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Abstrakt

The article discusses the validation process of a certain method of balancing gas contained in the pore space of rocks. The validation was based upon juxtaposition of the examination of rocks’ porosity and the effects of comminution in terms of assessing the possibility of opening the pore space. The tests were carried out for six dolomite samples taken from different areas of the ‘Polkowice-Sieroszowice’ copper mine in Poland. Prior to the grinding process, the rocks’ porosity fell in the range of 0.3-14.8%, while the volume of the open pores was included in the 0.01-0.06 cm3/g range. The grinding process was performed using an original device – the GPR analyzer. The SEM analysis revealed pores of various size and shape on the surface of the rock cores, while at the same time demonstrating lack of pores following the grinding process. The grain size distribution curves were compared with the cumulative pore volume curves of the cores before grinding. In order to confirm the argument put forward in this paper – i.e. that comminution of a rock to grains of a size comparable with the size of the rock’s pores results in the release of gas contained in the pore space – the amount of gas released as a result of the comminution process was studied. The results of gas balancing demonstrated that the pore space of the investigated dolomites was filled with gas in amounts from 3.19 cm3/kg to 45.86 cm3/kg. The obtained results of the rock material comminution to grains comparable – in terms of size – to the size of the pores of investigated rocks, along with asserting the presence of gas in the pore space of the studied dolomites, were regarded as a proof that the method of balancing gas in rocks via rock comminution is correct.

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Autorzy i Afiliacje

Mateusz Kudasik
Anna Pajdak
ORCID: ORCID
Norbert Skoczylas
ORCID: ORCID

Abstrakt

The separation or beneficiation processes are conducted in many devices and concern many various types of minerals and raw materials. The aim of conducting these processes is always to achieve the best possible results allowing as much of the useful component as possible to be obtained by maintaining reasonable costs of the process. Therefore, it is important to have the possibility to monitor the process effects and to have efficient tools to evaluate the course of it. Generally, the ore’s ability to partition into concentrate and tailings is called its efficiency, upgradeability etc. It can be said that there is no unambiguous measure of upgradeability and there are many factors in use which enable to evaluate it qualitatively. Among them are such commonly known parameters as: recovery, losses, yield, upgrading ratio and many others. They are based on three principal parameters that is the average content of the useful component α, the contents of this component in concentrate β and the contents of this component in tailings ϑ. For a given ore (assuming that α = constant), the multi-product separation results can be treated as points of a trajectory located on the surface of factor w in a three dimensional space (β, ϑ, w). The course of the trajectory depends on the ore petrographic and mineralogical properties preparation for the process. For these reasons, searching for optimal (potential) possibilities of the ore is relative, which is presented in the example of Halbich, Fuerstenau and Madej upgrading curves. Such curves are efficient tools to evaluate the course of a separation (beneficiation) process and each of their types allow the effects to be shown in different perspective. Apart from this, they allow also the optimal feed conditions to conduct a certain process with aim of achieving the expected results to be found. Furthermore, the effect of the ore preparation on the flotation results, on the sum of recoveries of the useful component in concentrate and residual recovery in tailings is presented in the paper. The results indicated that any additional contamination of concentrate should be taken into account during the organization of the flotation process. In this way, the results of fractionated flotation have much valuable information to establish the course of the process.
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Autorzy i Afiliacje

Dariusz Foszcz
Tomasz Niedoba
Tadeusz Tumidajski

Abstrakt

The article concerns investigations over benefits of application of HRC devices into sulphide copper ore processing plant. High pressure comminution appears to be very effective technology in hard ore processing circuits, especially in terms of energy consumption. This can be particularly observed in downstream grinding and beneficiation operations. A series of pilot-scale crushing tests in HRC roller press for various levels of operating pressure, were performed. HRC crushing effectiveness along with downstream grinding process course for each crushing product were also under analysis. The investigations were supplemented by analysis of flotation process effectiveness and impact of the process of high-pressure comminution on environment (dust emission). The results of investigation show that operating pressure level influences the obtained comminution results (comminution degree, yield of finest particle size fractions). The grinding effectiveness, measured through production of the finest particle size fractions was significantly influenced by the operating pressure. The results show that higher values of operating pressure (4.0 and 4.5 N/mm2) are not as efficient within this scope as the pressure 3.5 N/mm2. Dust emission is also correlated with the operating pressure value.
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Autorzy i Afiliacje

