Depletion Of Mineral Resources Research Articles

Highly Efficient 3rd Generation Multi-Junction Solar Cells Using Silicon Heterojunction and Perovskite Tandem: Prospective Life Cycle Environmental Impacts

In this study, the environmental impacts of monolithic silicon heterojunction organometallic perovskite tandem cells (SHJ-PSC) and single junction organometallic perovskite solar cells (PSC) are compared with the impacts of crystalline silicon based solar cells using a prospective life cycle assessment with a time horizon of 2025. This approach provides a result range depending on key parameters like efficiency, wafer thickness, kerf loss, lifetime, and degradation, which are appropriate for the comparison of these different solar cell types with different maturity levels. The life cycle environmental impacts of SHJ-PSC and PSC solar cells are similar or lower compared to conventional crystalline silicon solar cells, given comparable lifetimes, with the exception of mineral and fossil resource depletion. A PSC single-junction cell with 20% efficiency has to exceed a lifetime of 24 years with less than 3% degradation per year in order to be competitive with the crystalline silicon single-junction cells. If the installed PV capacity has to be maximised with only limited surface area available, the SHJ-PSC tandem is preferable to the PSC single-junction because their environmental impacts are similar, but the surface area requirement of SHJ-PSC tandems is only 70% or lower compared to PSC single-junction cells. The SHJ-PSC and PSC cells have to be embedded in proper encapsulation to maximise the stability of the PSC layer as well as handled and disposed of correctly to minimise the potential toxicity impacts of the heavy metals used in the PSC layer.

Life cycle assessment of bioethanol production from cattle manure

Biofuels can contribute significantly to reducing environmental damage. Lignocellulosic bioethanol can be an alternative to fossil fuels and is of great strategic importance to Brazil. In this context, the life cycle assessment (LCA) of bioethanol production from cattle manure (CM) was studied. CM is a biomass rich in cellulose that can be converted to glucose and other fermentable sugars. In the LCA, 1000 kg of CM were used as a functional unit of processing. The ReCiPe method and the EcoInvent libraries were used in SimaPro software version 7.3.2. We considered the following categories of impact: climate change, ozone depletion, terrestrial acidification, freshwater eutrophication, marine eutrophication, human toxicity, photochemical oxidant formation, particulate matter formation, terrestrial ecotoxicity, freshwater ecotoxicity, marine ecotoxicity, ionizing radiation, agricultural land occupation, urban land occupation, natural land transformation, water depletion, mineral resource depletion and fossil resource depletion. The categories damaged were human health, ecosystems and natural resources. The results obtained in the life cycle impact assessment (LCIA) and the proposed changes in the process contributed to the reduction of environmental impacts. The inputs/outputs that made the greatest contribution to environmental impacts were energy consumption, drying emissions, sulfuric acid in the pretreatment, buffer in the enzymatic hydrolysis and sodium phosphate in the fermentation. Bioethanol production from CM has a low impact on most of the categories and is a process that can be improved to reduce its impact mainly by changing the energy type. In the LCIA, it was observed that the CM bioethanol production eliminates the need for disposal treatment of the manure and uses residual raw material in a biofuel production, thus counterbalancing the environmental impacts of the bioethanol process.

Bottlenecks in rare metal supply and the importance of recycling – a Japanese perspective

ABSTRACTRare metals are less common metals that are generally perceived to be scarce. The media often presents one-track thinking on the depletion of mineral resources. Despite this common notion, the supply of most rare metals – including rare earth metals (REMs) – in terms of the amount of minerals available in known deposits is not a serious problem. Key factors that determine the supply of rare metals are the costs of mining and smelting, and related environmental destruction. These are the major practical constraints, rather than the amount of mineral deposits in the earth. When extracting rare metals from recycled feed material, harmful wastes generated from natural ore processing can be avoided. This is the primary advantage of the cyclical use of rare metal resources. In this article, bottlenecks of rare metal supply, and the importance of recycling, are discussed, using REMs as an example.

