Perm Journal of Petroleum and Mining Engineering (Nov 2018)
Effective localization of coal dust explosions using hydro vortex coagulation
Abstract
The paper is devoted to the development of a mathematical model for high-pressure hydro vortex inertial kinematic dust suppression. The suppression can significantly improve the efficiency of localization of man-made accidents and reduce the level of occupational pulmonary diseases. The dynamics of improving the technology and technical means of dust suppression in the mining and metallurgical complex of Russia shows their lack of effectiveness in ensuring sanitary conditions, especially in localization of dust mixture explosions. A further increase in the efficiency of coal mining and mineral processing is significantly limited by the imperfection of the technology for localizing and eliminating explosions of coal dust. The method of high-pressure hydro vortex dedusting is developed based on the theory of attached vortices. A mathematical model of hydro vortex inertial, kinematic heterocoagulation, which significantly increases the energy efficiency of dust suppression, is proposed. The graphical model of the interaction in the contact zone at the time of the collision in the liquid-solid system is refined. Stokes and Reynolds criteria equations are obtained with hydro vortex inertial orthokinetic heterocoagulation. An equation is obtained which allows to calculate the magnitude of the reduction in the required energy of the total absorption of dust particles as a function of the circulation of liquid droplets. Equations for calculation of effective wetting angle and the minimum diameter of absorbed dust particles are obtained as a function of the angular velocity of rotation of liquid droplets. It is shown that hydro vortex coagulation significantly reduces the size of the dispersed dust composition, water consumption, increasing the efficiency of dust suppression. A significant decrease in the size of the absorbed dust particles increases the efficiency of localization of coal dust explosions, reduces the incidence of silicosis and anthracosis. Certification tests using patent-protected vortex nozzles confirmed that there was a reduction in the minimum size of absorbed dust in four times, increase in dust collection efficiency of up to 99 %, reduce in water consumption by 20 % compared to classic high-pressure spray cleaning. The proposed technology of dust suppression can be used in mining companies when fine explosive dust mixtures are formed.
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