This study discusses results of experiments on hydrodynamic assessment of gas flow through backbone (skeletal) porous materials with an anisotropic structure. The research was conducted upon materials of diversified petrographic characteristics – cokes. The study was conducted for a variety of hydrodynamic conditions, using air. The basis for assessing hydrodynamics of gas flow through porous material was a gas stream that results from the pressure forcing such flow. The results of measurements indicate a clear impact of the type of material on the gas permeability, and additionally – as a result of their anisotropic internal structure – to a significant effect of the flow direction on the value of gas stream. In aspect of scale transfer problem, a method of mapping the flow geometry of skeletal materials has been developed and usefulness of numerical methods has been evaluated to determine pressure drop and velocity distribution of gas flow. The results indicate the compliance of the used calculation method with the result of experiments.

The paper presents the results of studies on the changes in the PAHs concentration during pre-filtration and ultrafiltration (UF) processes. In the study, biologically treated wastewater (after denitrification and nitrification processes), discharged from the biological treatment plant and used in coke plant, was used. A gas chromatography-mass spectrometry (GC-MS) was used in order to qualify and quantify the PAHs. Sixteen PAHs listed by EPA were determined. The wastewater samples were collected three fold and initially characterized for the concentration of nitrate nitrogen, ammonium nitrogen, COD, TOC and pH. In the first step, wastewater was filtrated on the sand bed. Total concentration of 16 PAHs in the treated wastewater before initial filtration was in the range of 44.8‒53.5 mg/L. During the process the decrease in the concentration of the most studied hydrocarbons was observed. Concentration of PAHs after initial filtration ranged from 21.9 to 38.3 μg/L. After the initial filtration process the wastewater flew to the ultrafiltration module and then was separated on the membrane (type ZW-10). The total concentration of 16 PAHs in the process of ultrafiltration was in the range of 8.9‒19.3 mg/L. The efficiency of removal of PAHs from coke wastewater in the process of ultrafiltration equaled 66.6%. Taking into account the initial filtration, the total degree of removal of PAHs reached 85%. The obtained results indicate the possibility of using the ultrafiltration process with the initial filtration as additional process in the coke wastewater treatment.

The S-7 borehole log from the Sumina area (USCB Poland) revealed the presence of three basaltic veins

originating from a basalt dyke. Coal interlayers in the rocks surrounding the basaltic veins have been coked to

form natural coke. Photometric measurements revealed that the optical properties of the studied natural coke

samples are characteristic of semi-graphite (Rmax > 9%). The natural coke matrix of all of the analyzed samples

has a biaxial negative optical character. Vitrinite in the examined natural coke samples is characterized by a

lower optical anisotropy than that of the natural matrix and it has a biaxial positive optical character. Vitrinite

in almost all samples taken at locations more distant from the intrusion has a biaxial positive optical character.

A reversal of the changes of the true maximum vitrinite reflectance and bireflectance with changing distance

from the second basaltic vein has been observed. The temperature regime that acted upon the dispersed organic

matter located in the immediate vicinity of the intrusion, estimated on the basis of the selected experimental

data, is suggested to be higher than 750 °C.

Samples of active coke, fresh and spent after cleaning flue gases from communal waste incinerators, were studied. The outer layers of both coke particles were separately removed by comminution mechanism in a spouted bed. Analyses included density, mercury porosimetry and adsorption. The remaining cores were examined to determine the degree of consumption of coke by adsorption of hazardous emissions (SO2, HCl, heavy metals) through its bed. The differences in contamination levels within the porous structure of the particles were estimated. The study demonstrated the effectiveness of active coke in the cleaning of flue gases.

The efficient, stable and reliable operation of the blast furnace secures the proper quality of coke, which is one of the basic components of the blast furnace charge. In modern blast-furnace technology, when using substitute fuels, i.e. coal dust, the role of coke is extremely important. For this reason, the demands placed on its quality increase. Domestic coking plants have a limited base of Polish high quality coking coals at their disposal, therefore the full use of their coking properties is extremely important. The grain composition of the coal blend is one of the basic factors affecting the quality of the produced coke. This influence depends on the quantity and quality of coal components that make up the blend. In the conducted research, 21 coking coals, differing significantly in the degree of rank and origin (Polish and overseas coals), it was shown that the separated grain classes differ in properties, both coking properties and the degree of devolatalization during heating. In analyzing the obtained results, it was observed that the grain volume growth occurs essentially in the temperature range between the beginning and the maximum of fluidity. It has been shown that there is a linear correlation between the temperature corresponding to maximum fluidity and the temperature at which the maximum rate of evolution of volatiles enters. The presented phenomena accompany the emergence of coal expansion pressure during the coking process and they are its primary causes. The presented results can be an important guide for preparing the milling of coal for the coking process.

