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This paper presents the development and experimental validation of an intelligent variable-structure control system for optimizing industrial ventilation in ATEX (ATmospheres EXplosibles) environments. Current ventilation solutions, based on continuous maximum-flow operation, consume 15 to 40 percent of total industrial hall energy and remain largely reactive to hazardous atmosphere formation. The proposed system integrates Model Predictive Control (MPC) with Artificial Neural Network (ANN) algorithms and a spatia...

The monitoring of open-pit slope stability is critical for safety, economic, and environmental reasons. The comprehensive approach to monitoring has been analyzed, addressing safety, economic, technological, ecological, legislative, and social responsibility aspects, ultimately contributing to sustainable mining practices. Various methods and technologies for monitoring slope stability have been determined as essential. Visual inspections are useful, but they depend on the qualifications of the observer and may ov...

The paper presents the results of investigation of the process of leaching of scandium from chloride wastes generated in titanium production to optimize the parameters of extraction into solution. The effects of key factors, including solid-to-liquid ratio (S:L), hydrochloric acid (HCl) concentration, process duration, stirring speed and the influence of temperature on the degree of scandium extraction into solution were studied. Experimental results indicate that optimal conditions for maximum extraction are: S:L...

In this study, the extraction efficiency of rhenium ions in the form of perrhenate (ReO4?) from model aqueous solutions was investigated using a binary ion-exchange system based on KU-2-8 (strongly acidic cation-exchange resin) and AV-17-8 (strongly basic anion-exchange resin). The ion exchangers were separately weighed and combined in varying molar ratios (6:0, 5:1, 4:2, 3:3, 2:4, 1:5, and 0:6), and were immobilized within a chemically resistant polypropylene mesh bag to maintain phase separation while allowing s...

The growing demand for refractory rare metals, such as niobium, necessitates the development of efficient extraction methods from alternative sources, including industrial waste from metallurgical plants enriched with niobium and zirconium. This study investigates the solvent extraction of niobium from a fluoride-sulfuric acid solution obtained by leaching rare-metal-containing waste from titanium-magnesium production. The efficiency of niobium recovery using a trialkyl phosphine oxide-based extractant (Cyanex 923...

The processing of titanium-zirconium concentrates with high chromium content presents a significant challenge due to the inhibitory effect of chromium on industrial applications. This study investigates the composition of titanium-containing concentrate from the Obukhovskoye deposit using X-ray diffraction (XRD), X-ray fluorescence (XRF), and thermogravimetric analysis. The findings indicate that chromium is uniformly distributed in both magnetic and non-magnetic fractions, complicating its selective removal by co...

As part of the experimental studies carried out in the Department of Civil, Environmental Engineering and Architecture of the University of Cagliari, to identify the best techniques for recovering of combustible materials, contained in the waste resulting from the dismantling of the anodes of spent electrolytic cells used in the production of primary aluminium, to be concentrated by flotation, work was first carried out to reduce the size of the waste, in order to give it a particle size that would allow it to be ...

This paper presents the results of laboratory processing tests conducted to explore the potential for beneficiation of a wollastonite mineral (calcium metasilicate, CaSiO3). The ore studied comes from a mineralized body located in the southern part of Sardinia (Italy), which has been studied in the past with geological surveys and sampling. In the investigated area the mineralization was very irregular. The encasing rocks consist of schist and the mineralized body is composed of wollastonite associated with limest...

Austempered Ductile Iron (ADI) is a promising material whose structure is obtained by isothermal processing, i.e. isothermal decomposition of austenite in the bainitic range. It is used in various industrial fields. It is characterized by an excellent combination of tensile strength and ductility, exceeding the properties of quenched and tempered steels in the strength range of 800 - 1500 MPa. Its production is problematic because the ferritic or ferritic-pearlitic ductile iron (SGI), which is the basis for the pr...

Oilfield brine extracted with hydrocarbons is often considered as a problematic waste. The typical management option for this produced water is reinjection into the formation to maintain the reservoir pressure (or just for disposal). High salinity of produced water is on the one hand a drawback, but on the other hand an advantage because it can be used as a raw material for the production of valuable chemicals. In this paper a freezing-thawing desalination method was tested to obtain partially desalted water and c...