Long-term global availability of steel scrap

Primary steelmaking involves CO₂-intensive processes, but the expansion of secondary steel production is limited by the global availability of steel scrap. The present work examines global scrap consumption in the past (1870–2012) and future scrap availability (2013–2050) based on the historical trend. The results reveal that (i) historically, the consumption of old scrap has been insufficient compared with the amounts of discarded steel, and (ii) based on historical scrap consumption, the future availability of scrap will not be sufficient to satisfy the two assumed cases of steel demand. Primary steelmaking is expected to remain the dominant process, at least up until 2050. Under the reference-demand case of 2.19 billion tons in crude steel production by 2050, the total production of pig iron and direct reduced iron could reach 1.35 billion tons. Consumption of old scrap could reach 0.76 billion tons. Because the availability of scrap will be limited in the context of the global total, it is important to research and develop innovative low-carbon technologies for primary steelmaking and to explore their economic viability if we are to aim for achieving large reductions in CO₂ emissions from the iron and steel industry.     

Copper recycling and scrap availability

According to existing estimates, available old copper scrap has more than tripled over the past 40 years. Secondary production (that is, copper produced from recycling old scrap), however, has only doubled. Indeed, over the past 10 years, while copper consumption and primary production have continued to expand briskly, while available old scrap has increased by over 35%, secondary production has actually stagnated.For a world concerned with sustainable development and the quality of the earth's environment, this performance is disappointing and in need of explanation. Other things being equal, one would expect the amount of recycling to increase with the availability of scrap, as many econometric models of the world copper market developed over the past several decades explicitly assume.The key to understanding sluggish growth in secondary production, this paper argues, is distinguishing carefully between (1) the flow of old scrap that arrives each year from products reaching the end of their useful lives during the year and (2) the available stock of old scrap that was not recycled during earlier years presumably because it was too costly to do so. Using an econometric model, the paper shows that old scrap stocks, which have contributed most of the increase in available old copper scrap over the years, have a very modest impact on secondary production. Old scrap flows have a much greater effect, but they account for only about 4% of the available old scrap for any given year.     

Quantification of Chinese steel cycle flow: Historical status and future options

China is the largest steel producer and consumer around the world. Quantifying the Chinese steel flow from cradle to grave can assist this industry to fully understand its historical status and future options on production route transformation, capacity planning, scrap availability, resource and energy consumption. With the help of the systematic methods combined dynamic MFA (material flow analysis) with scenario analysis, the Chinese steel cycle during the first half of the 21st century was quantified and several thought-provoking conclusions were draw. In the past decade, lots of pig iron or molten iron was fed into EAF (electric arc furnace) and the scrap usage of EAF fluctuated slightly. Thus, the real scrap-EAF route share is much lower than the EAF production share. On the other hand, we reconfirmed that the scrap supply in China will rise significantly in the future. Meanwhile, the secondary production route share will grow sharply and exceed primary production share before or after 2050 depending on our options. The scrap recycling rate and construction's lifetime play a vital role in this trend. In the end, an intensive discussion on production capacities’ adjustment and energy and resource consumption was conducted and relative policy suggestions were given. It is worth noting that scrap usage is crucial to future energy saving and emissions reduction of Chinese steel sector and its energy consumption might peak as early as 2015.     

Environmental consequences of recycling aluminum old scrap in a global market

Nowadays, aluminum scrap is traded globally. This has increased the need to analyze the flows of aluminum scrap, as well as to determine the environmental consequences from aluminum recycling. The objective of this work is to determine the greenhouse gases (GHG) emissions of the old scrap collected and sorted for recycling, considering the market interactions. The study focused on Spain as a representative country for Europe. We integrate material flow analysis (MFA) with consequential life cycle assessment (CLCA) in order to determine the most likely destination for the old scrap and the most likely corresponding process affected. Based on this analysis, it is possible to project some scenarios and to quantify the GHG emissions (generated and avoided) associated with old scrap recycling within a global market. From the MFA results, we projected that the Spanish demand for aluminum products will be met mainly with an increase in primary aluminum imports, and the excess of old scrap not used in Spain will be exported in future years, mainly to Asia. Depending on the scenario and on the marginal source of primary aluminum considered, the GHG emission estimates varied between −18,140 kg of CO₂ eq. t⁻¹ and −8427 of CO₂ eq. t⁻¹ of old scrap collected. More GHG emissions are avoided with an increase in export flows, but the export of old scrap should be considered as the loss of a key resource, and in the long term, it will also affect the semifinished products industry. Mapping the flows of raw materials and waste, as well as quantifying the GHG impacts derived from recycling, has become an essential prerequisite to consistent development from a linear toward a circular economy (CE).     

