The closure of coal mines does not terminate their impact on the environment. Gas emissions into the atmosphere are the one of the problems. The closed ''Gliwice II'' shaft has been selected for a series of measurements to assess greenhouse gas emissions from the closed mine; however, only CO 2 emission has been detected. The article compromises obtained knowledge about the rate of emissions and the influence of meteorological parameters on this phenomenon-baric tendency, difference in dry-bulb temperature between flowing gas and the atmosphere (buoyancy effect) and wind speed. In the course of the conducted research, it was detected that the highest amount of carbon dioxide emission was V CO 2 = 0.023 m 3 /s (which is 82.8 m 3 /h) when baric tendency of pressure drop was 0.57 hPa/h, and the difference between dry-bulb temperatures gas and atmosphere was ?4.4°C (the highest difference in the obtained results). The rate of CO 2 emissions varied from 12.7 to 162.3 kg CO 2 =h. Carbon dioxide was detected up to 43 m from the shaft. The results can be considered as a general conclusion about gas behavior when it flows from the underground sites to the surface in natural conditions and about gas concentrations near a point of emission, especially in the case of former mines. However, it may also be useful for other applications, e.g., the leakages from installations of underground coal gasification, or gas drainage.
On the basis of three selected examples, some problems attributed to the presence of voids resulted from mining operations in already commissioned underground coal mines are discussed. Continuous and discontinuous deformations of the ground surface (sinkholes and subsidence troughs) of anthropogenic origination implicate hazards for the ground surface, even many decades after completion of mining work. Nowadays, when decommissioning and fl ooding of numerous mines happens, ground movements as well as seismic events related to fl ooding of abandoned underground mines can be observed. The fi rst case study draws attention to the problems of effective voids localisation methods as well as the reliability of grout injection operations for road construction purposes. The second case emphasizes a problem occurring often in areas with long and complex mining histories, meaning appropriate determination of origin, process and protective measures regarding occurred ground deformations, or damage to buildings. The third case describes specifi c effects on the surface (shocks and ground surface elevation) generated by the fl ooding of decommissioned mines.
Influence of surface modIfIcatIon on propertIes of staInless steel used for Implants WpłyW modyfikacji poWierzchni na WłaściWości stali nierdzeWnej stosoWanej na implantyThe aim of the study was assessment of the influence of stainless steel 316 LVM surface modification on its functional properties. The analyzed steel undergone a surface treatment consisting of the following processes: mechanical polishing, chemical passivation and deposition of Al2O3 layers by Atomic Layer Deposition method. The proposed variant of surface treatment will undoubtedly contribute to improving the functional properties of stainless steel intended for implants. In order to assess functional properties of the steel, electrochemical studies, adhesion (scratch test), wetting angle tests and topography of surface (AFM method) were performed. The obtained results of the study showed clearly that the proposed by the authors way of surface treatment including: mechanical polishing, chemical passivation and deposition of Al2O3 layer by means of the ALD method effectively improves the corrosion resistance of stainless steel.Keywords: ALD method, pitting corrosion, scratch test, wettability, AFM Celem pracy była ocena wpływu modyfikacji powierzchni stali nierdzewnej 316 LVM na jej właściwości funkcjonalne. Obróbka powierzchni składała się z następujących procesów: polerowanie mechaniczne, chemiczna pasywacja i naniesienie warstw Al2O3 metodą ALD (Atomic Layer Deposition). Zaroponowany wariant obróbki powierzchni niewątpliwie przyczyni się do poprawy właściwości funkcjonalnych stali przeznaczonej na implanty. W celu oceny właściwości funkcjonalnych stali przeprowadzono badania elektrochemiczne, badania adhezji warstw (scratch test), oraz badania zwilżalności (kąt zwilżania i badania topografii powierzchni metodą AFM). Uzyskane wyniki badań wykazały wyraźnie, że zaproponowany przez autorów sposób obróbki powierzchni, w tym: polerowanie mechaniczne, pasywacja chemiczna i naniesienie warstw Al2O3 metodą ALD skutecznie poprawia odporność na korozję stali nierdzewnej.
Abstract. For many years, the Salt Mine in Bochnia has conducted the extraction and restructuring of underground working to obtain new touristic routes. The works generate a large amount of rock salt material, colloquially called "salt debris", containing a large part of silty minerals. Due to the large concentration of NaCl which constitutes a threat to the environment, the salt debris may only be stored at hazardous material dumps. This is why the mine works towards the industrial use of the material. Currently, the debris is used to produce a stabilizing backfill mixture that is used for filling the liquidated "Moszczenica" shaft. The liquidation shall be completed in the beginning of 2018 and to continue the management of the salt debris, the mine plans to leach it in a newly constructed system and the saturated brine obtained in the process shall be introduced to underground workings. The paper presents the results of semi-industrial tests of leaching intensity of salt debris, depending on the graining and the time taken by the process. The tests were conducted for three grain classes of the salt debris (0-6, 0-10 and 0-20 mm), at a temperature of 15°C. The kinetic models of the process has been presented for the obtained results. The obtained results shall be used for the optimization of the operation of the future industrial system and shall be treated as input data for the automation control system.
Abstract. The injection of the colloidal suspensions of nano-iron (nZVI) into an aquifer is a novel method of removing metal ions from acidic water. In the batch tests, the equilibrium study of the sorption of metal ions, Cu(II) and Zn(II), on Green Tea nanoscale Zero-Valent Ion (GT-nZVI) was carried out. The sorption of metal ions on this reactive material was described using the Langmuir, Freundlich and Sips models. This last model described in a better way the sorption equilibrium in the tested range of concentrations and temperature. The value of determination coefficient (R 2 ) for the Sips model, for copper and zinc, was 0.9735 to 0.9995, respectively. GT-nZVI has very good properties in removing Cu(II) and Zn(II) from acidic water.The high values of qmaxS, the maximum adsorption capacity in the Sips model, amounting to 348.0 and 267.3 mg/g for Cu(II) and Zn(II), indicate the high adsorption capacity of GT-nZVI. The analyzed metals have good or very good affinity with GT-nZVI.
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