Mineral deposits are such type of assets, the valuation of which can be carried out in a very diverse manner. Methods and procedures for such a valuation are most often applied to mineral deposits with mineral reserves (according to the CRIRSCO classification), much less frequently and usually only using a comparative approach for undeveloped, initially recognized mineral deposits (with mineral resources). In Poland, a significant portion of mineral deposits, mainly of energy, metal and chemical minerals, are covered by the so-called mining property of the Treasury. At the moment, there is a lack of consistent and thoughtful management of these deposits. The appropriate methodology for valuing these deposits, which are at various stages of recognition (sometimes also of development), should be one of the key elements of such management. The State Treasury usually disposes of mining rights by “establishing” mining usufruct in the form of a contract, with the determination of remuneration for this establishment. The rules for determining remuneration for the establishment of mining usufruct are determined on the basis of an internal informal document of the Ministry of the Environment with very simplified rules for determining this remuneration, to a very limited extent related to the actual value of the deposit, which is also variable over time. This fee should be in close relation to the value of the mineral deposit valued at a given moment, taking the current conditions, including technological, environmental, formal and legal, and – in particular – market conditions into account. The valuation of mineral deposits covered by mining property, except for current needs in determining the basis for remuneration for mining usufruct establishing, should also be used to determine the value of these deposits annually as part of the State Treasury property and to present its results as part of the State Treasury Property Status Report. It is an open matter whether the methodology of valuation of the discussed mineral deposits should be based on accepted and widely used solutions for the valuation of mineral deposits for the purposes of business transactions or based on methodology of valuation of deposits as part of the planned system of Integrated Environmental and Economic National Account (up to date poorly developed). The paper presents the most important elements of both methodological approaches. It seems that the use of selected elements of each of these approaches would be advisable in this case.
The use of biomass in the energy industry is the consequence of ongoing efforts to replace Energy from fossil fuels with energy from renewable sources. However, due to the diversity of the biomass, its use as a solid fuel generates waste with diverse and unstable chemical composition. Waste from biomass combustion is a raw material with a very diverse composition, even in the case of using only one type of biomass. The content of individual elements in fly ash from the combustion of biomass ranges from zero to tens of percent. This makes it difficult to determine the optimal recovery methods. The ashes from the combustion of biomass are most commonly used in the production of building materials and agriculture. This article presents the elemental composition of the most commonly used biomass fuels. The results of the analysis of elemental composition of fly ashes from the combustion of forest and agricultural biomass in fluidized bed boilers used in the commercial power industry were presented. These ashes are characterized by a high content of calcium (12.3–19.4%), silicon (1.2–8.3%), potassium (0.05–1.46%), chlorine (1.1–6.1%), and iron (0.8–6.5%). The discussed ashes contained no sodium. Aluminum was found only in one of the five ashes. Manganese, chromium, copper, nickel, lead, zinc, sulfur, bismuth, titanium and zirconium were found in all of the examined ashes. The analysis of elemental composition may allow for a preliminary assessment of the recovery potential of a given ash.
The functioning of European economies and societies requires a stable and sustainable supply of mineral resources. For 10 years now EU has been developing raw materials initiative to secure European minerals supply. In many cases, areas with known or hypothetic mineral resources, are not sufficiently valued by society and authorities, remain unprotected and face competing land uses with the risk of becoming sterilized. MINATURA 2020 project was born out of a need to develop a harmonised framework which allow a common way of identifying “mineral deposits of public importance” (MDoPI) and their safeguarding via land use planning. The project has left a useful set of guidelines and proposals how to advance on the creation of a European network of MDoPIs to avoid sterilization of “deposits worth safeguarding”. In Poland, the need for legal protection of mineral deposits has been discussed intensively in recent years. Various proposals aimed at better system of mineral deposits safeguarding, especially those which should be recognized as of public importance, have been proposed. However, until now only a few coal deposits were recognized as strategic. Currently, the Polish National Mineral Policy is under preparation. Its overriding objective is to provide access to the necessary minerals, also in the longterm perspective. It assumes among others activities aimed at protection of mineral deposits regarding land use planning system. Paper presents scope and general results of MINATURA2020 project, with details on MINATURA2020 methodology implementation in Poland, Project of the Polish National Mineral Policy with its objectives and key pillars, position of MDoPIs in this Project, and – finally – expected future steps related to MDoPI safeguarding in EU and in Poland.
