No abstract

The paper presents a number of mine ventilation schemes for variously located shaft collars and a main fan diffuser. The calculations of thermal drop of ventilation pressure in the inter-shaft area in each of the discussed variants involve the assessment of their effect on the mine pressure drop.Key words: natural draft, thermal drop of ventilation pressure, hydrostatic calculation method, altitude mark, diffuser, main mine fanThe natural draft or the thermal drop of ventilation pressure is an indispensable component of a mine's ventilation along with the main mine fan operation. The natural draft is generated because of the difference in air densities in mine shafts as is stated in [1,2]. The rock temperature is constant in a mine throughout a year, for example, the temperature of rocks at the Upper Kama Potassium Salt Deposit (UKPD) ranges within 7-9°С (8°С in average). Owning to the large extension of mine workings, the mine air temperature gets equal to the rock temperature, i.e., at the mine exit (in air shafts) the air temperature is also constant throughout the year. Consider the mine ventilation schematics in Fig. 1. In summer, when the outdoor temperature is above 8°С, the main mine fan supplies warm and lighter air into the air shaft ab, therefore, the cooler and heavier air is displaced from the air shaft cd. The resultant natural draft, directed from the air outlet shaft cd toward the air inlet shaft ab and toward the air flow Q; in other words, it counteracts the main mine fan operation. That natural draft is termed the "negative" draft (-h e ). Fig. 1. Mine ventilation layout.

No abstract

No abstract

Abstract-In the article, the options of mines aeration by means of ejector fan installation are examined, as well as the principle of this installation functioning and its potential are shown. Basing on the investigations conducted and the functioning results received, the possibility of application of the ejector fan installation as the main and auxiliary fan installation is shown. The application of the ejector fan installation as the main fan installation for aeration of the mines of the fields opened with adits or shafts of small extent on the northeast of Russia is proved. The option of using the ejector fan installation in the pit mouth as well as in underground stopings of the mine ventilating network is considered.Keywords-mine ventilating; main fan installations; ejector fan installations; underground mobile fan installation; aerodynamic drag