Based on material flow analysis: Value chain analysis of China iron resources

Iron is an important basic resource for national economic development in China. It is of great strategic importance for the sustainable development of China's economy to study the utilization and circulation status of iron resources. In this paper, using the material flow and value chain analysis method, we quantitatively analyzed the value flow of iron resources in China. According to the value chain and price theory of element M, a value stream diagram of iron resources corresponding to the substance flow chart was plotted. Based on the previous material flow analysis result of iron resources, the diagram quantitatively depicted the value of the circulating flow of iron resources in China in 2011. The results show that by recycling materials, the value of the circulating flow of iron resources can bring considerable economic benefits to both producers and consumers. In the production stage, the expenditures of the entire economic system was reduced by 91.77 billion RMB by circulating iron and the income increased by 95 billion RMB by recycling home scrap, which was generated in the crude steel production stage. In the use stage of iron and steel products, the recycling of old scrap enabled the entire economic system to recover 370.78 billion RMB. It should be noted that analysis within a single framework of physical and economic characteristics of iron resources in the economic system can further extend the research chain of substance flow and value flow at the macro level, enhancing the economic value of substances flow research. In addition, by tracking and depicting the value flow cycle of elements, the improvement potentials and the value situations can be determined to provide useful information for conducting processing and technological innovation for waste minimization.     

Dynamic material flow analysis of steel resources in Korea

Material flow analysis (MFA) is an evaluation technique that systematically identifies the flows and stocks of materials within predefined spatial and temporal boundaries. In this paper, the steel resources in Korea are investigated using dynamic MFA. Iron ore and steel scrap are added as raw material components during the production processes of steel, which is then used in a variety of product groups such as construction products, transportation equipment, machinery/metal products, electrical/electronic devices, and other products through fabrication and manufacturing processes. When such product groups are discarded, they are either recycled or landfilled. With consideration for the lifetimes of various product groups in conjunction with steel resource flows in Korea, dynamic MFA is conducted on the flows of steel stock change and annual scrap generation. By 2020, these two flows are expected to increase by as much as 40% and 30%, respectively, compared to 2008, with transportation equipment, in particular, envisaged to experience high growth. At the current recycling rate, however, it will be hard to meet future scrap demand. According to the scenario analysis, 100% of this future scrap demand can be supplied domestically if the recycling rate is increased to over 70% for all product groups, except construction products and transportation equipment, which already have high recycling rates. By 2020, the reduction in scrap importation costs is projected to offer a financial gain of 2.3 billion dollars.     

Challenges and political solutions for steel recycling in China

The circular economy is an essential component of China's sustainable development. To promote the recycling of end-of-life products, the government has adopted various policies. Steel scrap is an important resource for steelmaking. Yet, the Chinese iron and steel industry uses less scrap to produce new steel compared to other large steelmaking countries. This article examines the reasons, why steel recycling is still relatively weak in China and what measures the government takes to improve the situation. We found that limited availability of scrap, high scrap prices, inadequate steelmaking capacities, industry fragmentation and unclear responsibilities for manufacturers are the main obstacles for steel recycling in China. The government is trying to improve steel recycling through tax incentives, import facilitation, support for supply, industry reorganization, and recycling parks, but with modest results.     

Economic and policy instrument analyses in support of the scrap tire recycling program in Taiwan

Understanding the cost-effectiveness and the role of economic and policy instruments, such as the combined product tax-recycling subsidy scheme or a tradable permit, for scrap tire recycling has been of crucial importance in a market-oriented environmental management system. Promoting product (tire) stewardship on one hand and improving incentive-based recycling policy on the other hand requires a comprehensive analysis of the interfaces and interactions in the nexus of economic impacts, environmental management, environmental valuation, and cost-benefit analysis. This paper presents an assessment of the interfaces and interactions between the implementation of policy instruments and its associated economic evaluation for sustaining a scrap tire recycling program in Taiwan during the era of the strong economic growth of the late 1990s. It begins with an introduction of the management of the co-evolution between technology metrics of scrap tire recycling and organizational changes for meeting the managerial goals island-wide during the 1990s. The database collected and used for such analysis covers 17 major tire recycling firms and 10 major tire manufacturers at that time. With estimates of scrap tire generation and possible scale of subsidy with respect to differing tire recycling technologies applied, economic analysis eventually leads to identify the associated levels of product tax with respect to various sizes of new tires. It particularly demonstrates a broad perspective of how an integrated econometric and engineering economic analysis can be conducted to assist in implementing policy instruments for scrap tire management. Research findings indicate that different subsidy settings for collection, processing, and end use of scrap tires should be configured to ameliorate the overall managerial effectiveness. Removing the existing boundaries between designated service districts could strengthen the competitiveness of scrap tires recycling industry, helping to reduce the required levels of product tax and subsidy. With such initial breakthroughs at hand to handle the complexity of scrap tire recycling technologies, there remains unique management and policy avenues left to explore if a multi-dimensional solution is to be successful in the long run.     

