1,383 research outputs found

    Geo-energetics of Ukrainian crystalline shield

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    Purpose. To develop an analytical method which allows investigating the energy condition of rocks within the Ukrainian Crystalline shield. Methodology. Analytical research on the energy condition of rocks has been conducted by means of a new method of research – the entropy one. The research on processes of redistribution of potential energy in the massif of rocks was conducted by analogy with an open thermodynamic system. The accepted methodological approach allowed investigating processes of energy exchange in rocks and natural transformations of some types of energy to others. Findings. The analysis is conducted and systematization of geodynamic conditions by underground mining of ore fields of Ukraine is executed. The ways of development of new hypotheses, theories and methods of research of the energy condition of rocks are given. The description perspective in world practice of a natural condition of rocks is enclosed. Components of redistribution of energy in the massif of rocks are defined: entropy, potential stresses and angles of their action. An inspection of the results obtained on convergence is conducted and corresponding conclusions on their application are drawn. Originality. The thermodynamic balance in rocks of the Ukrainian Crystalline shield is formed due to equilibration of vertical and horizontal power streams which, with increasing mining depth, enhance components of a tensor of stress on sedate dependence, rejecting them from hydrostatic ones during increasing in mining depth. Practical value. The entropy method of research which allows investigating natural state of rocks with increasing depth is developed. Classification of methods of research on the stress-strain state of rocks due to introduction of a synergetic group which includes entropy, thermodynamic and energy methods is improved. It is established that distribution of entropy in rocks of the Ukrainian Crystalline shield proceeds in mutually perpendicular directions, which correspond to vertical and horizontal energy streams

    Study of the kinetics of catalytic decomposition of hydrazine vapors on palladium

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    The decomposition rates of N2H4 on a palladium surface are studied. Experiments were conducted in a circulating unit at atmosphere pressure. The experimental method is described. The laws found for the reaction kinetics are explained by equations

    Method for calculation of drilling-and-blasting operations parameters for emulsion explosives

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    Purpose. Development of a new method for calculation of drilling-and-blasting operations parameters during underground mining with application of emulsion explosives taking into account their energy characteristics as well as physical and mechanical properties of rocks. Methods. The integrated methodological approach including analytical transformations of the received formulas for calculation of drilling-and-blasting operations parameters, their improvement and also computer modeling on the basis of a finite element method were used for the establishment of compression zones and formations of cracks in the massif around shots taking into account such energy characteristics of emulsion explosive as detonation velocity, explosion heat, density of the explosives, etc. Findings. The relative force coefficient was determined for the emulsion explosive of “Ukrainit” type taking into account the extent of detonation velocity realization, which allowed to calculate the necessary amount of explosives. On the basis of experimental data, consistent patterns of detonation velocity change depending on the charge density and diameter yielding to power law are determined for the emulsion explosive of “Ukrainit” type. Improvements have been made to the analytical expression determining the sizes of compression and fracturing zones around blast holes taking into account energy characteristics of the emulsion explosive of “Ukrainit” type as well as physical and mechanical properties of the blasted rocks. This allowed to develop a new algorithm of calculating parameters for drawing up the passport of drilling-and-blasting operations during underground mining. Originality. The method for calculating drilling-and-blasting operations parameters is based on the regularities of emulsion explosives energy characteristics change, the extent of detonation velocity realization as well as physical and mechanical properties of rocks. Practical implications. A new method has been developed for calculation of drilling-and-blasting operations parameters during mining with emulsion explosives application, which results in minimization of energy consumption for the mass breakage.Мета. Розробка нової методики розрахунку параметрів буропідривних робіт (БПР) при проведенні підземних гірничих виробок із використанням емульсійних вибухових речовин (ЕВР) з урахуванням їх енергетичних характеристик і фізико-механічних властивостей порід. Методика. У роботі використано комплексний методичний підхід, що включає аналітичні перетворення раніше отриманих формул розрахунку параметрів БПР та їх удосконалення, а також комп’ютерне моделювання на основі методу скінчених елементів зі встановлення зон зминання та утворення тріщин в масиві навколо шпурів з урахуванням енергетичних характеристик емульсійної вибухівки: швидкість детонації, теплота вибуху, щільність вибухових речовин (ВР) та ін. Результати. Визначено коефіцієнт відносної працездатності емульсійної вибухівки типу “Україніт” з урахуванням ступеня реалізації швидкості детонації, що дозволило визначити необхідну кількість ВР. На основі експериментальних даних встановлено закономірності зміни швидкості детонації від щільності та діаметру заряду для ЕВР типу “Україніт”, які змінюються за ступеневим законом. Удосконалено аналітичний вираз, що визначає розміри зон зминання та тріщин, які утворюються навколо шпурів з урахуванням енерге- тичних характеристик ЕВР “Україніт” і фізико-механічних властивостей порід, на чому ґрунтується подальший вдосконалений алгоритм розрахунку параметрів для складання паспорта БПР при проведенні підземних гірничих виробок. Наукова новизна. Полягає у використанні закономірностей зміни енергетичних властивостей ЕВР, ступеня реалізації швидкості детонації та фізико-механічних властивостей гірських порід при розробці методики розрахунку параметрів БПР. Практична значимість. Розроблено нову методику розрахунку параметрів БПР при проведенні гірничих виробок на основі використання ЕВР, що забезпечує мінімізацію енергетичних витрат на руйнування масиву.Цель. Разработка новой методики расчета параметров буровзрывных работ (БВР) при проведении подземных горных выработок с использованием эмульсионных взрывчатых веществ (ЭВВ) с учетом их энергетических характеристик и физико-механических свойств пород. Методика. В работе использован комплексный методический подход, включающий аналитические преобразования ранее полученных формул расчета параметров БВР и их усовершенствование, а также компьютерное моделирование на основе метода конечных элементов по установлению зон смятия и образования трещин в массиве вокруг шпуров с учетом энергетических характеристик ЭВВ: скорость детонации, теплота взрыва, плотность взрывчатых веществ (ВВ) и др. Результаты. Определен коэффициент относительной работоспособности ЭВВ типа “Украинит” с учетом степени реализации скорости детонации, что позволило определить необходимое количество ВВ. На основе экспериментальных данных установлены закономерности изменения скорости детонации от плотности и диаметра заряда для ЭВВ типа “Украинит”, которые изменяются по степенному закону. Усовершенствовано аналитическое выражение, определяющее размеры зон смятия и трещинообразования, образуемых вокруг шпуров с учетом энергетических характеристик ЭВВ “Украинит” и физико-механических свойств взрываемых пород, на чем основывается дальнейший усовершенствованный алгоритм расчета параметров для составления паспорта БВР при проведении подземных горных выработок. Научная новизна. Состоит в использовании закономерностей изменения энергетических характеристик ЭВВ, степени реализации скорости детонации и физико-механических свойств горных пород при разработке методики расчета параметров БВР. Практическая значимость. Разработана новая методика расчета параметров БВР при проведении горных выработок на основе использования ЭВВ, обеспечивающая минимизацию энергетических затрат на разрушение массива.The authors express their deepest gratitude to V.P. Kuprin, Doctor of Philosophy in Chemistry, Professor, State Prize Laureate of Ukraine in Science and Technology for providing research base and organizational support during industrial experiments