Resource depletion assessment of renewable electricity generation technologies—comparison of life cycle impact assessment methods with focus on mineral resources

Renewable energies are promoted in order to reduce greenhouse gas emissions and the depletion of fossil fuels. However, plants for renewable electricity production incorporate specifically higher amounts of materials being rated as potentially scarce. Therefore, it is in question which (mineral) resources contribute to the overall resource consumption and which of the manifold impact assessment methods can be recommended to cover an accurate and complete investigation of resource use for renewable energy technologies. Life cycle assessment is conducted for different renewable electricity production technologies (wind, photovoltaics, and biomass) under German conditions and compared to fossil electricity generation from a coal-fired power plant. Focus is given on mineral resource depletion for these technologies. As no consensus has been reached so far as to which impact assessment method is recommended, different established as well as recently developed impact assessment methods (CML, ReCiPe, Swiss Ecoscarcity, and economic scarcity potential (ESP)) are compared. The contribution of mineral resources to the overall resource depletion as well as potential scarcity are identified. Overall resource depletion of electricity generation technologies tends to be dominated by fossil fuel depletion; therefore, most renewable technologies reduce the overall resource depletion compared to a coal-fired power plant. But, in comparison to fossil electricity generation from coal, mineral resource depletion is increased by wind and solar power. The investigated methods rate different materials as major contributors to mineral resource depletion, such as gallium used in photovoltaic plants (Swiss Ecoscarcity), gold and copper incorporated in electrical circuits and in cables (CML and ReCiPe), and nickel (Swiss Ecoscarcity and ReCiPe) and chromium (ESP) for stainless steel production. However, some methods lack characterization factors for potentially important materials. If mineral resource use is investigated for technologies using a wider spectrum of potentially scarce minerals, practitioners need to choose the impact assessment method carefully according to their scope and check if all important materials are covered. Further research is needed for an overall assessment of different resource compartments.

Reductive leaching of jarosites by Aeromonas hydrophila

The mineral industry has suffered in recent years two significant impacts: the raise on energy cost and more strict environmental regulations. In parallel to the above restrictions, the depletion of high grade mineral resources leads the mining industry to search for alternative processes to avoid the high energy consumption and exploit low grade mineral deposits. Jarosite is a common product in mining and industrial operations. This basic sulfate mineral incorporates several metals by substitution and the dissolution of jarosite by dissimilatory iron-reducing bacteria influences the mobility of many heavy metals present in the mineral structure.In this work, the anaerobic bioreduction of three ferric solids (a biogenic mixture of ammonium and potassium jarosites, synthetic silver jarosite and natural gossan ore from RioTinto, Spain) by an isolated strain of Aeromonas hydrophila has been investigated. The release of ferrous ion indicated that the microbial reduction of jarosite takes place using lactate as electron donor. This process was accompanied by the subsequent secondary mineralization, leading to the formation of various iron-bearing minerals such as siderite, vivianite or magnetite. In addition, the influence of chelating agents (citrate and EDTA) and humic substances’ analogue (AQDS) as electron shuttling molecule were studied. While the chelants increased iron reduction and dissolution rate, the humic substances had no effect in the process. These results suggest that direct contact between A. hydrophila and minerals is required for the reduction of Fe(III).

Mineral Resource Depletion: A Coming Age of Stockpiling?

The gradual depletion of low cost (or “high grade”) mineral ores is generating increasing extractive costs and diminishing economic returns. The market reacts to this situation either with high prices, which depress demand, or with very low prices (as it is happening at present) that reduce or eliminate profits for the extractive industry, which is forced to reduce production. As a consequence, it is becoming increasingly difficult to manage the remaining mineral resources in such a way to ensure a sufficient supply for the economy and to avoid price shocks originated by the vagaries of the market or by social or strategic conflicts. This is particularly important for critical and rare metals, such as those needed by the electronic industry and for vital tasks such as the conversion and the transmission of electrical energy produced by renewable (e.g. photovoltaic) plants. One possible reaction to these problems is stockpiling, that is keeping mineral resources stored above ground and readily available in order to provide a buffer against price and supply shocks. The present paper discusses several ways in which the market of mineral resources could evolve, in particular the concept of a “metal bank” that could be used to manage the supply of rare and sensitive minerals.

