Angel Zabchev, Romeo Alexandrov ABSTRACT. The AZUR apparatus is intended to control the insulating resistance in mine networks with an isolated star centre. The indication of the measured insulating resistance is realised by a pointer meter with a reversed nonlinear scale, which makes it difficult to read. The methodology for the development of an analogue converter ...

Danail Terziyski, Dimitar Kaykov ABSTRACT. Modern mining practices rely to a great extent on the application of numerical methods for establishing design alternatives, leading to significant economic benefits. In the current article mine haul road design and construction are treated as two interconnected problems – 1) selection of a suitable optimisation for haul road design and ...

Veneta Stefanova, Petar Petrov ABSTRACT. Sustainable land application in post-mining areas is an essential ecological issue, connected with disturbed areas, pollution of heavy metals, etc. The current research studies opportunities for phytoremediation of lands disturbed by copper mining. Environmental state and soil conditions are examined. Analyses show that soils are weakly acidic, with a low concentration ...

Siilegmaa Sereenen, Oyuntugs Magsar, Terry O’Neill ABSTRACT. Energy independence is one of the most important issues for almost every country and the world. Mongolia strives to have various types of energy sources and reduce energy dependence. Energy dependence always influences economic dependence of any country. Utilising its own country’s resources is optimal to reduce energy dependence. ...

Vessela Petrova ABSTRACT. Circular economy is a key instrument for reducing climate change and transition to green economy. The industrial symbiosis is a circular business model – a concept, discussed as a platform for exchange of materials among business companies in order to achieve sustainability and reduce waste. “Shared use” of wastes as raw-materials results in ...

Cyril T. O’Connor, Kirsten C. Corin ABSTRACT. It has been shown that the partial molar excess Gibbs energy (G̅ex) can be used as an indicator of hydrophobicity and hence contributes to explaining the behaviour of collectors in the recovery of minerals by flotation. This is because hydrophobicity of a mineral particle on which a collector is ...

Nikolaos Koukoulis, Georgios N. Anastassakis ABSTRACT. The current paper deals with the re-processing of mineralised mine waste from magnesite processing operations aiming at the recovery of the value. Two cases of mineralised waste were examined. First, waste derived from the removal of “fine” before hand-sorting, with particle size of -40 mm; this waste is usually stockpiled, ...

Gospodinka Gicheva, Alexander Chanachev, Sergei A. Kulinich ABSTRACT. Nowadays, mining industry is striving to be regarded as a modern and highly-technological field with no negative connotation to its name. The human factor is constantly increasing in significance, making mining industry more people oriented, and more and more efforts are being made to bring modern technologies into ...

Plamen Georgiev, Marina Nicolova, Maria Filipa Ivanova, Irena Spasova, Stoyan Groudev ABSTRACT. The study aimed to determine the effect of the acid mine drainages` flow rate on the iron adsorption by ion-exchange resin LEWATIT MonoPlus TP 207 in a fixed-bed column and to evaluate which widely used models describe that process better. The ferrous iron was ...

Nicolae Daniel Fîță, Sorin Mihai Radu, Roland Iosif Moraru, Mila Ilieva Obretenova ABSTRACT. Until recently, the European Union’s energy policy was against coal for pollution reasons, but with the start of the military war between Russia and Ukraine, coal has become one of the energy resources to reconsider. The lack or depletion of oil and natural ...

Naci Duru ABSTRACT. Increasing complexity of ore deposits requires operations to be continuously improving their cost competitiveness. Mathematical modelling and process simulation techniques are useful tools to understand the process, define bottlenecks and increase process efficiencies. This paper presents a crushing and grinding circuit of a chromite ore gravity separation plant’ simulation model results and actual ...

Alexander Brodt ABSTRACT. A method for direct liquefaction of coal is presented. After separating the coal from waste rock gravitationally in an aqueous salt solution, drying and grinding, the purified separated coal is mixed with a paste-forming reagent. The paste is ground until a colloidal particle size and hydrogenated for 2 hours at temperature of 405°C ...

Diana-Maria Banu, Ana-Maria Obreja, Ioana-Carmen Popescu*, Sorin O. Mihai ABSTRACT. Anthropogenic radioactive pollution of the environment resulting from the research and exploitation of uranium resources is a topical issue for the scientific community because it represents a threat to people’s health conditions and has a highly negative impact on the environment. The sources of radioactive pollution ...

Velichka Arahangelova, Alexandre Loukanov ABSTRACT. The copper is the second largest strategic raw material. Since there is a huge gap between copper production and consumption, a green and eco-sustainable recycling technology is necessary that is able to process the copper from secondary sources of waste and scraps. Here we demonstrate the photo-oxidising properties of pyrrolic nitrogen-dominated ...

Todor Angelov ABSTRACT. A composite flotation tailings sample from historic Medet tailings dam was characterised to understand occurrences of copper and hydraulic properties of the material and to determine if there is an economic benefit of its reprocessing using hydrometallurgical processes. Conventional ICP-OES multi-element scan and carbon and sulphur determination by Leco were followed by sequential ...