Search Results (5)

A conventional vehicle requires more than 50 different metals in its manufacturing, most of which are critical. Given this circumstance, enhancing sustainability from a raw materials perspective requires improvements in the disassemblability of car parts. This enhancement aims to yield metal-rich fractions, enabling the application of effective recycling processes for the recovery of critical metals. This helps avoid the downcycling that occurs in conventional shredding processes. The present study was undertaken to analyze the challenges associated with disassembling components of significant value due to their metal content. The methodology comprises two distinct main stages: an identification of critical car parts and an assessment of disassemblability. The selection of car parts was determined by the criticality of each one through the thermodynamic rarity indicator. Disassemblability was studied experimentally, encompassing three different levels. This classification defines the stages from extracting parts from the vehicle and obtaining recycling fractions in their purest form: ferrous metals, aluminum, non-ferrous metals excluding aluminum, and plastics. This methodology was implemented on two vehicles manufactured by SEAT: SEAT Leon models II and III. As a result, not only was disassemblability information about these car parts collected, but several ecodesign recommendations were also identified as valuable guidance for future designs, specifically aimed at enhancing metals’ recyclability. In conclusion, it must be acknowledged that contemporary vehicle design often prioritizes cost-effective manufacturing processes. However, this approach may compromise the disassemblability and recyclability of the product. The ongoing transition to electric vehicles necessitates a re-evaluation of design principles, particularly from the perspective of the circular economy. Full article

Using a thermodynamic approach, this paper identifies the most critical parts of a car, considering their composition. A total of 11 car parts that contain valuable and scarce materials have been selected using thermodynamic rarity, an indicator that helps assess elements and minerals in exergy terms according to their relative scarcity in the crust and the energy required to extract and refine them. A recyclability analysis using a product-centric approach was then undertaken using dedicated software, HSC Chemistry. To that end, the dismantling of these car parts into three main fractions was performed. Each car part was divided into non-ferrous, steel, and aluminum flows. A general metallurgical process was developed and simulated for each flow, including all the required equipment to extract most of the minor but valuable metals. Of the 11 parts, only 7 have a recyclability potential higher than 85%. By treating these selected car parts appropriately, the raw materials’ value recovered from the car can increase by 6%. The approach used in this paper can help provide guidelines to improve the eco-design of cars and can also be applied to other sectors. Ultimately, this paper uniquely introduces simulation-based thermodynamic rarity analysis for thermodynamic based product “design for recycling”. Full article

Rising prices in energy, raw materials, and shortages of critical raw materials (CRMs) for renewable energies or electric vehicles are jeopardizing the transition to a low-carbon economy. Therefore, managing scarce resources must be a priority for governments. To that end, appropriate indicators that can identify the criticality of raw materials and products is key. Thermodynamic rarity (TR) is an exergy-based indicator that measures the scarcity of elements in the earth’s crust and the energy intensity to extract and refine them. This paper uses TR to study 70 Mobile Phone (MP) Printed Circuit Boards (PCBs) samples. Results show that an average MP PCB has a TR of 88 MJ per unit, indicating their intensive use of valuable materials. Every year the embedded TR increases by 36,250 GWh worldwide -similar to the electricity consumed by Denmark in 2019- due to annual production of MP. Pd, Ta and Au embedded in MP PCBs worldwide between 2007 and 2021 contribute to 90% of the overall TR, which account for 75, 600 and 250 tones, respectively, and increasing by 11% annually. This, coupled with the short lifespan of MP, makes PCBs an important potential source of secondary resources. Full article

This paper presents a thermodynamic vision of the depletion of mineral resources. It demonstrates how raw materials can be better assessed using exergy, based on thermodynamic rarity, which considers scarcity in the crust and energy requirements for extracting and refining minerals. An exergy analysis of the energy transition reveals that, to approach a decarbonized economy by 2050, mineral exergy must be greater than that of fossil fuels, nuclear energy, and even all renewables. This is because clean technologies require huge amounts of many different raw materials. The rapid exhaustion of mines necessitates an increase in recycling and reuse, that is, a “circular economy”. As seen in the automobile industry, society is far removed from closing even the first cycle, and absolute circularity does not exist. The Second Law dictates that, in each cycle, some quantity and quality of materials is unavoidably lost (there are no circles, but spirals). For a rigorous recyclability analysis, we elaborate the exergy indicators to be used in the assessment of the true circularity of recycling processes. We aim to strive toward an advanced economy focused on separating techniques and promoting circularity audits, an economy that inspires new solutions: an in-spiral economy. Full article

The second law of thermodynamics and, specifically, exergy analysis have been traditionally used for the assessment and optimization of energy systems. Nevertheless, as shown in this paper, exergy could also constitute a powerful tool for the evaluation of mineral commodities. That said, new or re-defined exergy-based concepts need to be developed. This paper presents Thanatia as a baseline for evaluating the exergy of any mineral in the crust and opens the door to discuss the “thermodynamic rarity” concept as a basis for exergy analyses for mineral systems. Thermodynamic rarity is understood as the amount of exergy needed to obtain a given mineral from a completely degraded state, denoted as Thanatia. The rarer the mineral, the greater the associated exergy costs. It quantifies value, as it relates to concentration, chemical composition and cohesion, key aspects that determine whether a mine is exploitable. The theory further allows one to quantify the gradual loss of mineral capital on Earth as a consequence of “rarefaction processes” that occur at a mineral’s end-of-life, when a commodity is wasted, and at its beginning-of-life, where mining ore grades decline after extraction. Full article