Management of Strategic Resources as a Function of the Russian State

The function of the state — the management of strategic resources — becomes relevant on the threshold of the post-market economy and global depletion of mineral resources. The economic and political situation in the world is aggravated by the crisis of state system as the institution of management. In the article, the approach to the definition of the strategic resources of the state is presented. The examples of measures taken by the modern states to overcome this crisis are given. The thesis that the possession of strategic resources at the crisis moments of history becomes the essential tool in the political, economic and military confrontation of powers is proved. The question of the politicization of the market of mineral resources is brought up, and the current examples of such phenomenon are given. In the article, the arguments that the management of strategic resources in the near future will become the monopoly of the state are adduced. This implies a sharp weakening of the private part in this domain/sphere as it is in the interest of survival of the state and populace. The problem of the global depletion of mineral resources which influences the management of strategic resources is considered. The statistical analysis of mineral wealth in Russia and in the world is provided. Institutional (cultural) arguments for the sharp weakening of market tools in the management of strategic resources are analysed. The genesis of the study of the mentality of Slavs, Muslims and Hindus is given, according to which the only private possession of natural resources would be impossible and inadmissible. In the article, the various options of the growth of the state influence on the strategic resources in the new economic policy developed in Russia are offered.

Environmental impacts of high penetration renewable energy scenarios for Europe

The prospect of irreversible environmental alterations and an increasingly volatile climate pressurises societies to reduce greenhouse gas emissions, thereby mitigating climate change impacts. As global electricity demand continues to grow, particularly if considering a future with increased electrification of heat and transport sectors, the imperative to decarbonise our electricity supply becomes more urgent. This letter implements outputs of a detailed power system optimisation model into a prospective life cycle analysis framework in order to present a life cycle analysis of 44 electricity scenarios for Europe in 2050, including analyses of systems based largely on low-carbon fossil energy options (natural gas, and coal with carbon capture and storage (CCS)) as well as systems with high shares of variable renewable energy (VRE) (wind and solar). VRE curtailments and impacts caused by extra energy storage and transmission capabilities necessary in systems based on VRE are taken into account. The results show that systems based largely on VRE perform much better regarding climate change and other impact categories than the investigated systems based on fossil fuels. The climate change impacts from Europe for the year 2050 in a scenario using primarily natural gas are 1400 Tg CO2-eq while in a scenario using mostly coal with CCS the impacts are 480 Tg CO2-eq. Systems based on renewables with an even mix of wind and solar capacity generate impacts of 120–140 Tg CO2-eq. Impacts arising as a result of wind and solar variability do not significantly compromise the climate benefits of utilising these energy resources. VRE systems require more infrastructure leading to much larger mineral resource depletion impacts than fossil fuel systems, and greater land occupation impacts than systems based on natural gas. Emissions and resource requirements from wind power are smaller than from solar power.

Environmental impacts of balancing offshore wind power with compressed air energy storage (CAES)

Using Life Cycle Assessment, we discuss the environmental impacts associated with a Compressed Air Energy Storage (CAES) system as a means of balancing the electricity output of an offshore wind farm with a capacity of 400 MW. We model both conventional CAES and adiabatic CAES (ACAES), with target for baseload production of respectively 200 MW and 150 MW. For the CAES system, wind power production and natural gas combustion are main contributors to the assessed life cycle environmental impacts. For the ACAES system, wind power production and thermal energy storage are significant contributors. Compared with the impacts of wind power alone, and for the modeled energy storage size and target output, we find that CAES increases acidification, particulate matter, photochemical oxidant formation, and climate impacts significantly, but decreases eutrophication, toxicity, and mineral resource depletion impacts. ACAES moderately increases environmental impacts across all assessed impact categories, and impacts are sensitive to the required capacity of the thermal energy storage. In comparison with impacts from the average European mix, both storage configurations in our base case have low impacts per kWh electricity delivered to the grid, with the exception of mineral resource depletion.

Перспективи розвитку газовидобувної промисловості України

Nowadays the gas industry is one of the major components of the fuel and energy sector in Ukraine, and key issue of energy security is to increase domestic production of natural gas. The article analyzed the resource potential of gas production industry of Ukraine, where the current state and the main problems of development and operation were reviewed. It shows that in recent years the cause of decline in production of natural gas is not due to depletion of mineral resources but associated with geological exploration process imbalance, and one of the main causes of it was the reduction of investment in the sector. The results of predicted cost of gas production in Ukraine (average in the life cycle of conventional gas field), which is made using mathematical software and data program tools developed at the Institute of Energy of National Academy of Sciences of Ukraine. The forecast of natural gas production in Ukraine for the period until 2040 was developed. The evaluation of investments to gas production industry required to achieve the predicted production indicators was made. The main technological, economic and organizational measures to increase natural gas production in Ukraine were defined.

