from sewage sludge and manure ash by thermochemical treatment (ASH DEC) in Finland. An ASH DEC plant could receive 46-76 kt/a of sewage sludge ash to produce 51-85 kt/a of a P-rich product with a P2O5 content of 13-18%, while 320-750 kt/a of manure ash could be supplied to produce 350-830 kt/a of a P-rich product with a P content of 4-5%. The P2O5 potential in the total P-rich product from the ASH DEC process using sewage sludge and manure ash is estimated to be 25-47 kt/a, which is significantly more than the P fertilizer demand in Finland's agricultural industries. The energy efficiency of integrated incineration and the ASH DEC process is more dependent on the total solid content and the subsequent need for mechanical dewatering and thermal drying than on the energy required by the ASH DEC process. According to the results of this study, the treated sewage sludge and manure ash using the ASH DEC process represent significant potential phosphorus sources for P fertilizer production.

Municipal solid waste (MSW) management is becoming increasingly popular around the world as a means of accommodating the increasing amounts of waste that the growing global population generates. China currently produces more MSW than any other country. As such, this area of the world is facing challenges on an unprecedented scale. MSW management in China is highly dependent on landfilling, and the development of sanitary landfills is currently a top priority for the Chinese government. Hangzhou is one of the most developed cities in China. In fact, in 2013, the amount of incinerated MSW in Hangzhou represented 56% of total MSW. MSW incineration is primarily performed via a process of co-incineration with coal because MSW has a low heating value. This paper employs a environmental impact assessment by LCA program to determine whether refuse-derived fuel (RDF) production and incineration can have a more positive impact on the environment than the co-incineration of MSW with coal in Hangzhou, China. According to the results, RDF production and incineration could improve Hangzhou's MSW management global warming potential from -33% to 0%, the acidification potential from -90% to 34%, and the eutrophication potential from -1 200% to 350% in comparison to the co-incineration of MSW with coal. The treatment of organic reject material from RDF production has a significant effect on the results; as such, it should be utilized in energy production rather than landfilled.

This article investigates the potential environmental impacts of four-layer printed circuit board (PCB) production from cradle to grave. The study starts with a lifecycle assessment of conventional PCB production. Then, the alternative materials of polyethylene terephthalate (PET), polylactic acid (PLA)/glass fiber composite and paper are investigated for the substrate. A conventional PCB adopts copper as the conductive material and requires an etching process. The environmental impacts of changing the conductive deposition method to an additive method by printing silver nanoparticles is studied. In a conventional PCB, electricity generation contributes 41% of the global warming potential (GWP) and 38% of the abiotic resource depletion (ADP), in the fossil category. By applying an additive manufacturing method, the GWP of PCB manufacturing can be reduced to 14% of that of the conventional method. A sensitivity analysis of silver recycling illustrates that a 40% higher silver recycling rate would decrease the GWP of silver material by about 48–60%. Uncertainty in the energy consumption of PCB production would alter the environmental impacts; however, even with the most conservative energy consumption in a conventional PCB production method, the environmental impacts of the additive method are about five times lower than those of conventional PCB production.

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.