The article presents current state of the structure of hard coal enrichment plants in Poland, taking the capacity, the range of grain enrichment and the type of equipment used into account. This data were presented in a tabular format for each Polish Coal Company operating on the Polish market. The article was also present simplified: flow sheet of the steam and coking coal enrichment system. Based on the presented data, the planned needs and trends were described in terms of increasing production efficiency, minimizing water consumption and safety of work. A list of research and development works which must be undertaken were also presented as well as factors determining the technological development of the processing plants.

Studies on the quality of bituminous coal are mainly focused on physico-chemical analysis, examining the ash content, sulphur content, volatile matter content, moisture content, and the Net Calorific Value of coal. Until now, the above mentioned parameters form the basis of the Polish Standard PN-82/87002, on the basis of which individual types of bituminous coal are determined. In addition, an elemental analysis, providing information about the content of primary elements in the organic matter of solids, i.e. coal, hydrogen, nitrogen, oxygen, and sulphur, is carried out for the selected samples. This issue has been studied by many authors, which undoubtedly provide invaluable knowledge due to the huge amount of data, but, as the authors themselves indicate, the knowledge of the petrography of coal, coking properties (Probierz et al. 2012) and finally the coke obtained from individual coal types (based on tests carried out using the Karbotest installation or the so-called „box tests” performed in the coke oven battery) is still very limited. The article discusses the impact of petrographic composition on the quality of metallurgical coke. The analysis was performed using samples of coking coal from the following mines: Pniówek, Zofiówka, Borynia, and Krupiński. The mentioned coal types are used to produce coke mixtures used for the production of coke in the Przyjaźń and Radlin coking plants. Based on the rank of coal and physicochemical parameters, the mentioned coal types were classified according to the Polish classification and the UN/ECE International Classification of In-Seam Coals (UN/ECE 1995). The prediction of thermomechanical properties of coke (CSR and CRI) performed according to the original CCP method were compared with the results obtained using the classical method of Nippon Steel Corporation.

Over the past two years, coking coal prices have been the most volatile among major bulk commodities. On the supply side, the most important factor determining the movement of coal prices were weather problems affecting the exports of coal from Australia (Queensland), where the production of the best quality coking coals is concentrated. On the demand side, an important factor is the growing role of China on the market, which, being the world’s largest producer and consumer of metallurgical coal, has also become its largest importer. The dominant, about 75% share of China in the global spot market has resulted in their level of activity influencing the periodic price decreases or increases in international trade and prices based on CFR China (along with Australian FOB prices) have become important indicators to monitor market trends and determine levels of negotiated benchmarks. The exceptional volatility on the market led to a change in the quarterly price fixing mechanism for hard-load hard coal contractors in mid–2017 to apply a formula that assumes the valuation of their quarterly volumes based on the average of the basket of spot price indices. This reflects the broader trend of the evolving market, with growing spot market activity. The article describes the current situation on the international coking coal market and presents short-term forecasts for hard coking hard coal prices (PHCC LV), which are a reference point for fixing prices of other types of metallurgical coal (hard standard, semi-soft, PCI).