Overseas mining investment generally faces considerable risk due to a variety of complex risk factors. Therefore, indexes are often based on conditions of uncertainty and cannot be fully quantified. Guided by set pair analysis (SPA) theory, this study constructs a risk evaluation index system based on an analysis of the risk factors of overseas mining investment and determines the weights of factors using entropy weighting methods. In addition, this study constructs an identity-discrepancycontrary risk assessment model based on the 5-element connection number. Both the certainty and uncertainty of the various risks are treated uniformly in this model and it is possible to mathematically describe and quantitatively express complex system decisions to evaluate projects. Overseas mining investment risk and its changing trends are synthetically evaluated by calculating the adjacent connection number and analyzing the set pair potential. Using an actual overseas mining investment project as an example, the risk of overseas mining investment can be separated into five categories according to the risk field, and then the evaluation model is quantified and specific risk assessment results are obtained. Compared to the field investigation, the practicability and effectiveness of the evaluation method are illustrated. This new model combines static and dynamic factors and qualitative and quantitative information, which improves the reliability and accuracy of risk evaluation. Furthermore, this evaluation method can also be applied to other similar evaluations and has a certain scalability.
The purpose of the research was mapping, inventorization, and valorization of coal mining waste dumps from the mines of JSW SA company, for the needs of recovery of coal from the dump material as well as the reclamation and management of examined facilities. The valorization of post-mining waste dumps has been carried out using a methodology which considers the problems of reclamation, management, accessibility of the dumps as well as environmental hazards connected with disposing of mining and preparation wastes on the ground surface. An inventorization of 10 coal mining waste dumps coming from 6 mines of JSW SA including in their range 7 deposits: Borynia, Jastrzębie, Zofiówka, Budryk, Knurów, Szczygłowice and Pniówek was carried out. The source material within the localization of particular dumps was obtained from archival materials coming from coal mines and municipalities where the dumps are located. Verified data has been drawn on topographical map, which results in the map of coal mining waste dumps. The results of the valorization of the dumps comprise the defining of: the name of the dump, state of the dump, surface of the dump, accessibility, name of the coal mine from where the wastes come from, type of technical and biological reclamation and possibilities of coal recovery, which have been brought on the drawn map. Basing on collected and elaborated data, an attempt of defining of potential possibilities of recovery of coal from the dumps and connection of coal quality in the deposits of JSW SA and in waste material was made. The results of the research showed that in spite of preliminary information that a majority of the investigated dumps may be considered as potential facilities for coal recovery, ultimately the recovery is economically justified only in several cases (5 facilities).
Washing is very popular technological operation removing clay particles from aggregates. The amount of mineral washing sludges increases. Besides filling the excavations, there is no common method of their utilization. The usage of sludges from washing aggregates in building ceramics might be environmentally friendly way to utilize them. This paper presents laboratory research on two type of sludges: from dolomite and limestone aggregates washing. Selected properties of sludges such as water content, particle size distribution (sieve and areometric method), chemical composition (XRF), mineral composition (XRD), thermal properties (STA/EGA, dilatometry, heating microscopy) and stability of fired materials during steam exposure were determined. It was found that dolomite sludge contains more clay minerals and less carbonates, it is more finely grained than limestone sludge. Limestone sludge has large fluctuations in water content and has high content of potentially hazardous calcite grains. During heating up to 1300°C of both dried sludges decarbonation and sintering take place. Dolomite sludge softens, melts and flows below 1300°C. After firing sludges at 1000°C material made of limestone sludge is not resistant to steam. The obtained result suggests that dolomite sludge can be used in building ceramics technology without processing as main component of ceramic mass. Limestone sludge have to be ground before its application in building ceramic materials. Results suggest that it can not be used as the main raw material in ceramic masses, but only as an additive.
The article addresses the issue of conditions that the borrower is obliged to fulfill during the crediting process. These terms, the so-called covenants are built into credit agreements and are aimed at limiting banks’ risk when financing business entities. However, at the same time, covenants constitute conditions limiting the scope of use of bank loans. Covenants are very diverse. The principle hypothesis of the study assumes that the covenants differ according to the type of credit and the characteristic of the industry and the financial situation of the enterprise. In order to examine the hypothesis, an analysis of 25 credit agreements in three corporations and their subsidiaries was undertaken. These entities belong to fuel, mining and metallurgical sectors. At the same time, we observe the extent to which these covenants were kept during four quarters of 2016 and two quarters of 2017. Due to the confidentiality of the data contained in the loan agreements, the names of groups and their companies were kept confidential at the request of their management. Studies have also shown that abiding by non-financial covenants has been more difficult than abiding by financial covenants. In covenants, several contracts stipulated that a company cannot freely dispose fixed assets, restructure them or use leased assets which hinders the use of those asset to repay debt. One major obstacle was the fact that the company could not undertake any additional business beyond the existing one. This hindered the diversification of companies’ activities, which would improve their competitive position on the market. The author intends to conduct further research on covenants to highlight their flexible use and to increase the availability of bank loans to business entities.
