[en] In the last years interest in uranium recovery from secondary sources is growing. In Poland, the advanced studies are undertaken concerning the possibility of obtaining uranium from domestic resources and also secondary resources such as phosphate rocks and industrial wastes, including flotation tailings from the copper industry and phosphogypsum. There are two main reasons for these kind of studies: - recovery of heavy metals form the industrial wastes is important to the society, industry and environment; - the selective separation of uranium is a very important in the context of energy production and treatment of nuclear wastes. In the studies described the solid materials were leached with using either acid or alkaline solutions in stationary reactors or with percolative leaching. The obtained liquors were separated from solid residue and then were purified by liquid-liquid extraction or ion exchange chromatography. The studies were supported by the financial resources for science in the years 2017-2018 granted for the implementation of the international project co-financed 3643/IAEA/16/2017/0, IAEA Research Contract No: 18542. (author)

[en] Scarce uranium resources stimulate interest in U recovery from secondary resources as potential raw materials. Industrial wastes and by-products, and phosphate rocks were considered as a source of uranium in these studies. Two types of Polish industrial wastes: flotation tailings from the copper industry, phosphogypsum from the fertilizer industry and phosphate rocks from Morocco, Tunisia and Syria, used in POLICE phosphate fertilizers factory, were examined. Uranium, thorium and other metals were recovered using classical leaching methods (with acidic or alkaline solutions) and percolating leaching followed by solid-liquid separation. (author).

[en] Scarce uranium resources stimulate interest in U recovery from secondary resources as potential raw materials. Industrial wastes and by-products, and phosphate rocks were considered as a source of uranium in these studies. Two types of Polish industrial wastes: flotation tailings from the copper industry, phosphogypsum from the fertilizer industry and phosphate rocks from Morocco, Tunisia and Syria, used in POLICE phosphate fertilizers factory, were examined. Uranium, thorium and other metals were recovered using classical leaching methods (with acidic or alkaline solutions) and percolating leaching followed by solid-liquid separation. (authors)

[en] On January 28"t"h 2014 the Program of Polish Nuclear Energy was signed by Polish Government. According to this program Poland has to secure a constant supply of uranium for Polish NPPs in the future. Uranium in Poland occurs in Vistula Spit area in sandstone rocks and Podlasie Depression area in black dictyonema shales, which are low grade ores. Scarce uranium resources stimulate interest in its recovery from secondary resources as potential raw materials. Industrial wastes and by-products were considered as a source of uranium in this studies. Apart from uranium other valuable metals (e.g. vanadium, molybdenum or lanthanides) were recovered to improve the economy of the process. Three types of industrial wastes were examined: flotation tailings from the copper industry, phosphoric acid from the fertilizer industry and fracturing fluid from shale gas exploitation. Metals from flotation tailings were separated in two steps: 1) acidic leaching of the flotation waste using sulfuric acid solution and 2) separation of metals by ion-exchange chromatography. All the liquid samples were analyzed by ICP-MS method to determine the separation efficiency of the process. Uranium was recovered from phosphoric acid by high-pressure membrane filtration or by extraction/stripping integrated processes applying membrane modules Liquid-Cel® Extra-Flow (Celgard). Aqueous solutions after hydraulic fracturing are very diverse in terms of chemical composition, depending on borehole and fracturing technology applied. The content of various substances in backflow fluid depends on mechanical behavior and chemical composition of shale. Organic matter content in this type of waste did not exceed 1% usually, but the salinity is high. Initially, organic pollutants were removed and next the fluid was purified by combined various ion-exchangers. Individual metals were selectively eluted from ion-exchanger by combination of different eluents. The content of metals in samples was analyzed by ICP-OES. Organic matter was analyzed by TOC method. (author)

