DonNTU   Masters' portal

Abstract

Important note: When writing this abstract the work is not yet completed. The planned completion: December 2013. January 2013. The full text of work and materials on the topic can be obtained from the author or a supervisor after defense of the thesis master's degree

Contents

Introduction

The development of the coal industry of Ukraine, as the basis of national energy independence is impossible without solution of actual problems in the field of labour protection. Alarming is the statistics on occupational diseases miners caused by the mining dust, as well as the consequences of sudden explosions пылеметановых mixtures. According to the State McNeil on safety of works in a mining industry of Ukraine annually brings economic losses from the stated reasons for the sum of about 1.5 billion hryvnias.

1. Theme urgency

In the conditions of coal mines the main sources of dust are the processes of cleaning and tunneling works, transportation of mountain weight, etc. In the production processes of the mine surface complex air pollution обусловленна mainly emissions of the main ventilator installation and thermal engineering facilities of the mine. As a result of this, a so-called dust cap. Therefore, the study of mechanisms of formation and regularities of the negative manifestations of mine anthropogenic dust cap is an important scientific problem, as during the change people are constantly exposed to and the harmful effects of aerosol mining dust as in underground conditions, as well and on the whole territory of the surface of the complex.

Analysis of scientific research and technical solutions aimed at the protection of workers from the mining dust in the conditions of coal mines showed, that the main way to deal with the dust is water capture dust (irrigation), i.e. the capture and sedimentation of solid particles of a dust drops of liquid. Along with certain progress achieved in the implementation of this method of control, remains unresolved is an important scientific task, which consists in the necessity of the disclosure mechanisms and laws that allow to enhance its effectiveness, in particular, impulsively-wave influence of liquid drops in the dust particles to activate processes water capture dust. At that, in the literature there are no data about the decision of the important theoretical issues in the study of possibilities of use of dispersed turbulent flow «gas - liquid droplets and solid particles of dust» to increase the efficiency water capture dust. The analysis of well-known research shows that the tasks of increasing the efficiency dedusting air droplet should be tackled in an integrated manner, on the basis of the use of the hydrodynamic, in particular, impulsively - wave and thermodynamic effects, for example, with the use of reduced air (nitrogen) in the processes of irrigation and water capture dust.

The relevance of these tasks, their scientific - technical and social importance of the concentrated into a single problem, which need to uncover the mechanisms and regularities of the dangerous manifestations of the dust in the conditions of coal mines. It is also necessary scientifically substantiate the possibility of the forecast of extreme dust States with a view to their prevention, and the gallery develop scientific bases of a method that allows to improve the means to improve the water capture dust by means of the pulse-wave effects, which will improve the operating conditions of work of miners at the dust factor and reduce the level of occupational diseases.[3]

Since questions of dust control relevant to many of the countries, then they are studied not only by the domestic scientists. In this work were considered methods of dust suppression of Ukraine, England, Germany, Russia.

2. Goal and tasks of the research

The aim of the research is the study of the long-applied and innovative ways of dealing with the dust and improving them.

Main tasks of the research:

  1. The integrated application of various ways to prevent and reduce the generation of dust.
  2. Analysis of the existing methods and equipment for dust suppression.
  3. Assessment of the effectiveness of the application of ways and means.
  4. The search for and identification of the shortcomings of the existing means and methods of struggle with dust in mines.
  5. The development of alternative options for dust control.
  6. Dedusting between mine air with the use of new technologies for the reduction of occupational morbidity of the miners in the conditions of Novodzerzhinskaya mine

Research object: coal dust.

3. Review of research and development

The complex dedusting of the mine air is implemented through three, to a certain extent interrelated areas: the reduction of dust, reducing release of dust (transition dust generation in suspended state) and cleaning of air from dust enclosed.

The humidification of coal contributes to the growth of adhesion forces between surfaces of dust particles and the formation of these large units, quickly check of air masses under the action of gravity. It is established, that the increase of humidity of coal by 1-3 % leads to decrease of dust formation at 75-80 %. At a relative humidity of coal more than 12 % of dust formation is practically absent.

For improving wettability of coal in the preliminary his wet the applied surface-active substance (SAS). Surfactant molecules are adsorbed on the surface of the liquid films and thereby reduce the surface tension of water and increase moisten ability of its due to the adsorption of the surfactant molecules on the surface of the particles of a dust.

In addition to pre-wetting of the coal seam, in longwall faces apply measures for dust suppression and dedusting air by means of irrigation.