During drilling through aquifers using the rotary drilling method with drilling fluid application, the phenomenon of formation clogging in near-well zone takes place. This leads to physical changes in pore spaces in consequence of the deposition solid phase particles originating from the drilling fluid. Due to this fact, filtration velocity in the clogged zones of the aquifer formation decreases, which results in increased pressure drawdown and decreased well hydraulic efficiency. Therefore, it causes a reduction of the well total capacity. The article consists of studies connected to the development of the mud which will constitute the basis for a complex mud system intended for hydrogeological drilling in different encountered geological conditions. In the framework of laboratory research, technological parameters of six, commonly applied in oil and gas industry, polymer agents as well as new agent developed at the Drilling, Oil and Gas Faculty AGH-UST in Krakow were examined. The undertaken studies showed that the new agent, marked as CAGEx, provides the required technological parameters and can be applied as a base for drilling muds intended for hydrogeological drilling. The undertaken industrial research of the new CAGEx drilling mud carried out while drilling water intake well, confirmed the great stability of its technological parameters as well as insignificant influence on rock permeability damage in filter zone. The water intake well is characterized by high hydraulic efficiency and does not require additional activation treatment.
Ore and non-ore mineralization in cracks filled with hydrocarbons in the dark grey Upper-Devonian limestone has been found in the Józefka quarry of Upper Devonian limestone and dolomite near the Górno village near Kielce at Holy Cross Mts. Poland. Hydrocarbons in the liquid form and iron and copper sulphides appears hear in the fault zone as joints filling. The wall rocks are impregnated by hydrocarbons giving them black color. Hydrocarbon impregnations appears also following the bedding planes The coexistence of ore mineralization and hydrocarbon suggests their common origin and migration from deep-seated sources, that may be the Silurian Ordovician or Lower to Middle Devonian black shales. The metallic-hydrocarbon compounds were suggested as metals carrier. Ore and non-ore mineralization in cracks filled with hydrocarbons in the dark grey Upper-Devonian limestone has been found in the Józefka quarry of Upper Devonian limestone and dolomite near the Górno village near Kielce at Holy Cross Mts. Poland. Hydrocarbons in the liquid form and iron and copper sulphides appears hear in the fault zone as joints filling. The wall rocks are spotty impregnated by hydrocarbons giving them black color. Hydrocarbon impregnations appears also following the bedding planes The coexistence of ore mineralization and hydrocarbon suggests their common origin and migration from deep-seated sources, that may be the Silurian Ordovician or Lower to Middle Devonian black shales. The metallic-hydrocarbon compounds were suggested as metals carrier.
Control of the technological processes of coal enrichment takes place in the presence of wide disturbances. Thus, one of the basic tasks of the coal enrichment process control systems is the stabilization of coal quality parameters at a preset level. An important problem is the choice of the controller which is robust for a variety of disturbances. The tuning of the controller parameters is no less important in the control process . Many methods of tuning the controller use the dynamic characteristics of the controlled process (dynamic model of the controlled object). Based on many studies it was found that the dynamics of many processes of coal enrichment can be represented by a dynamic model with properties of the inertial element with a time delay. The identification of object parameters (including the time constant) in industrial conditions is usually performed during normal operation (with the influence of disturbances) from this reason, determined parameters of the dynamic model may differ from the parameters of the actual process. The control system with controller parameters tuned on the basis of such a model may not satisfy the assumed control quality requirements. In the paper, the analysis of the influence of changes in object model parameters in the course of the controlled value has been carried out. Research on the controller settings calculated according to parameters T and τ were carried out on objects with other parameter values. In the studies, a sensitivity analysis method was used. The sensitivity analysis for the three methods of tuning the PI controller for the coal enrichment processes control systems characterized by dynamic properties of the inertial element with time delay has been presented. Considerations are performed at various parameters of the object on the basis of the response of the control system for a constant value of set point. The assessment of considered tuning methods based on selected indices of control quality have been implemented.
