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.
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.