Potential sources of rare earth elements are sought after in the world by many researchers. Coal

ash obtained at high temperatures (HTA ) is considered among these sources.

The aim of the study was an evaluation of the suitability of the high temperature ash (HTA ) formed

during the combustion of bituminous coal from the Ruda beds of the Pniówek coal mine as an

potential resource of REY . The 13 samples of HTA obtained from the combustion of metabituminous

(B) coal were analyzed.

The analyses showed that the examined HTA samples varied in their chemical composition.

In accordance with the chemical classification of HTA , the analyzed ash samples were classified

as belonging to the following types: sialic, sialocalcic, sialoferricalcic, calsialic, fericalsialic,

ferisialic.

The research has shown that the rare earth elements content (REY ) in examined HTA samples

are characterized by high variability. The average REY content in the analyzed ashes was 2.5 times

higher than the world average (404 ppm).

Among rare earth elements, the light elements (LREY ) were the most abundant. Heavy elements

(HREY ) had the lowest share.

A comparison of the content of the individual rare earth elements in HTA samples and in UCC

showed that it was almost 20 times higher than in UCC.

The distribution patterns of REY plotted for all samples within their entire range were positioned

above the reference level and these curves were of the M-H or M-L type. The data presented indicate, that the analyzed ash samples should be regarded as promising REY

raw materials. Considering the fact that in 7 out of 13 analyzed ash samples the REY content was

higher than 800 ppm, REY recovery from these ashes may prove to be economic.

Ensuring access to a stable supply of a number of raw materials has become a serious challenge for domestic and regional economies with limited production, the EU economy alike. Reliable and unconstrained access to certain raw materials is an ever more serious concern. In order to tackle this challenge, the European Commission has established a list of Critical Raw Materials (CRMs) for the EU, which is regularly reviewed and updated. In its Communication COM(217) 490 final of September 13, 2017, the European Commission presented an updated list of 27 critical raw materials for the EU as a result of a third assessment based on a refined methodology developed by the Commission. Economic Importance (EI) and Supply Risk (SR) have remained the two main parameters to determine the criticality of a given raw material. The list of critical raw materials for the EU includes raw materials that reach or exceed the thresholds for both parameters set by the European Commission. The only exception is coking coal (included in the list of critical raw materials for the first time in 2014) which, although not reaching the economic importance threshold, has been conditionally kept on the 2017 list for the sake of caution. Should it not fully meet this criterion, it will be withdrawn from the list during the next assessment.

The article discusses the most important changes to the methodology used in the third review and their impacts on the coking coal criticality assessment. It presents the geographical structure of coking coal global production and consumption as well as the degree to which the EU is reliant on coking coal imports. Raw materials, even if not classified as critical raw materials, are essential for the European economy as they are at the beginning of manufacturing value chains. Their availability may change rapidly due to developments in trade flows or trade policy, which reveals the general need for the diversification of supply.

Rare earth elements are characterized by the high risk of their shortage resulting from limited resources. From this reason REE constitute a group of elements of special importance for the European Union. The aim of this study was to evaluate ashes from the burning of coal in fluidized bed boilers as an potential source of REY . Twelve samples of fly ash and bottom ash taken from power plants in Poland were analyzed. Tests have shown that despite some differences in chemical composition, the fly ash and bottom ash from fluidized beds could be classified as the calsialic, low acid type. It was found that fly ashes contained more REY than bottom ashes. Among REY , the light elements (LREY ) had the highest share in the total REY content in both fly ashes and bottom ashes. Heavy elements (HREY ) had the lowest content. The normalized curves plotted for fly ash samples within almost all of their entire range were positioned above the reference level and these curves were of the L-M or H-M type. The content of the individual REY in these samples was even twice as high as in UCC . The normalized curves plotted for bottom ash samples were classified as of L, L-M or H type. They were positioned on the reference level or above it. The content of the individual REY in these samples was the same or up to about 4 times lower than in UCC. It was found that the content of critical elements and of excessive elements in fly ash and bottom ash differs, which has an effect on the value of the outlook coefficient Coutl, and which is always higher in the case of fly ash than in the case of bottom ash. Nevertheless, the computed values of the outlook coefficient Coutl allow both fly ash and bottom ash from fluidized beds to be regarded as promising REY raw materials.

This paper presents the results of analyses of structure, volume and trends of demand for selected major critical raw materials (CRMs) suitable for the EU’s photovoltaic industry (PV). In order to achieve the EU’s goals in terms of the reduction of greenhouse gas emission and climate neutrality by 2050, the deployment of energy from renewable sources is of key importance. As a result, a substantial development of wind and solar technologies is expected. It is forecasted that increasing the production of PV panels will cause a significant growth in the demand for raw materials, including CRMs. Among these, silicon metal, gallium, germanium and indium were selected for detailed analyses while boron and phosphorus were excluded owing to small quantities being utilized in the PV sector. The estimated volume of the apparent consumption in the EU does not usually exceed 0.1 million tonnes for high purity silicon metal, a hundred tonnes for gallium and indium and several dozen tonnes for germanium. The major net-importers of analyzed CRMs were Germany, France, Spain, Czech Republic, the Netherlands, Slovakia and Italy. The largest quantities of these metals have been utilized by Germany, France, Belgium, Slovakia and Italy. The PV applications constitute a marginal share in the total volume of analyzed metal total end-uses in the EU (10% for silicon metal, 5% for gallium, 13% for germanium and 9% for indium). As a result, there is a number of applications that compete for the same raw materials, particularly including the production of electronic equipment. The volume of the future demand for individual CRMs in PV sector will be strictly related to trends in the development of PV-panel production with crystalline silicon technology currently strongly dominating the global market.