Steel and cast-iron products, due to their low price and beneficial properties, are the most widely used among metals; their consumption has become an indicator of the economic development of countries. The characteristics of iron raw materials, in relation to current metallurgical requirements, are presented in the present this article. The globalization of the trade and development of steelmaking technologies have caused significant changes in the quality of raw materials in the last half-century forcing improvements in processing technologies. In many countries, standard concentrates (at least 60% Fe) are almost twice as rich as those processed in the mid-20th century. Methods of quality assessment have been improved and quality standards tightened. The quality requirements for the most important raw materials ‒ iron ores and concentrates, steel scrap, major alloy metals, coking coal, and coke, as well as gas and other energy media ‒ are reviewed in the present paper. Particular attention is paid to the quality testing methodology. The quality of many raw materials is evaluated multi-parametrically: both chemical and physical characteristics are important. Lower-quality parameters in raw materials equate to significantly lower prices obtained by suppliers in the market. The markets for these raw materials are diversified and governed by separate sets of newly introduced rules. Price benchmarks (e.g. for standard Australian metallurgical coal) or indices (for iron concentrates) apply. Some raw materials are quoted within the framework of the commodity market system (certain alloying components and steel scrap). The abandonment of the long-established system of multi-annual contracts has led to wide fluctuations in prices, which have reached a scale similar to that of other metals.
A measuring system was developed for the measurement of ejector forces in the die casting process. When selecting the sensor technology, particular care was taken to ensure that measurements can be taken with a high sampling rate so that the fast-running ejection process can be recorded. For this reason, the system uses piezoelectric force sensors which measure the forces directly at the individual ejector pins. In this way, depending on the number of sensors, it is possible to determine both the individual ejector forces and the total ejector force. The system is expandable and adaptable with regard to the number and position of the sensors and can also be applied to real HPDC components. Automatic triggering of the measurements is also possible. In addition to the measuring system, a device and a method for in-situ calibration of the sensors have also been developed. To test the measuring system, casting experiments were carried out with a real aluminium HPDC aluminium component. The experiments showed that it is possible to measure the ejector forces with sufficient sampling rate and also to observe the process steps of filling, intensification and die opening by means of ejector forces. Experimental setup serves as a basis for future investigations regarding the influencing parameters on the ejection process.
The essence of ablation casting technology consists in pouring castings in single-use moulds made from the mixture of sand and a watersoluble binder. After pouring the mould with liquid metal, while the casting is still solidifying, the mould destruction (washing out, erosion) takes place using a stream of cooling medium, which in this case is water. This paper focuses on the selection of moulding sands with hydrated sodium silicate for moulds used in the ablation casting. The research is based on the use of Cordis binder produced by the Hüttenes-Albertus Company. It is a new-generation inorganic binder based on hydrated sodium silicate. Its hardening takes place under the effect of high temperature. As part of the research, loose moulding mixtures based on the silica sand with different content of Cordis binder and special Anorgit additive were prepared. The reference material was sand mixture without the additive. The review of literature data and the results of own studies have shown that moulding sand with hydrated sodium silicate hardened by dehydration is characterized by sufficient strength properties to be used in the ablation casting process. Additionally, at the Foundry Research Institute in Krakow, preliminary semi-industrial tests were carried out on the use of Cordis sand technology in the manufacture of moulds for ablation casting. The possibility to use these sand mixtures has been confirmed in terms of both casting surface quality and sand reclamation.
This article presents measurements of the thickness of alcohol-based coatings on sand foundry cores and moulds. These coatings were applied using two methods, the dipping method and the painting method. For the purposes of the study, a zircon alcohol-based coating was prepared with three different levels of nominal viscosity; very thin at 10s, average at 20s, and thick at 30s. The coating was applied to a core made of quartz sand and furan resin. The cores were made of sand with three different grain sizes; dL = 0.22 mm – fine sand, dL = 0.33 mm medium sand, and dL = 0.47 mm coarse sand. In the study, the thickness of the coating obtained to the core was measured immediately after application as well as after drying. Additionally, the extent of penetration into the intergranular spaces of the core matrix was measured. On the basis of this study, the impact of the grain size of the core matrix on the thickness of the coating and its penetration into the core was assessed. The thickness of coatings obtained using different application methods was also assessed.
The aim of the paper is to present the hydrodynamic, mass transfer and illumination characteristics of a laboratory helical-tube photobioreactor Biostat PBR-2S, commercially available and used in many laboratories in Poland and worldwide. The investigated hydrodynamics parameters were: mean liquid circulation rate, liquid velocity/residence time in the tubular part of the apparatus and mixing time, measured in the wide range of rotary speed of the circulation pump. The influence of the aeration intensity on these parameters was also checked. The volumetric oxygen and carbon dioxide transfer coefficients in the liquid phase and their dependency on the liquid circulation rate and gas inflow rate were determined. The experiments were performed in tap water and then in a real three-phase cultivation broth at the end of thermophilic cyanobacteria T. synechococus growth. For the final evaluation of the tested PBR there were series of test cultivations run under different conditions of illumination. The highest final concentration of the biomass of tested cyanobacteria reached the relatively high value of 4.38 g/dm3 of the dry biomass, although the process conditions were not fully optimized. The laboratory photobioreactor PBR-2S proved to be a good tool for investigations of microalgae cultivation processes. The presented results and practical observations may help to analyze and understand the mutual influence of the specific process parameters in the described PBR, especially during autotrophic organism cultivations.
