• Energy Research

Latin America has traditionally been a raw material supplier since colonial times. In this paper, we analyze mineral exports from an exergoecology perspective from twenty countries in Latin American (LA-20). We apply material flow analysis (MFA) principles along with the concept of the exergy replacement cost (ERC), which considers both quantity and thermodynamic quality of minerals, reflecting their scarcity in the crust. ERC determines the energy that would be required to recover minerals to their original conditions in the mines once they have been totally dispersed into the Earth’s crust, with prevailing technology. Using ERC has helped us identify the importance of certain traded minerals that could be overlooked in a traditional MFA based on a mass basis only. Our method has enabled us to determine mineral balance, both in mass (tonnes) and in ERC terms (Mtoe). Using indicators, both in mass and ERC, we have assessed the self-sufficiency and dependency of the region. We have also analyzed the mineral exports flows from Latin America for 2013. Results show that half of the mineral production from LA-20 was mainly exported. High-quality minerals, such as, gold, silver, and aluminum were largely exported to China and the United States. Extraction of high-quality minerals also implies higher losses of natural stock and environmental overburdens in the region.

SummaryThis paper makes a review of current raw material criticality assessment methodologies and proposes a new approach based on the second law of thermodynamics. This is because conventional methods mostly focus on supply risk and economic importance leaving behind relevant factors, such as the physical quality of substances. The new approach is proposed as an additional dimension for the criticality assessment of raw materials through a variable denoted “thermodynamic rarity,” which accounts for the exergy cost required to obtain a mineral commodity from bare rock, using prevailing technology. Accordingly, a given raw material will be thermodynamically rare if it is: (1) currently energy intensive to obtain and (2) scarce in nature. If a given commodity presents a high risk in two of the three dimensions (economic importance, supply risk, and thermodynamic rarity), it is proposed to be critical. As a result, a new critical material list is presented, adding to the 2014 criticality list of the European Commission (EC) Li, Ta, Te, V, and Mo. With this new list and using Sankey diagrams, a material flow analysis has been carried out for Europe (EU‐28) for 2014, comparing the results when using tonnage and thermodynamic rarity as units of measure. Through the latter, one can put emphasis on the quality and not only on the quantity of minerals traded and domestically produced in the region, thereby providing a tool for improving resource management.

The unique properties of certain metals have made them indispensable in manufacturing advanced technological devices and for use in the green economy. However, these metals are not infinite, and the average ore grades in mines have been decreasing in recent decades. This study examines energy consumption as a function of ore grade decline for Nickel, Cobalt, and platinum group metals (PGMs), using simulations created with HSC Chemistry software. A limit of recovery (LOR) for each commodity was also defined. A comparative analysis of the evolution of ore grades, energy costs, and market prices was additionally carried out. According to the simulations, extracting nickel from sulfide ore tailings would be profitable if the price doubled. As for Cobalt, it would only be feasible if the market price increased considerably. For PGMs, even if the ore grade reached the LOR, it would still be profitable to recover them under certain circumstances explored in the paper.

Abstract Decarbonizing world economies implies the deployment of “green technologies”, meaning a renovation of the energy sector towards using renewable sources and zero emission transport technologies. This renovation will require huge amounts of raw materials, some of them with high supply risks. To assess such risks a new methodology is proposed, identifying possible bottlenecks of future demand versus geological availability. This has been applied to the world development of wind power, solar photovoltaic, solar thermal power and passenger electric vehicles for the 2016–2050 time period under a business as usual scenario considering the impact on 31 different raw materials. As a result, 13 elements were identified to have very high or high risk, meaning that these could generate bottlenecks in the future: cadmium, chromium, cobalt, copper, gallium, indium, lithium, manganese, nickel, silver, tellurium, tin and zinc. Tellurium, which is mostly demanded to manufacture solar photovoltaic cells, presents the highest risk. To overcome these constraints, measures consisting on improving recycling rates from 0.1% to 4.6% per year could avoid material shortages or restrictions in green technologies. For instance, lithium recycling rate should increase from 1% to 4.8% in 2050. This study aims to serve as a guideline for developing eco-design and recycling strategies.

Abstract Latin America has always been a region of great interest not only for its rich-multicultural heritage, and diverse flora and fauna, but also for its natural resources that have become valuable commodities worldwide. In this paper an exergy-based analysis is used to investigate the cost of mineral depletion. By applying exergy replacement costs (ERC), a concept based on the Second Law of Thermodynamics, ERC determines the cost in exergy terms to recover minerals to its prior conditions with the current best available techniques when they have been completely dispersed after their usage. Such an assessment is a robust tool when evaluating natural resources in a country or region. We show that by using the above-mentioned methodology, it is possible to objectively quantify the loss of mineral wealth in Latin America associated to mineral extraction. Our study shows that the loss of mineral wealth in 2013 in the region was not compensated in comparison to the revenues obtained for the sale of minerals. Therefore, to establish a sustainable future scenario for the production of minerals in Latin America, a new framework for trading and management of fuel and non-fuel minerals is necessary.

A conventional passenger car demands almost 50 different types of metals, along other raw materials. Some of these metals, such as tantalum, indium, niobium or rare earths elements, are considered critical by the European Commission and many other institutions. Additionally, their functional recycling is practically absent. The transition to fully electric vehicles will require more electrical and electronic devices, motors and batteries, that will need an increasing amount of critical metals. A methodology has been developed to identify strategic elements for the automobile sector. This approach defines a variable called Strategic Metal Index (SMI) which is calculated for each metal. This index is the result of combining the following parameters: (1) Automobile sector demand with respect to world production; (2) known resources compared to total cumulative demand and (3) Supply risk. The index has been applied to 50 metals used by different types of vehicle powertrains. The assessment covers metal demand from 2018 to 2050 according to vehicle sales projections. Using this approach, the most strategic elements for the automobile manufacturing sector are Ni, Li and Co (used in batteries), Nd and Dy (permanent magnets), Tb (lighting and fuel injectors), Sb, Bi and and B (steel alloys, paintings), Au and Ag (electronics), In (screens) and Te (steel alloys, electronics). The search for substitutes, implementation of eco-design measures and the increase of the functional recyclability of these elements should be strongly encouraged in the sector.

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”.