    Development of natural underground ore mining technologies in energy distributed massifs

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    The object of research is the technology and facilities for underground mining of ores in the disrupted massifs. One of the most problematic places is the formation of man-made voids; which influence the occurrence and redistribution of stress-strain state (SSS) of the rock massif. Their existence in the earth's crust provokes the influence of geomechanical and seismic phenomena; up to the level of earthquakes. The study used: – data from literature sources and patent documentation in the field of technologies and facilities for underground mining of ores in the energy-disrupted massifs of substantiation of technological parameters of operating units; – laboratory and production experiments; – physical modeling and selection of compositions of solidifying mixtures. Analytical researches; comparative analysis of theoretical and practical results by standard and new methods with the participation of the authors were performed. The questions of seismogeodynamic monitoring of the SSS of the rock massif during the safe development of rock-type ore deposits are considered. The interaction of natural and man-made systems providing geomechanical balance of ore-bearing massifs is shown. Possibilities of controlling the geomechanics of a massif with filling of man-made voids with various solid mixtures and tails of underground leaching of metals from substandard ores are investigated. The typification of processes is given and the distinctive features of underground block leaching of metals from rock ores are formulated in the aspect of controlling the geodynamics of the massif. The principle estimation of the combined technologies with rationalization of use of the SSS of the rock massif for regulation of the sign and magnitude of stresses in natural and artificial conditions is shown. The conclusions about the effectiveness of the controlled interaction of natural and man-made systems; ensuring the geomechanical balance of massifs and the earth's surface in the area of subsoil development over a long period of time. The research results can be used in the underground development of ore deposits of complex structure of Ukraine; the Russian Federation; the Republic of Kazakhstan and other developed mining countries of the world

    Development of principles of opening strength during underground mining

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    There have been analyzed fundament a land applied research work saimed at development, testing and manufacturing application of efficient technological plans for developing, supporting and maintaining underground workings. There has been found the evolution of scientific and production principles which underlie the technologies of supporting and maintaining underground workings. The analyzed ones have been evaluated. There have been found trends of principle development ranging from counteraction and counterbalance to contribution, removal and transfer of the high pressure energy concentrated aroundworkings
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