Over the past decade, the growing demand for imported coal from consumers (mainly Asian) coincided with supply constraints on the part of major suppliers. The sequence of events is referred to as force majeure. There were many events in the exporting countries, mainly including the cyclone and floods in Australia (Queensland, the world’s largest hard coking coal mining region). Imbalance between supply and demand causes commodity prices to be subject to cyclical changes, but in recent years the frequency and dynamics of these changes in the international metallurgical market (hard coking coal, semi-soft coking coal, PCI coal) has been extremely high. China, the world’s largest producer and consumer of coking coal, played a leading role in these events. Political action by the Chinese authorities regarding their domestic mining and metallurgical industries and the coke-chemical industry has made the country dethrone Japan since 2013 and has become a global leader in metallurgical coal imports. The rise of China’s importance in coal trading has become an important benchmark for monitoring market trends and benchmarking benchmarks. The market has become more bipolar and CFR China’s prices (in addition to Australia’s FOB prices). The paper describes the path of pricing mechanism changes in international trade contracts for metallurgical coal, against the background of market conditions that generate these changes.

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.

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.

The paper presents the correlation between the CRI (Coke Reactivity Index), CSR (Coke Strength after Reaction) and the remaining 36 quality parameters of coking coal from the Pniówek deposit (SW part of the USCB). The test results were obtained for a region of fundamental importance to the Polish reserves of coking coal, characterized by highly variable coalification and quality parameters. The tests related to the determination of relationships of the CRI and CSR indices to other parameters were based on 25 channel samples acquired from active workings. The characteristics of the variability of the CRI and CSR indices were analyzed using statistical methods. The dependencies between the CRI and CSR indices and the parameters having an impact on their values were determined using linear correlation. An attempt was also made to determine the correlations between the concerned parameters using the multiple correlation method. The obtained results have been presented and compared to the results of globally conducted experiments in the form of charts presented by (North et al. 2018b). No clear dependence of the CRI and CSR indices was exhibited in case of most of the analyzed quality parameters, which is supported by low correlation coefficients of r < 0.5. The statistical analysis exhibited only 9 cases of correlation between CRI and CSR with other quality parameters, where the correlation coefficient was r ≥ 0.5, that is: Ht a, Na2O, Al2O3 and SiO2, Mn3O4, da a and dr a. This confirms the different characteristics of coal from the studied area, exhibited multiple times, that should be related to the specific coalification process, especially the occurrence of thermal metamorphism.

Coke oven gas (COG) dome injection in COREX melter gasifier is recognized as one of effective method to reduce the amount of solid fuel used for gasification. In this work, a static model was developed to study the characteristics when COG is injected from dome. The critical bosh gas and critical fuel rate in COREX melter gasifier under different melting rate and coke rate were discussed. The amount of COG injection from dome under the critical fuel rates was studied. The results shows that when the heat of bosh gas reaching the critical value, the decrement of fuel rate decreases with the increase of melting rate and increases with the increase of coke rate. Under the critical fuel rate, the total volume of COG increases with the increase of melting rate and coke rate. After the COG injection, the amount and reduction capacity of the generator gas can meet the needs of reduction in shaft furnace. The findings of this work can be used as a theoretical basis to guide plant operations for COG injection.

The economic downturn in Europe and in the world, has affected the traditional branches of industry in a particular way. Development plans of domestic coke plants in terms of main production assets for the next years have been presented. Taking into account the current market situation, the coke plants strategy should aim at risk minimization through application of already known technologies. On the other hand, investments in scope of new and innovative technologies which are connected with a high level of variability, should be seen as an opportunity. Thus, evaluation of investment projects should be done in a different way than so far. The traditional discount analysis, because of its static nature, does not take into account variability and options included in projects with many decision moments - it can prove to be not sufficient. A tool which helps the decision makers in such situations, is the real options analysis. The article presents the findings of the research-development project on coal blend pre-drying implementation, realized by Zdzieszowice Coke Plant and ICHPW in Zabrze. The results achieved so far, as well as the concerns resulting from the project, have been discussed in this article. Further project development plans, aiming at the construction of a semi industrial research installation for analysing the impact of pre-drying on the coke making process have been presented. The article describes premises for the application of real options analysis as a tool to evaluate projects, the results of which are uncertain. The origin and structure of real options as well as the conditions of their application compared to traditional, discount based project evaluation methods, have been presented. The origin and characteristic parameters of real options have been discussed. In the next part, by applying the NPV and real options method, the research-development undertaking of coal blend pre-drying implementation on two coke batteries, has been evaluated. In order to assess the real option's value of the project, which is a classic European call option, the Black-Scholes formula has been used. The achieved results have been compared as well as the flexibility rate of the analyzed research-development project has been defined.