A future perspective on lithium-ion battery waste flows from electric vehicles

As a proactive step towards understanding future waste management challenges, this paper presents a future oriented material flow analysis (MFA) used to estimate the volume of lithium-ion battery (LIB) wastes to be potentially generated in the United States due to electric vehicle (EV) deployment in the near and long term future. Because future adoption of LIB and EV technology is uncertain, a set of scenarios was developed to bound the parameters most influential to the MFA model and to forecast “low,” “baseline,” and “high” projections of future end-of-life battery outflows from years 2015 to 2040. These models were implemented using technology forecasts, technical literature, and bench-scale data characterizing battery material composition. Considering the range from the most conservative to most extreme estimates, a cumulative outflow between 0.33 million metric tons and 4 million metric tons of lithium-ion cells could be generated between 2015 and 2040. Of this waste stream, only 42% of the expected materials (by weight) is currently recycled in the U.S., including metals such as aluminum, cobalt, copper, nickel, and steel. Another 10% of the projected EV battery waste stream (by weight) includes two high value materials that are currently not recycled at a significant rate: lithium and manganese. The remaining fraction of this waste stream will include materials with low recycling potential, for which safe disposal routes must be identified. Results also indicate that because of the potential “lifespan mismatch” between battery packs and the vehicles in which they are used, batteries with high reuse potential may also be entering the waste stream. As such, a robust end-of-life battery management system must include an increase in reuse avenues, expanded recycling capacity, and ultimate disposal routes that minimize risk to human and environmental health.     

The material resources for the iron and steel industries

The future supplies of iron ore, coking coal and ferrous scrap are discussed. There is no likelihood of the resources of iron ore being exhausted until well into the twenty-first century. Coking coal, on the other hand, is in shorter supply but it is being eked out by blending with non-coking coal and by making blast furnaces more efficient. Briquettes made completely from non-coking coal will play a part in iron making in the future. To ensure greater flexibility in steel making, hydrocarbons are being considered as possible substitutes for coal. Scrap has always played an important part in steel making and the amount recycled is increasing every year. But more effort is needed, for example, to ensure that the steel in car scrap is fully utilised and that refuse is efficiently recycled. Steel making increasingly demands the scrap to have few impurities and to be in uniform sized pieces. A cryogenic method of preparing such scrap is described. A futuristic way of extracting iron, non-ferrous metals and other saleeable by-products from refuse, by using redundant blast furnaces, is also discussed.     

Predicting future quantities of obsolete household appliances in Nanjing by a stock-based model

China has become one of the largest producers of obsolete household appliances (HAs) in the world. However, information on discarded HAs in China is deficient owing to the unavailability of reliable data. The estimation of future obsolete streams is a crucial issue for the establishment of efficient waste collection and recycling systems. The present study describes a prediction model to forecast future obsolete HAs on the basis of information of in-use stocks of HAs in households. The model was applied to a forecasting analysis of quantities of obsolete HAs from 2009 to 2050 in Nanjing, China. The results show that a total of about 76 million units (2.8 million tonnes) of obsolete HAs will be generated in Nanjing over the next 40 years. Discarded air conditioners, color TV sets, and personal computers will be the major contributors. The total discarded amount of major kinds of HAs will increase from nearly 1.0 million units in 2009 to a maximum of 2.1 million units in 2040, and then decrease slightly to 2.0 million units in 2050. Urban households will generate significantly more obsolete HAs (about 56 million units) than rural households, due to the difference in their HA possession levels. The results of this study should help the Nanjing municipality to develop the collection and recycling systems and facilities needed for the obsolete HAs generated in the future. From a methodological perspective, the stock-based model provides a suitable tool to predict the generation of discarded HAs in the future.     