The assurance of future raw materials supply to the EU mineral industry has become, in recent years, one of the priority tasks of the EU Commission, geological surveys and several research centers. After many years of negligence, the problem of developing supply risk of many raw materials in Europe has been perceived, along with the menace to the EU economy competitiveness coming from dynamically developing countries such as China, India and others - basically of Asian origin. This has initiated a new mineral policy within the EU zone, referring mainly to non-fuels. One of the starting points for this activity has become the assessment of the EU mineral resources potential and identification of the raw materials that are critical for the harmonious and sustainable development and technological progress. The paper briefly presents the results of research work focused on the critical raw materials assessment, which were conducted by the Initiative for the Raw Materials Supply. Its core is the presentation of Polish mineral reserve base and its potential as a possible source of critical raw materials for the European Union. The criticality analysis was based on three categories, i.e.: economic consequences of the supply limitation, supply risk of reduction (fluctuation or disruption), and environmental risk referring to countries with weak environmental performance in order to protect the environment that jeopardize the supply of raw materials to the EU. For their quantitative assessment there were proposed three aggregated indices, while for the forecast purposes - 10-year period. The criticality ratio was determined for the 41 most important and most frequently used raw materials. On the grounds of the research made up to now, these raw materials were preliminary divided into three groups. As a critical to the EU economy, 14 raw materials of major economic importance were discriminated, i.e.: antimony, beryllium, cobalt, fluorite, gallium, germanium, graphite, indium, magnesium, niobium, PGM, rare earths, tantalum, and tungsten. They are characterized by high supply risk, which is mainly due to limited number of their sources - dominated by a few countries, in particular China. The risk of supply disruptions is boosted by low rate of utilization of secondary sources, and limited scale of substitution as well. The majority of the above-mentioned raw materials are crucial for the new technologies development. The remaining minerals arealso - though to a lesser extent - imperiled with a supply deficit. Despite they are also of economic importance, their indispensability for the advanced technologies development is relatively smaller. Taking into account the raw materials that are critical for the European Union economy, Poland cannot be considered as its resource base. The source of these raw materials are not only scarce in Poland, but also they are not produced, and their demand is now - and according to forecasts is going to be in the future - met by imports. However, the role of our country as a manufacturer of finished products from components of foreign origin is anticipated to increase. The raw materials in question are not considered exactly critical for Polish economy, as any industrial branch based upon their utilization has emerged so far. Therefore, they are of limited economic importance. Presumable utilization of very limited sources of above-mentioned critical raw materials in Poland could be anticipated in a perspective of at least 20 years. The most probable in this respect are the following: opening out the new Mo-W-Cu ore deposit Myszków, and the promotion of exploration works for similar deposits.

Municipal waste is a global issue and they are generated in all countries around the world. Both in the European Union and the United States, a common method of non-recyclable waste utilization is thermal incineration with energy recovery. As a result of this treatment, residual waste like bottom ash, air pollution control residues and fly ashes are generated. This research shows that residues from waste incineration can be a potential source of critical raw materials. The analysis of the available literature prove that the residues of municipal waste incinerators contain most of the elements important for the US and EU economies. Material flow analysis has shown that each year, the content of elemental copper in residues may be 29,000 Mg (USA) and 51,000 Mg (EU), and the amount of rare earth elements in residues exceeds their mining in the EU. In the case of other elements, their content may exceed their extraction by even over 300%. The recovery of elements is difficult due to their encapsulation in the aggregate matrix. The heterogeneous nature of residues and the many interactions between different components and incineration techniques can make the process of recovery complicated. Recovery plants should process as much of the residues as possible to make their recovery profitable. However, policy makers from the EU and the US are introducing new legal regulations to increase the availability of critical raw materials. In the EU, new regulations are planned that will require at least 15% of the annual consumption of critical raw materials to come from recycling. Therefore, innovative technologies for recovering critical raw materials from waste have a chance to receive subsidies for research and development.

Phosphate rocks and elemental phosphorus are considered to be critical raw materials mainly because of such parameters as the growing prices of phosphate fertilizers, the high concentration of producers limited to several countries in the world, the exceptional significance of phosphorus in agriculture and the inability to substitute it.
In Poland 100% of the demand phosphate rocks relies on import. The expansion and mining of the nation’s own resource base may be an alternative to import and a way to provide safety of supplies. Historically, phosphorites from the northern margin of the Holy Cross Mountains were extracted using the underground method, which was abandoned in the beginning of the 1970s due to the unprofitability of extraction. However, in eastern and south-eastern Poland, phosphorite concretions of the Eocene age occur at shallow depths, which can have local significance as mineral deposits and might be extracted in open-pit mines. The economics of mining in shallow opencasts do not require such stringent limiting parameters for phosphate deposits as those currently valid, which were established for underground mining conditions.
In this publication, the authors analyzed contemporary conditions for a cost-effective phosphorite deposit, including the price fluctuations of phosphate rock, a review of threshold parameters of deposits for phosphorite projects in the world, and the economics of open-pit ore extraction, where an aggregate mine with mixed extraction (partially from below the water table) was adopted as a point of reference.
As a result, new threshold parameters defining an ore deposit and its boundaries are proposed for Eocene phosphorites in Poland.