Multicriteria optimization of natural and recycled aggregate concrete for structural use

Recycling of concrete waste to produce recycled concrete aggregates (RCA) and its use in the production of structural concrete is the way towards reducing the depletion of natural mineral resources and the amount of construction and demolition waste being land-filled. The goal of this study was to determine the optimal choice of aggregate type and transport scenario in concrete production, employing a multicriteria optimization method taking into account technical, economical and environmental limits and constraints. Several concrete types with different type of used aggregate (river aggregate, crushed stone and recycled concrete aggregate) and different transport scenarios were analyzed. The environmental system evaluation criteria were chosen according to the Life Cycle Assessment methodology and the economical system evaluation criteria were determined in accordance with the current state of the ready-mixed concrete market in Serbia. The normative multicriteria optimization method (VIKOR method) was employed to determine the optimal solution. Analysis was performed for different decision making scenarios that gave emphasis to different criteria. Results have shown that concrete with a 50% replacement ratio of coarse aggregate with RCA can be presented as an optimal solution. Since natural aggregate concrete made with river aggregate was shown to have the lowest price, a further analysis was conducted to determine what economical measures should be undertaken in order to achieve cost equality of recycled and natural aggregate concrete. The analysis identified taxes on river aggregate, taxes on land-filling and subsidies for using RCA as viable measures.

Multi-objective optimization of waste and resource management in industrial networks – Part II: Model application to the treatment of sewage sludge

In the present article, the thermal treatment of digested sewage sludge generated in the Swiss region of Zürich is modeled and optimized from an environmental perspective. The optimization problem is solved using a multi-objective mixed-integer linear program that combines material flow analysis, process models, life cycle assessment (LCA), and mathematical optimization techniques. The treatment options include co-incineration in municipal solid waste incineration, co-processing in cement production, and mono-incineration with the prospect of phosphorus recovery. The model is optimized according to six environmental objectives. Five of the six single-objective optimal solutions involve splits over the treatment options. The results reflect the available treatment capacities and other constraints, aspects rarely considered in conventional LCA studies. Co-processing in cement production is used to the maximum extent possible when minimizing impacts on climate change, human toxicity, fossil resource depletion, and fully aggregated impacts (ReCiPe H/A), whereas mono-incineration with phosphorus recovery receives the bulk of the sludge when optimizing for ecotoxicity and mineral resource depletion. Four of the single-objective optimal solutions (minimization of fossil energy resource depletion and contribution to climate change, human toxicity, and fully aggregated impacts) outperform the reference case over the six impact categories considered, showing that the current situation can be improved in some environmental categories without compromising others. The results of the sensitivity analysis indicate that assumptions regarding the product systems displaced by recovered by-products are critical for the outcome of the optimization. Our approach identifies in all of the cases solutions in which significant environmental improvements can be attained.

A Comprehensive Recovery of Copper-Iron Experimental Research in the Copper Smelting Slag

With the depletion of mineral resources, more attention is paid on the secondary resources to recover valuable metals. In this paper, a research is carried out to recover copper and iron from copper smelting slag by flotation and magnetic separation. The influence of grinding fineness and collectors on flotation of copper are investigated. A copper concentrate is obtained by flotation and an iron concentrate is obtained by magnetic separation in the closed circuit flowsheet. The copper concentrate contains 18.86% Cu with a recovery of 72.36%, and the iron concentrate contains 52.24% Fe with a recovery of 70.87%.