Dynamic material flow analysis of zinc resources in China

Zinc is one of the most widely applied nonferrous metals in China. Study on the applications and recurrent situation of zinc resources is of great strategic importance for the sustainable development of China's economy. In this paper, a dynamic material flow analysis (MFA) method has been adopted to analyze quantificationally zinc resources in China, as well as to analyze and predict the quantity of zinc product scrap and their recycling situation. The weighted average method was applied to calculate average lifetimes of six major zinc products in China. The average lifetimes of battery, zinc oxide, zinc die-casting alloys, zinc material products, galvanized zinc and brass are 0.17, 5.3, 11.1, 12, 21 and 30 years, respectively. Assuming the lifetime of zinc product group obeys the Weibull distribution and the consumption of zinc products varies linearly with time, the future consumption and scrap generation of zinc products will increase continuously. It is expected that they would increase from 49% to 76% during 2004–2020, respectively. Assuming the recycling rate remains unchanged with time, the zinc old scrap index, both the theoretical and actual values, would continue increasing in China. The values are expected to reach 0.402 and 0.076 by 2020, respectively. Therefore, the regeneration resource of depreciated zinc is actually insufficient in China. According to the scenario analysis, the actual value of old scrap indexes is positively correlated with the recycling rate of zinc products. Because galvanized products are the largest consumption area of zinc products in China, the influence of their recycling rate on old scrap index is obviously larger than other zinc products. Through the analysis, this paper suggests that the increase of the recycling rate of zinc products could not only improve to a certain degree China's relative shortage of zinc resources, but greatly relive the supply pressure of zinc in the world.     

Metals recycling in the United States

Twenty-two metals for which secondary recovery is important, in terms of quantity and/or value, were compared and ranked for rate and efficiency of recycling, and availability of recycled metal. In general, their recycling rates trended upward over the period 1970–1993. Iron, aluminum, copper, gold, platinum, and lead accounted for most of the value of all secondary metal produced, while iron and steel dominated in terms of quantity produced and exported. The factors most influential on recycling rates are profitability, public support, organization of infrastructure, sortability, legislative support, and scrap purity. The share of supply accounted for by secondary metals is expected to surpass that of primary metals sometime in the next decade.     

Secondary copper recovery

Following a brief review of the economics of copper recycling, the technical details of secondary copper recovery are given, from classification and sampling of scrap through to the production of blister copper ready for electrolytic refining.     

Mechanical separation-oriented characterization of electronic scrap

The ever-increasing amount of electronic scrap and the steadily-decreasing contents of the precious metals used in electronics, as well as the ever-growing environmental awareness, challenges such conventional precious-metal-oriented recycling techniques as pyrometallurgy. Separation and beneficiation of various materials encountered in electronic scrap might provide a correct solution ahead. In this context, mechanical separation-oriented characterization of electronic scrap was conducted in an attempt to evaluate the amenability of mechanical separation processes. Liberation degrees of various metals from the non-metals, which are crucial for mechanical separation, were analyzed by means of a grain counting approach. It is found that the metallic particles below 2 mm achieve almost complete liberation. Particle shapes were also quantified through an image processing system. The results obtained show that the shapes of the particles, as a result of shredding, turn out to be heterogeneous, thereby complicating mechanical separation processes. In addition, separability of various materials was ascertained by a sink–float analysis. It has been shown that density-based separation techniques shall be viable in separating metals from plastics, light plastics (ABS, PS and PVC, etc.) from glass fiber reinforced resins and aluminum from heavy metals. Specifically, a high quality copper concentrate can be expected by density-based separation techniques. Moreover, FT-IR spectra of plastics pieces from the light fractions after the sink–float testing show that PC scrap primarily contains ABS, PS and PVC plastics with the density range of +1.0–1.5 g/cm³, whereas PCB scrap mainly contains glass fiber reinforced epoxy resins plastics with the density range of +1.5–2.0 g/cm³.     

Recycling opportunities in the UK for aluminium-bodied motor cars

The purpose of this paper is to review, and draw attention to, issues raised by the recycling of wrought aluminium from motor cars, even though the time horizon for significant arisings of such aluminium scrap is in the order of 20 years from now. Recycling of specific grades of wrought aluminium will be viable only when a means of positively identifying different types of scrap is available. A solution must be reliable, rapid, and low-cost; probably used in conjunction with a vehicle shredder. Such a system of identification will eliminate the need for costly hand-dismantling and segregation. Simple segregation of cast and wrought alloy will, however, be essential when wrought aluminium from car bodies dominates the scrap arisings. Such segregation will produce two high-value scrap products. The first of which will be similar to the A380 casting alloy specification, maintaining the current supply of this scrap, and the second will be a composite of wrought alloys. These issues are relevant to the aluminium scrap industry, which will have to accommodate future changes in the composition of the scrap it receives, and the motor industry, which may adopt in-house recycling of wrought alloy in order to offset the high purchase cost of aluminium.     

