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5 Main Ventilation
For all these reasons, this system is compulsory in many regulations mainly in coal
mining. In order to make the ventilation ascend, the downcast shaft must be at least
as deep as the upcast shaft so as to prevent part of the ventilation from descending.
Descensional ventilation is also possible when a more compact system is needed.
In this case, it is normal to also move the materials in the same direction to operate
in a homotropic system.
Exercise 5.7 The image represents the ventilation systems of two metal mines. The
following manometric pressures have been measured:
Scheme (a): −1200, 0, −2100, −720, −2400, −1500, (Pa)
Scheme (b): −680, 0, 0, 0, −500, 450 (Pa)
You are asked to:
(a) Indicate which type of ventilation system each figure corresponds to.
(b) Place the static and absolute pressures on the graph in their corresponding place.
Scheme (a)
5.Scheme (b)
5.Solution
5 Main Ventilation
For all these reasons, this system is compulsory in many regulations mainly in coal
mining. In order to make the ventilation ascend, the downcast shaft must be at least
as deep as the upcast shaft so as to prevent part of the ventilation from descending.
Descensional ventilation is also possible when a more compact system is needed.
In this case, it is normal to also move the materials in the same direction to operate
in a homotropic system.
Exercise 5.7 The image represents the ventilation systems of two metal mines. The
following manometric pressures have been measured:
Scheme (a): −1200, 0, −2100, −720, −2400, −1500, (Pa)
Scheme (b): −680, 0, 0, 0, −500, 450 (Pa)
You are asked to:
(a) Indicate which type of ventilation system each figure corresponds to.
(b) Place the static and absolute pressures on the graph in their corresponding place.
Scheme (a)
5.Scheme (b)
5.Solution