Development of Local Weighting Factors in the Context of LCIA

Life Cycle Impact Assessment (LCIA) is a phase of the Life Cycle Assessment (LCA) in order to quantify various environmental impacts based on the inventory analysis. Weighting although is not the mandatory element of LCIA is the element in which local data becomes important. Potential environmental impacts and the importance of particular impacts can be quite significant among the countries or regions. Determination of the importance degree is possible by weighting of the selected environmental impact categories. Therefore, this study aimed to develop local weighting factors (WFs) by taking the environmental issues into consideration for the building materials produced in Turkey. And 11 environmental impact categories such as global warming, ozone depletion, acidification, photochemical ozone formation, eutrophication, fossil fuel depletion, mineral resource depletion, water depletion, land use, indoor air quality and waste were selected considering environmental impacts caused by the building materials and environmental issues in Turkey. And WFs of these categories for Turkey were determined by using a panel approach. Thus, it can be possible to assess environmental impacts of building materials by using local data.

A Spatial Study of Geo-Economic Risk Exposure of Russia’s Arctic Mono-Towns with Commodity Export-Based Economy

In the context of stagnating global economy mono-towns of Arctic Russia are especially exposed to uncertainty in their socio-economic development. Resource orientation of economy that formed in the 20th century entails considerable geo-economical risk exposure both for the towns and their population as well as for Russia's specific regions. In the 1990–2000s Russia’s Arctic regions were exposed to a systemic crisis which stemmed from production decline, out-migration, capital asset obsolescence, depletion of mineral resources and environmental crisis. This spatial study of geo-economic risk exposure of Russia’s Arctic mono-towns with commodity export-based economy was conducted at four dimensions - global, macro-regional, regional and local. The study of the five types of geo-economic risks was based on the existing approach, economic and socio-demographic risks being the most critical for the towns under consideration. Survey data will be used as the basis for recommendations related to prevention of potential jeopardies for the mono-towns of the region under consideration. The findings of this study will be included in the materials of survey N12-32-06001 “Russia’s Arctic Regional a Contemporary Model of Sustainable Development” funded by Russian Fund for Humanities Studies.

Enhancing Recycling of Construction Materials: An Agent Based Model with Empirically Based Decision Parameters

Recycling of construction material is a valuable option for minimizing construction & demolition waste streams to landfills and mitigating primary mineral resource depletion. Material flows in the construction sector are governed by a complex socio-technical system in which awarding authorities decide in interaction with other actors on the use of construction materials. Currently, construction & demolition waste is still mainly deposited in landfills, as construction actors lack the necessary information and training regarding the use of recycled materials, and as a result have low levels of acceptance for them. This paper presents an agent-based model of the Swiss recycled construction material market based on empirical data derived from the agent operationalization approach. It elaborates on how recycling of construction materials can be enhanced by analysing key factors affecting the demand for recycled construction materials and developing scenarios towards a sustainable construction waste management. Doing so it demonstrates how detailed empirical agent decision data were incrementally included in the ABM model. Raising construction actors' awareness of recycled materials as a decision option, in combination with small price incentives was most effective for enhancing the use of recycled materials. This could lead to a 50% reduction of construction & demolition waste streams to landfills, and significantly reduce the environmental impacts related to concrete applications. From a methodological perspective, although the agent operationalization approach provides a large empirical foundation, incremental model development turned out to be particularly important for the traceability of results and a realistic system representation.

The study of potable water treatment process in Algeria (boudouaou station) -by the application of life cycle assessment (LCA)

Environmental impact assessment will soon become a compulsory phase in future potable water production projects, in algeria, especially, when alternative treatment processes such sedimentation ,coagulation sand filtration and Desinfection are considered. An impact assessment tool is therefore developed for the environmental evaluation of potable water production. in our study The evaluation method used is the life cycle assessment (LCA) for the determination and evaluation of potential impact of a drink water station ,near algiers (SEAL-Boudouaoua).LCA requires both the identification and quantification of materials and energy used in all stages of the product’s life, when the inventory information is acquired, it will then be interpreted into the form of potential impact “ eco-indicators 99” towards study areas covered by LCA, using the simapro6 soft ware for water treatment process is necessary to discover the weaknesses in the water treatment process in order for it to be further improved ensuring quality life. The main source shown that for the studied water treatment process, the highest environmental burdens are coagulant preparation (30% for all impacts), mineral resource and ozone layer depletion the repartition of the impacts among the different processes varies in comparison with the other impacts. Mineral resources are mainly consumed during alumine sulfate solution preparation; Ozone layer depletion originates mostly from tetrachloromethane emissions during alumine sulfate production. It should also be noted that, despite the small doses needed, ozone and active Carbone treatment generate significant impacts with a contribution of 10% for most of the impacts.Moreover impacts of energy are used in producing pumps (20-25 GHC) for plant operation and the unitary processes (coagulation, sand filtration decantation) and the most important impacts are localized in the same equipment (40-75 GHC) and we can conclude that:– Pre-treatment, pumping and EDR (EDR: 0.-6 0 kg CO2 eq. /produced m3) are the process-units with higher environmental impacts.– Energy consumption is the main source of impacts on climate change.– Chemicals consumption (e.g. coagulants, oxidants) are the principle cause of impacts on the ozone layer depletion.– Conventional plants: pre-treatment has high GHG emissions due to chemicals consumption.