The essence of the dust suppression of irrigation lies in the fact that during the interaction of drops of a liquid with a particle of dust occurs her wetting, the seizure of straw and deposition of the resulting machine - dust particle - water.

For dedusting of ventilation flows of the greatest application have found the veil: water, water air, with water air ejectors.

Effective dust control, including at the same time the cleaning of dusty air and irrigation of the mountain mass of water is achieved with the use of cylindrical and conical water air ejectors. The principle of operation water air ejector (Image 1) consists in the fact, that due to the low pressure created by water torch nozzle, hoovered dusty air, forming with dispersed water mixture, which, in turn, is sent for dust suppression. Water air ejectors are used, in particular, for dust control when shifting sections mechanized roof supports.

Image 1 - Water air ejector

1 - nozzle; 2 - water; 3 - dusty air; 4 - mixture.

On the principle of ejector is also based dust control at the loading points and unloading of coal through irrigation him under the shelter with a cone nozzles.

For dedusting of the air stream, outgoing from the coal face in the mines, where there is swelling of the wall rocks, apply mist formation of the veil with the reduced consumption of the liquid. The fluid flow rate for the fogging of the veil - 0, 05л per 1m3 passing air at a pressure of 0,3-0,4 MPa.

The veil for dedusting air flow installed at a distance of not more than 20m away from the window of a lava on a direction of movement of the air.

Irrigators the fogging of the veil is installed so the cross-section of production was completely blocked torches sprayed liquid, as shown in the animation.

Animation 1. — Cleaning ventilate torrents from dust water screens

3.1 Overview of domestic methods of struggle with dust

As a domestic way of dust suppression was reviewed by the way, suggested by the Professor of Donetsk national technical University Gogo V.B. They investigated the problem of improvement of conditions of work of miners at the dust factor. Developed the theory of the hydrodynamic dedusting on the basis of pulse-wave effects, which arise in the process of absorption of particles of a dust drops of liquid. Justified rational technical means of hydrodynamic struggle with dust. Theoretically is established and experimentally confirmed, that for dust particles and liquid droplets in the process of pulse-wave interaction arise frequency ripple along with the changes of the amplitude of fluctuations in their pulses in the form of waves of pressure, which increases the effectiveness of the synergistic pulse shock interactions of liquid drops and particles in the process of their merger (dedusting). Professor Gogo VB noted that the longitudinal ripple components create the longitudinal wave, the energy maximum of which is proportional to the pulsation amplitudes liquid droplets, and particles of dust. Forecast of the probability of capture dust particles drops of fluid with consideration of the status of fractals binary system, then there is one drop of liquid can capture only one or two dust particles. Time of formation of the "land-drops" is the process time of the hydrodynamic dedusting. On the basis of the established patterns and characteristics of pulse-wave actions drops of liquid on the dust particles are designed installation, which was tested in the industrial conditions. The efficiency of their use for the improvement of working conditions of miners for the dust factor.[3]

3.2 Review of foreign means and methods of struggle with secretion dust in coal mines

As a foreign ways of dealing with the dust were the methods of control used in England, Germany, Russia. All the ways are different, and have nearly equal efficiency. In most studied innovations developed by these countries.

British scientists was presented by way of improvement of water dust suppression by using the supersonic system. Of the Russian considered the solution to combat dust released for the explosions. A new composition - wetting agents Republic of Poland for dust suppression during mass blasting in quarries on the basis of surface-active substances ethyl alcohol.

The main direction of scientific-research works of the German - improvement of R equipment and technology. One of such directions in the field of dust suppression is the competitive development of two types of moistening: jet and pressure with water jets. In mining company «Westfalen AG» concern «Ruhrkohle» developed pressure jet moistening slit slice, introduced in the majority of the company's mines.[18]

4. Methods of control used on the Novodzerzhinskaya mine

Novodzerzhinskaya mine was put into operation after reconstruction on the basis of the former mine №12-bis in 1981 with the commissioning of the horizon 502m (with a design capacity of 400 thousand tons a year).

In 1995 mine out of the production Association on coal mining «Dzerzhinskugol» with the subordination of the Ministry of coal industry of Ukraine (order no . 335 dated 12 October 1995).

The installed capacity of 230 thousand tons in a year.

On the balance sheet of the mines are 13 coal layers, of which 9 are accepted for processing: m3-0, 86m, l7-0, 92m, l5-0, 70m, l4-0, 65m, l4-0, 60m, l3-1, 65m, l2?-1, 06m, l2-0, 55, k8-1, 08m.