On the basis of hydrogen peroxide decomposition process occurring in the bioreactor with fixed-bed of commercial catalase the optimal feed temperature was determined. This feed temperature was obtained by maximizing the time-average substrate conversion under constant feed flow rate and temperature constraints. In calculations, convection-diffusion-reaction immobilized enzyme fixed-bed bioreactor described by a coupled mass and energy balances as well as general kinetic equation for rate of enzyme deactivation was taken into consideration. This model is based on kinetic, hydrodynamic and mass-transfer parameters estimated in earlier work. The simulation showed that in the biotransformation with thermal deactivation of catalase optimal feed temperature is only affected by kinetic parameters for enzyme deactivation and decreases with increasing value of activation energy for deactivation. When catalase undergoes parallel deactivation the optimal feed temperature is strongly dependent on hydrogen peroxide feed concentration, feed flow rate and diffusional resistances expressed by biocatalyst effectiveness factor. It has been shown that the more significant diffusional resistances and the higher hydrogen peroxide conversions, the higher the optimal feed temperature is expected.
The article presents probable consequences for the protection of deposits and other mining needs, related to the entry into force of the Act of July 5, 2018 on the Facilitation of the Preparation and Implementation of Housing Investments and Accompanying Investments. This act introduces facilities for the preparation and implementation of housing as well as related projects, including the possibility of introducing investments incompatible with the existing local plans. In addition, it does so in a situation where land reserves for housing development, both in local plans and in studies of conditions and directions of spatial development, many times exceed the future needs of our country. The article presents the fundamental changes introduced by the Act to the existing planning and spatial planning system, as well as the risks associated with the mining industry. Among the latter, the following can be mentioned: lower stability of local law regulations, the possibility of resolving changes in spatial development at a very fast pace, without providing an effective way to inform subjects that may be threatened by these changes and increase the probability of the appearance of investments in the area of mining, the neighborhood of which may lead to limit or even liquidate these installations, due to even their disadvantages to housing. Some remedies have been proposed to mitigate some of the threats in the article. The Act in question was prepared and passed at an express pace, with a large opposition from many environments. At the same time, a number of legal solutions were applied in it, which were not applied in the Polish law. As a result, there are many doubts about the effects of its introduction.
The Act of July 5, 2018 on Facilitating of Preparation and Implementation of Housing and Accompanying Investments allows such investments irrespective of the existence of a local development plan or determination of use of land in the local development plan. In other words, the abovementioned investments may be implemented on land with a completely different designation according to the local development plan, as for example the mining of minerals. The location of the investment is decided by a resolution of the municipal council. If the planned location is to be situated within the boundaries of documented mineral deposits and the so-called „mining areas”, it needs, among others, to be agreed with the appropriate geological administration authority. Not taking a position within 21 days is considered as a consent. With reference to the deposits not covered by mining licenses, the Act does not indicate the premises that should be taken into consideration while providing such consent. There is a concern that this may lead to the development of the land in a way that will cause the subsequent extraction of the mineral impossible.
The mineral resources security is the most current and important problem. In the age of minerals, each deposit can be a source of an impulse for the development of innovative technologies. For this aim we should look for the rational and optimal management of resources. However, this is not a simple task, as indicated by subsequent years without the national mineral policy. The difficulty in securing deposits lies mainly in the complexity of this topic. It requires developing a vision, taking a direction, building appropriate tools and implementing them consistently. The article presents the current problems in the field of securing deposits against the announced national mineral policy. The authors reach for the analyses which were made in recent years regarding the country’s raw material management and indicate the scope of activities that should be taken to secure the deposits. What are the tasks in the draft of mineral policy and what is the scope of activities to secure the deposits that should be taken. The securing of deposits is primarily understanding the possibility of development deposits by their extraction. Therefore, it is misleading and inadequate to apply the term „resources pro-tection”. According to the authors it builds an unnecessary conflict between the mining industry and natural scientists who want to preserve the environmental resources untouched. The article also points out the main areas of action needed to effectively secure the resources, and also gives outline the solutions. Valorization works, preceded by verification of the quality of the geological documentations are of great importance for the creation of effective tools to protect resources. The result of these activities should be the long-awaited ranking list of deposits. Subsequently, the authors of the article suggest legislative changes in the field of spa-tial planning and environmental procedures.