Life cycle environmental impact assessment of borax and boric acid production in China

Borax and boric acid are important primary products in China's boron industry. Their characteristic production technology has been adapted to the low ore grade. To analyze the environmental impacts of different borax and boric acid production processes and to promote cleaner production of boron industry, the life cycle assessment method of cradle-to-gate was applied in this study. GaBi4.4 software was used in the assessment and the environmental impacts were classified according to the CML2001 method. To show the degree of consumption of mineral resources and energy respectively, the abiotic depletion potential was divided into the mineral resources depletion potential and fossil energy depletion potential. A comparison between the mineral processing and entire system studied shows that energy consumption is important in life cycle environmental impacts. Boron production industries should refrain from using coal as their main heat source and try to use clean energy. A comparison between the borax production processes shows that the boron-rich slag is the cleanest material and that blast furnace gas can be used to reduce environmental impacts further in slow cooling link. A comparison between the boric acid production processes shows that flotation (I) is the cleanest process with the material of szaibelyite. Ludwigite should be processed after dressing to reduce the environmental impacts. Boron concentrate can be used to produce borax or boric acid as an alternative to szaibelyite but feasible production processes are still the focus of future research.

Fuzzy Comprehensive Evaluation of the Mode of the Mining Urban Economic Transformation

Mining city should be actively planning economic restructuring to guide urban development before the Depletion of mineral resources. How to target and selects transition models to achieve sustainable development in the mining city Future economic development is great significance. In the implementation of economic transformation of different mining town, resources, social, economic and other support to varying degrees, the effectiveness of different models of economic restructuring will be very different. By analyzing modes of the mining economy transformation, establishment of evaluation index, using fuzzy evaluation method to evaluate the effectiveness of different models of economic restructuring, this article provides a new way of thinking for the selection of the mode of the economic transformation.

Comparative LCA of recycled and conventional concrete for structural applications

Construction and demolition (C&D) waste recycling has been considered to be a valuable option not only for minimising C&D waste streams to landfills but also for mitigating primary mineral resource depletion. However, the potentially higher cement demand due to the larger surface of the coarse recycled aggregates challenges the environmental benefits of recycling concrete. Furthermore, it is unclear how the environmental impacts depend on concrete mixture, cement type, aggregates composition and transport distances. We therefore analysed the life cycle impacts of 12 recycled concrete (RC) mixtures with two different cement types and compared it with corresponding conventional concretes (CC) for three structural applications. The RC mixtures were selected according to laws, standards and construction practice in Switzerland. We compared the environmental impacts of ready-for-use concrete on the construction site, assuming equal lifetimes for recycled and conventional concrete in a full life cycle assessment. System expansion and substitution are considered to achieve the same functionality for all systems. The results show clear (∼30 %) environmental benefits for all RC options at endpoint level (ecoindicator 99 and ecological scarcity). The difference is mainly due to the avoided burdens associated to reinforcing steel recycling and avoided disposal of C&D waste. Regarding global warming potential (GWP), the results are more balanced and primarily depend on the additional amount of cement needed for RC. Above 22 to 40 kg additional cement per cubic metre of concrete, RC exhibits a GWP comparable to CC. Additional transport distances above 15 km for the RC options do result in environmental impacts higher than those for CC. In summary, the current market mixtures of recycled concrete in Switzerland show significant environmental benefits compared to conventional concrete and cause similar GWP, if additional cement and transport for RC are limited.