Mark coal-Well, partially - G.

The total number of industrial stocks -22,139 million tons.

The size of the mine fields along the strike - 3,5-5,0 km, in the fall - 2,8-3,2 km.


The distribution of the stocks on the horizon

Horizon The industrial reserves as at 01.01.2008, mils ton
530 m Developed
585 m 2350
645 m 2728
700-970 m 17061
All 22139

Stocks opened two vertical trunks of up to hor.645m and flanking the ventilation hole to hor.352m.

Main trunk passed to the depths of the 690m, with a diameter of 7m, mounted concrete underground supports a thickness of 500 mm. Equipped with twoskipovoy coal and twoskipovim species fluctuations.

Armirovka of the barrel - of-shaped executions, wires, and rail-P-43.

The lift is equipped with a lifting machine 2Ц6х2, 4 and skips capacity of 7, 1m3.

Rock climbing is equipped with a lifting machine 2Ц4х1, 8D and skips capacity of 4, 1m3.

Main trunk is intended for transfer of coal and breed with horizon 585м and release of the incoming air stream with separately ventilated workings: electric garage and warehouse VM.

The air handling unit the main shaft is equipped with two fans DSP-16B.

Auxiliary (cage) the completed to a depth of 665m, with a diameter of 7m, fastened concrete to the horizon 585m and below reinforced concrete underground supports a thickness of 500 mm. Equipped with two cage the rise of the machine 2Ц6х2, 4 and two-story cages 2УКН-3,2, as well as one end rise on the horizon 502m with the machine C2, 5х2 and a one-storey stand 1УКН-3, 3-3. Is intended for descent-lift people, materials, equipment and fresh air stream on гор.502m, 530m, 585m, 645m. Armirovka the trunk of the box-shootings, vehicles, rail R-43.

The ventilation hole passed to the horizon 352м, depth 314m, with a diameter of 3, 2m, Avenue of a metal tube with a wall thickness of 16 mm. Is designed for the issuance of incoming air stream from the mine and is equipped with a fan of the main airing of the WATER-21. Below (hor.352-530m) held ventilation сбойка on пл.l5 «Salty», is established metal arch underground supports.

Courts close to stem hor.502, 530, 585, 645m circular type.

At the present time is working off of stocks of horizon 585m.

Underground transport.

Removal of cargo on the horizontal developments are rechargeable electric locomotives of type AM-8D on a track of 600mm in cars WG-1,6, when траспортировке cargo on the developments with the outgoing air is used electric locomotives 7 ARV and shunting winches. Water drainage.

The normal flow of water in the mine 79 m3/h, the maximum flow of water 97m3/h. Water from the horizon of the 530m, 585m lower to the well d= 125mm on hor.645m.

From the horizon of the 645m water is pumped to the horizon 502m in the catchment basins of the main drainage and shall be issued to the surface. Drainage hor.645m is equipped with three hydraulic units of the Central nervous system 300х240, the capacity of the water condensers 800 m3, water drainage hor.502m - 3 pumping units to the Central nervous system 300х600, the capacity of the water condensers 1200m3.

The Novodzerzhinskaya mine all equipment morally obsolete. Used water injection in a coal array, irrigation and water screens.Shows the flow diagram of the discharge of the liquid in the coal array with the help of the pump unit.

Image 2 - the Technological scheme of the discharge of the liquid in the coal array using a pumping installation Dedusting air in a clearing face

To prevent the allocation and distribution of dust in abatement slaughter should be applied:

- irrigation during the excavation of coal;

- irrigation during loading of coal in the niches;

- irrigation at the loading point of the lava.

Dedusting of incoming and outgoing ventilation flows

For dedusting of the air stream, outgoing from the coal face in the mines, where there is swelling of the wall rocks, apply formation mist of the veil with the reduced consumption of the liquid. The fluid flow rate for the fogging of the veil - 0, 05l per 1m3 passing air at a pressure of 0,3-0,4 MPa.

The veil for dedusting air flow installed at a distance of not more than 20m away from the window of a lava on a direction of movement of the air.

Irrigators the fogging of the veil is installed so the cross-section of production was completely blocked torches sprayed liquid.