[en] Dense Medium (or Heavy Medium) Separation (DMS) is one of the most efficient and commonly used method of separation in different mining branches. Dense Medium for coal processing is based on the suspension of fine and dense material, usually magnetite or ferrosilicon, in water. Magnetite for that purpose is the most commonly used mineral in Polish mines, but has to be entirely imported from abroad. Ferrosilicon, recovered from Zinc-Lead waste could be an alternate to magnetite for use in DMS coal processing. In this study an attempt of recovering that material from “Miasteczko Śląskie” Zinc Plant wastes was made. By simple separation and comminution processes, large amount of magnetic fraction, which could be successfully used in dense medium as the substitution for the magnetite was obtained. Almost 70% of collected waste from lead refining process is proper for the use in the DMS process. Obtained fraction is relatively brittle and easy to grind, which should generate minor costs of production. Almost entire fraction is also highly reactive for magnetic field, which will be helpful in the recovery from dense medium solution, using existing magnetic separators in coal processing plants. Chemical analysis show that concentration of a few metals is significant, which may cause environmental obstacles. But that can also be solved, using simple method of recovery of metal ions from process water. (paper)

[en] Shale gas exploitation is the cause of many social protests. According to the protesters gas extraction technology threatens the environment: it consumes huge amounts of water, creates danger of poisoning drinking water, the formation of toxic wastewater, air contamination, noise, etc. Hydro-fracturing fluids could also leach radioactive isotopes e.g. uranium from the rock. The upper content of the main elements found in examined back flow fluids in Poland are the following: chlorine: 100.00 Kg/m"3, sodium: 40.00 kg/m"3, potassium: 0.90 kg/m"3, lithium: 0.15 kg/m"3, magnesium: 2.00 kg/m"3, calcium: 20.00 kg/m"3, strontium: 0.80 kg/m"3 and cesium: 0.06 kg/m"3 while the upper content of trace elements are the following: uranium: 3.5 g/m"3, lanthanum: 12.4 g/m"3, vanadium: 1.3 g/m"3, yttrium: 1.3 g/m"3, molybdenum: 2.0 g/m"3 and manganese: 9.7 g/m"3. The recovery of uranium, and other valuable metals, from back flow fluids will reduce an environmental impact of hydro-fracturing process. This poster details the treatment of back flow fluids in Poland allowing rare earth elements and uranium recovery

[en] This article presents the impact of MgB₂ wire bending and diameter on transport critical current density and irreversible magnetic field of a resultant coil. Unreacted MgB₂ wires 500 mm in length and 0.63 or 0.83 mm in diameter have been used in the fabrication of small diameter (14 mm) superconducting coils. The coils were subsequently annealed under isostatic pressure of 1 GPa for 15 min at 700 °C and 725 °C. Our results indicate that larger wire diameter, higher annealing temperature, and bending lead to slight reduction of critical current density and irreversible magnetic field in the coil.

[en] Recent results on powder-in-tube in situ Cu-sheathed MgB₂ wires have shown that copper powder additions to the core can accelerate the formation of MgB₂, increasing its volume fraction and greatly decreasing the amount of Mg–Cu intermetallic phases present in the core after heat treatment. The amount of added copper and heat treatment conditions strongly affect the critical current of the wire and require optimization. To identify the optimum parameters, eight wires with starting core compositions of Mg+2B+xCu with x = 0, 0.01, 0.03, 0.05, 0.07, 0.09, 0.12 and 0.15 were prepared with two heating ramp rates and their properties were investigated by SEM, XRD and J_c and n-value measurements. The highest J_c was found to be for x = 0.09, whereas x = 0.03 resulted in the highest n-value. The results are relatively independent of the heating ramp rate used for heat treatment. (paper)

[en] This article discusses the influence of MgB₂ wire diameter on critical parameters, dominant pinning mechanism, and n value. Studies were conducted on multifilament MgB₂ wires of the 0.84 mm and 0.64 mm diameter. The wires were annealed under 1 GPa isostatic pressure, between 650 and 730 °C. Studies show that the best results (J_c, B_irr, n value, and point pinning mechanism) for a 0.64-mm wire were obtained with annealing temperature of 650 °C. However, the best results for wires with a 0.84-mm diameter were obtained with annealing temperature of 730 °C. This research was conducted for exploring the use of MgB₂ wires in multi-section superconducting coils, e.g., main coils generating magnetic fields and compensation coils—increasing the homogeneity of the magnetic field. Our research indicates that the main coil made with larger diameter wires should be heated at higher temperature (730 °C). In contrast, compensating coils with smaller diameter wires should be heated at a lower temperature (650 °C).

No abstract available