The article describes the method of controlling the recovered grade based on measuring the intensity of volume ultrasonic oscillations and Lamb waves covering a fixed distance through the test medium and on a metal plate contacting the test medium at various time points of deliberate motion of ground materials.

The authors suggest a method of determining density of ground ore particles in the pulp periodically after isolating the pulp flow in the vertical part of the measuring vessel based on measuring attenuation change values in Lamb waves covering a fixed distance on a plate contacting the medium under study and high frequency volume ultrasonic oscillations that have come through it within a certain time period.

There are given dependencies of amplitudes of measuring channels based on volume ultrasonic oscillations and surface Lamb waves, size distribution according to solid phase pulp particles for various types of ores under study, a set of curves for determining the recovered grade with regard to various types of ores under study.

In early 2021, over 5 million European Union (EU) citizens had applied for settled status to secure their right to continue to live, work and study in the United Kingdom (UK) after the country’s withdrawal from the EU (Brexit). In 2018, the Home Office launched a Statement of Intent to implement an application process for EU citizens through its EU Settlement Scheme. In the period leading up to Brexit, the UK gov-ernment assured EU migrants that their existing rights under EU law would remain essentially un-changed and that applying for settled status would be smooth, transparent and simple. However, the application process has resulted in some long-term residents failing to obtain settled status, despite providing the required information. Based on qualitative in-depth interviews with 20 EU migrants living in two major metropolitan areas in Northern England, this article discusses the significant barriers which EU citizens face in the application process. This situation particularly affects the most vulnerable EU mi-grants with limited English-language skills and/or low literacy levels as well as those who are digitally excluded. The study contributes to the growing body of research on the consequences of Brexit for vulner-able EU migrants in the UK, focusing specifically on Central and Eastern European migrants.

The process of enrichment in a jig has usually been described and analysed using particle density as a separation feature. However, a degree of particle loosening in the jig bed is affected by, inter alia, the terminal particle free settling velocity which in turn is affected by the size, density and shape of a particle. Therefore, the terminal particle settling velocity clearly characterises the feed transferred to a jig for the enrichment process. Taking the comprehensive particle geometric (particle size and shape) and physical properties (particle density) into account comes down to the calculation of the terminal particle settling velocity. The terminal particle settling velocity is therefore a complex separation feature which comprises three basic particle features (particle density, size and shape). This paper compares the effects of enrichment of coal fines in a jig, for two cases: when the commonly applied particle density is separation feature and for the particle settling velocity. Particle settling velocities were calculated in the selected three particle size fractions: –3.15+2.00, –10.00+8.00 and –20.00+16.00 mm based on the industrial testing of a jig for coal fines and detailed laboratory tests consisting in determining particle density, projective diameter and volume and dynamic particle shape coefficient. The calculated and drawn partition curves for two variants, i.e. when particle density and particle settling velocity were taken into account as the separation argument in selected particle size fractions, allowed to calculate and compare separation precision indicator. With the use of a statistical test, the assumption on the independence of random variables of the distribution of components included in the distribution of the particle settling velocity as a separation feature during enrichment in a jig was verified.

In area of zinc and lead exploration the most common elements of landscape are mine spoil-heaps and also dumps and settling tanks connected with zinc and lead metallurgy and ore flotation. They are located in the northern part of Katowice Province, on a line Piekary - Bytom - Bukowno - Olkusz and cover area of about 350 hectares. The individual settling tank in this area is between 15 and 40 hectares and considerably deforming landscape. A fine-grained dolomite is main material of tank sediments. The sediment contains maximally up Io 8.0% of Zn, 1.5% of Pb and Cd in content usually over 100 mg/kg. In spite of high salinity and high Zn, Pb and Cd content the settling tanks can be soil-less reclamated but the first stage of the reclamation should be trying to stop weathering and erosion processes. For the soil-less reclamation so

Sedimentation tanks have a vital role in the overall efficiency of solid particles removal in treatment units. Therefore, an in-depth study these tanks is necessary to ensure high quality of water and increasing the system efficiency. In this work, an experimental rectangular sedimentation tank has been operated with and without a baffle to investigate the system behaviour and effectiveness for the reduction of solid particles. Turbid water was prepared using clay, which was collected from the water treatment plant of Al Maqal Port (Iraq), mixed with clear water in a plastic supply tank. Raw and outflow samples were tested against turbidity after plotting a calibration curve between inflow suspended solids versus their corresponding turbidity values. The key objective was to assess the impact of different flow rates, particle concentrations, heights and positions of the baffle on the system efficiency. Findings showed that the tank performance was enhanced significantly (p < 0.05) with the use of a baffle placed at a distance of 0.15 of tank length with height equal to 0.2 of tank depth. Higher removal efficiency (91%) was recorded at a lower flow rate (0.015 dm3∙s–1) and higher concentration (1250 mg∙dm–3), as the treatment efficiency enhanced by 34% compared with the operation without a baffle. Placing the baffle in the middle of the sedimentation tank produced the worst results. System efficiency for solids removal reduced with increasing baffle height. Further research is required to evaluate the efficiency of an inclined baffle.

At the National Institute of Metrological Research (INRIM) an evaluation of a commercial dual source high resistance bridge has been performed. Its two main measurement modes (single measurements and multiple measurements) have been investigated. The best settle time of a 10:1 measurement of high resistance ratio has been estimated to be about three times the time constant of the circuit involving the resistors. This constant, in turn, depends on the highest value resistor. By means of mathematical estimators, suitable numbers of the readings of the detector have been established in order to minimize noises. A compatibility test at 100 TΩ has shown that the best precision of the commercial bridge is achieved utilizing the multiple measurements mode with the auto update function. This mode also allows the characterization of a resistor as a function of the settle time. This characterization can be useful for the owner of the resistor who can request the laboratory to perform the calibration of the resistor with the settle time which is necessary for him.