Assessing the potential of yield improvements, through process scrap reduction, for energy and CO2 abatement in the steel and aluminium sectors

Targets to cut 2050 CO₂ emissions in the steel and aluminium sectors by 50%, whilst demand is expected to double, cannot be met by energy efficiency measures alone, so options that reduce total demand for liquid metal production must also be considered. Such reductions could occur through reduced demand for final goods (for instance by life extension), reduced demand for material use in each product (for instance by lightweight design) or reduced demand for material to make existing products. The last option, improving the yield of manufacturing processes from liquid metal to final product, is attractive in being invisible to the final customer, but has had little attention to date. Accordingly this paper aims to provide an estimate of the potential to make existing products with less liquid metal production.Yield ratios have been measured for five case study products, through a series of detailed factory visits, along each supply chain. The results of these studies, presented on graphs of cumulative energy against yield, demonstrate how the embodied energy in final products may be up to 15 times greater than the energy required to make liquid metal, due to yield losses. A top-down evaluation of the global flows of steel and aluminium showed that 26% of liquid steel and 41% of liquid aluminium produced does not make it into final products, but is diverted as process scrap and recycled. Reducing scrap substitutes production by recycling and could reduce total energy use by 17% and 6% and total CO₂ emissions by 16% and 7% for the steel and aluminium industries respectively, using forming and fabrication energy values from the case studies. The abatement potential of process scrap elimination is similar in magnitude to worldwide implementation of best available standards of energy efficiency and demonstrates how decreasing the recycled content may sometimes result in emission reductions.Evidence from the case studies suggests that whilst most companies are aware of their own yield ratios, few, if any, are fully aware of cumulative losses along their whole supply chain. Addressing yield losses requires this awareness to motivate collaborative approaches to improvement.     

Current results and future perspectives for Japanese recycling of home electrical appliances

The Japanese system of recycling home electrical appliances has several unique aspects, including (1) a limited number of target appliances, (2) a recycling fee system that requires consumers to pay a recycling fee at the time of disposal, and (3) a direct recycling obligation for manufacturers, who have a physical, rather than a financial, responsibility for their end-of-life products. We studied data from 2001 to 2007 and found that the amount of four specified home electrical appliances and their materials that was recycled increased from about 319,249 tonnes in 2001 to about 447,262 tonnes—or 3.5 kg per inhabitant—in 2006. Recycling yield and development of recycling technologies have also improved. New recycling technologies have enabled a higher rate of material recycling of plastics (i.e., a closed-loop recycling). Improved eco-design, such as design for easier disassembly, has been promoted, and the higher quality of discarded appliances has enhanced the reuse market. Hazardous substances and fluorocarbons are being well managed. Problems with the recycling system include inelastic recycling fees, illegal dumping, illegal transfer by retailers, and the limited number of target appliances. Recycling fees could be reduced; this move might reduce the incidence of illegal dumping, as would engage stakeholders in collaborative efforts against illegal dumping. Illegal transfers could be reduced by improved traceability for retailers. Products such as liquid crystal displays, plasma display panels and clothes dryers have become increasingly common and should be also be targeted for recycling.     

Copper and copper alloys in the UK : Consumption and losses, 1920–1970

The authors consider consumption of copper in the UK using data from 1920 to 1970. They draw up an overall balance sheet which, it is hoped, provides a firm foundation on which to base the total availability of copper and against which could be balanced the scrap which was recycled.     

Global anthropogenic tellurium cycles for 1940–2010

Tellurium is increasingly used in solar photovoltaics in the form of cadmium–telluride (CdTe) thin films. There are concerns regarding whether tellurium availability could be a constraint on large-scale deployment of CdTe photovoltaics. The present work brings a new perspective to the discussion of tellurium availability by providing the first extant global tellurium cycles constructed with material flow analysis principles. The tellurium cycles, for 1940–2010, present information on the production, fabrication and manufacturing, use, and resource management stages during this period. The results of the analysis show that during 1940–2010 approximately 11 Gg of refined tellurium was produced. This represents about 4.5% of the tellurium that was extracted from the ground during copper mining. Almost 80% of the refined tellurium, 8.5 Gg, was dissipated into end-uses such as metallurgical additives to iron, steel, and nonferrous metals, and thereby lost to potential reuse. As of 2010, the in-use tellurium stock is estimated at 1.1 Gg, which mainly accumulated after 1990s with the increasing tellurium use in electronics, specifically photovoltaic and thermoelectric devices. Because tellurium is a byproduct of copper ores, its supply can be enhanced by more attention to recovery during processing of the copper parent. Tellurium can also, in principle, be recovered from end-of-life electronics; the increasing in-use stock indicates the potential for significant end-of-life recycling in the coming decades.