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The paper aims to implementation of Circular Economy in mineral processing in Poland. Circular economy represents a completely new approach to product life cycle, based on the departure from the linear model of “take – make – dispose” and turning to the circular or closed-circle model of economy. Challenges and opportunities of implementation of Circular Economy in Mining is presented. The VERAM project, financed by The European Union (by the EUR 1.4 million) to the project is described. The examples of good practice in the area of implementation of circular economy in Poland is presented (Tauron Wydobycie - wasteless mine and ZGH Bolesław - waste management)

In the present paper, the authors attempt to explain the importance of pH in soil environment studies and show what mistakes to avoid when measuring pH and interpreting the results obtained. The tests conducted (i.e., extraction in aqua regia, buffer capacity determination, and the impact of acidification on the amount of heavy metals extracted from soils) demonstrated how soil pollution and buffer capacity affect the pace of extracting cadmium (Cd), lead (Pb) and zinc (Zn) cations from heavily polluted and unpolluted soils following gradual acidification. It was shown that soil acidification caused a significant increase in metal mobility in the following order Cd > Zn > Pb and that the highest decrease in pH was observed after adding the first portion of acid. Further addition of acid caused a gradually lower decrease in pH. Soils from the polluted area presented a high buffer capacity. The control samples displayed a distinctly poorer resistance to pH changes in the soil environment. Special focus was placed on cadmium due to its high mobility in soils, even with neutral and slightly alkaline pH. The analyses revealed that in areas heavily polluted by long‐term industrial activity (Igeo > 5 for Zn, Pb and Cd), it is very important to conduct extensive geochemical studies related to the presence and circulation of particularly toxic elements. This is because every environmental factor, especially pH, may significantly affect their mobility, causing metal ions to become more or less active or increasing or decreasing environmental risk related to their presence. Highlights: Soil acidification caused a significant increase in metal mobility in the following order: Cd > Zn > Pb.A special focus needs to be placed on Cd due to its high mobility in soils (up to 70% of total concentration), even with neutral and slightly alkaline pH.A higher pH buffering capacity would lead to a lower increase in percentage of bioavailable pollutants with an increase in acidity. [ABSTRACT FROM AUTHOR]

Gasification in entrained flow reactors is now one of the most dynamically developed technologies of thermal conversion of coal. The basic, solid by-product of this process is slag, and in some cases also fly ash. In Poland, so far there have been no examples of industrial application of coal gasification. However, the high popularity of such systems in the world indicates the possibility of the appearance in Poland in the future, along with by-products of gasification. To pre-determine the possible future directions of management of this type of material, slag from coal gasification in foreign installation was obtained and tested. This article discusses the possibility of using slag from gasification of coal as a component of concrete and binding mixtures. The mechanical properties of such composites were tested because of the different content of the slag, the type of cement used, and the seasoning time. [ABSTRACT FROM AUTHOR]

Our article shows the results of research on ash-water solidified suspensions heated at high temperatures. The ash-water suspensions are used in underground coal mines to fill the voids and cavings resulting from exploitation. The heating of the solidified samples has been conducted to simulate conditions of the process of self-heating of residual coal substances. Similar conditions may also occur on the surface, e.g. during fires, and knowledge of the influence of the high temperatures on these type of materials may be useful when such substances are used as components of the building materials. For testing purposes we have used the ash from the fluidized bed combustion of lignite with and without the addition of the biomass. The conducted research covered the definition of the high temperature influence on the structure, leachability, phase composition, and mechanical properties of the suspension samples. [ABSTRACT FROM AUTHOR]

Biomass is a kind of fuel that is more and more often used in the energy industry. It supplements coal and allows it to meet the requirements of producing "green" energy and limit CO2 or sulphur emissions. Research refers to the ash originated from the combustion of the lignite with and without the wood biomass in the CFB boiler. This article shows the results of research into physical-chemical properties of fly ash obtained from the combustion of the lignite with and without the wood biomass (wood pellet). The possibilities of the use of this ash include in suspension technologies widely used in coal mines. [ABSTRACT FROM AUTHOR]

Abstract: The Kyoto Protocol signed by Poland obliges our country to reduce greenhouse gases emission in the period of 2008 to 2012 by about 6 below the 1990 level. One of the methods of reduction of CO2 emission is its binding via mineral carbonation. The paper presents the methodology of researches and findings on CO2 absorption by cement slurries prepared with the use of most commonly applied cement types. [Copyright &y& Elsevier]

Abstract: The ashes from lignite combustion are characterized by high CaO and free CaO contents and are a potentially interesting material for CO2 bonding, more particularly as theirs economical use is limited. The findings of CO2 absorption by suspensions prepared on the basis of ash from lignite combustion are presented in the paper. On these grounds CO2 sequestration potential via mineral carbonation in ash aqueous suspensions in Poland will be estimated. [Copyright &y& Elsevier]