Conclusion

Almost every technological process at the mine accompanied by allocation of dust, which is a major source of morbidity miners ' pneumoconiosis, silicosis. Therefore, dust control is an integral and very important part of the technology of conducting mountain works. Above were presented as the main and the most common long applicable methods of struggle with the mining dust, and technologies finding in the development stage, or the recently introduced. A huge role in the creation of equipment for dust suppression played the principle incorporated in the development Venturi nozzles, typical for jet technology. However, it practically does not allow to achieve 100 % efficiency of dust suppression. Ukraine today is on the verge of a major restructuring, as in the organization, as well as in technical and technological provision of mountain works. Therefore, the experience of advanced European countries is extremely important and requires a comprehensive study and application in our environment.

Development of new methods and ways of coping with the dust, and the use of modern technologies allows to reduce secretion of dust in the mines and protect miners from such diseases, as pneumoconiosis, bronchitis, as well as many other related damage to the respiratory tract.

References

  1. Воровский А.А., Шлахов И.С. Влияние типа забойки на качество дробления и пылега-зоподавления при массовых взрывах на карьерах // Проблемы предотвращения загрязнения воздушного бассейна при открытой разработке железных руд.- Тезисы доклада Всесоюзн. научн-техн. семинара.-Кривой Рог.: ЦНИИЧМ, 1990.-С.31-32.
  2. Мельник Л.Г. Екологічна економіка: Підручник.- Суми: ВТД «Університетська книга», 2003.-348с.
  3. Гого В. Б. Диссертация и автореферат ДонНТУ, 2008.-280с.
  4. Научная статья "Фундаментальные свойства рассеивания пригодной для дыхания пыли и приостановленного вопроса макрочастицы" C. D. Litton, Присоединение: Питсбургская Научно-исследовательская лаборатория, Национальный Институт Профессиональной Безопасности и Здоровья 1-412-386-5167
  5. Смачивание пыли и контроль запыленности воздуха в шахтах / Р.Р. Кудряшов, Л.Д. Воронина,М.К. Шуринова и др. – М.: Наука, - 196 с.
  6. Физико-химические основы гидрообеспыливания и предупреждения взрывов угольной пыли /В.И. Саранчук, В.Н. Качан, В.В. Рекун и др. – К.: Наук. Думка, 1984. – 216 с.
  7. Медников Е.П. Турбулентный перенос и осаждение аэрозолей / Е.П. Медников. – М.: Наука,1980. – 176 с.
  8. Ищук И.Г. Средства комплексного обеспыливания горных предприятий: справочник / И.Г.Ищук, Г. А. Поздняков. – М.: Недра, 1991. – 223 с.
  9. Борьба с угольной и породной пылью в шахтах / П.М. Петрухин и др. – М.: Недра, 1981. – 271 с.
  10. Борьба с угольной пылью в высокопроизводительных забоях / под ред. Ф.С. Клебанова ; ИГДим. А.А. Скочинского. – М.: Недра, 1981. – 116 с.
  11. Кирин Б.Ф. Борьба с пылевыделением в шахтах / Б.Ф. Кирин, В.П. Журавлев, Л.И. Рыжих. – М.:Недра, 1983. – 213 с.
  12. Журавлев В.П. Применение гидрообеспыливания на предприятиях черной металлургии и в угольной промышленности / В.П. Журавлев, А.А. Цыцура, А.А. Кудрявцев. – Караганда, 1982. – 22 с.
  13. Разработка метода и программы расчета фракционной эффективности пылеулавливании при попутном капельном орошении / под рук. Пирумова А.И. // Сборник НИР и ОКР. – Серия 14, №31. – 47с.
  14. Поздняков Г. А. Теория и практика борьбы с пылью в механизированных подготовительных забоях / Г. А. Поздняков, Г.К. Мартынюк. – М.: Недра, 1983. – 126 с.
  15. Журавлев В.П. Исследование и расчет оросителей с регулируемой характеристикой / В.П. Журавлев, А.Х. Лоренц // Борьба с силикозом. – М.: Недра, 1982. – Т. ХI. – С. 67 – 71.
  16. Лойцянский Л.Г. Механика жидкости и газа / Л.Г. Лойцянский. – М.: Наука, 1970. – 914 с. Седов Л.И. Методы подобия и размерности в механике / Л.И. Седов. – М.: Наука, 1967. – 428с.
  17. С.Н. Александров, Ю.Ф. Булгаков, В.В. Яйло./ Охрана труда в угольной промышленности (учебное пособие для студентов горных специальностей высших учебных заведений)/. - Донецк.: ДонНТУ. 2005., 520с.
  18. Образовательно-научно-производственный портал «Рудана» http://www.rudana.in.ua/showanalit_11.htm