Daniel Saramak
Tomasz Gawenda
Agnieszka Saramak
Dariusz Foszcz
Zdzisław Naziemiec

Abstrakt

W artykule opisano wykształcenie litologiczno-facjalne skał złożowych w strefach elewacji stropu białego spągowca oraz relacje między litologią a intensywnością okruszcowania Cu-Ag. Szczególny nacisk położono na charakter enklaw pozbawionych mineralizacji bilansowej (stref bezzłożowych) wewnątrz bryły złożowej. Za strefy bezzłożowe uznaje się przestrzenie, w których mineralizacja siarczkami Cu zazwyczaj występuje, jednak jej ilość nie spełnia kryterium brzeżnego dotyczącego zawartości Cu w kopalinie. Dla zilustrowania zmienności parametrów złożowych ściśle związanych z uwarunkowaniami facjalno-litologicznymi skał goszczących, na podstawie obserwacji terenowych i wyników opróbowania złoża wykonano metodami geostatystycznymi trójwymiarowe modele litologiczne i geochemiczne dla dwóch obszarów badań. Obszary badań obejmują fragmenty Północnej Elewacji Rudnej wraz z otaczającymi elewację depresjami w granicach złóż Sieroszowice i Rudna. Dzięki przekrojom przez modele 3D scharakteryzowano wykształcenie złoża w obszarach elewacji stropu utworów piaskowcowych, gdzie profil litologiczny określany jest jako „nietypowy” z powodu braku serii łupków miedzionośnych, czyli warstwy najbardziej charakterystycznej dla złóż rud miedzi na monoklinie przedsudeckiej. Potwierdzono dużą zmienność kształtu bryły złożowej oraz nieregularność granic stref mineralizacji bilansowej i enklaw skały płonnej w złożu. Stwierdzono obecność wielkoobszarowych enklaw skały płonnej w całym profilu skał dolnego cechsztynu (obszary pozbawione bilansowego okruszcowania miedziowego) i niewielkich stref płonnych piaskowców wzbogaconych w spoiwa anhydrytowe w sąsiedztwie bloków złoża bilansowego ulokowanego w piaskowcach ilastych. Wskazano na możliwość występowania w obrębie złoża bilansowego płatów skał płonnych w stropowej warstwie białego spągowca, bezpośrednio przy granicy z dolomitem wapnistym i nieregularnych przerostów skał płonnych wewnątrz utworów piaskowcowych. Ponadto zaobserwowano niewielkie strefy silnego wzbogacenia w siarczki Cu w strefach kontaktu spoiw siarczanowych i ilastych w serii piaskowcowej białego spągowca.

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Autorzy i Afiliacje

Wojciech Kaczmarek
Mariusz Dudek
Katarzyna Golda
Monika Wasilewska-Błaszczyk

Abstrakt

Landslide is a common geological disaster which causes huge losses to people’s properties and national economic development. How to prevent and control landslides has become an important issue. This article introduces the geological and geographical environment of the landslide body, analyzes the basic characteristics of the landslide, calculates the landslide stability based on the ultimate equilibrium theory-based transfer coefficient method, discusses the development trend of the landslide and comes up with corresponding control schemes by taking the landslide body of Black Bovine Cave Copper Ore Mining & Beneficiation Project as example. It is found that the control scheme – “anti-slide pile + retraining wall + baffle + anchor cable” can be used to effectively prevent and control the geological disaster according to calculation. The study results can provide a reference for landslide body control.
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Autorzy i Afiliacje

Hanhui Wu
1
ORCID: ORCID

  1. Civil Engineering, School of Civil Engineering, Chongqing Chemical Industry Vocational College, 400020 Chongqing, China

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