Air pollution in industrial enterprises

Airborne pumps

basic principle of ventilation

Centrifugal exhaust veshilyatory

Determination of air exchange

dust control

Exhaust System

Forced ventilation on confectionery

Hourly values

mist of water vapor

pressure loss in the flare emissions

radioactive dust

scheme of the central pressure inlet system

Special prechamber

temperature gradient

Ventilation at bakeries

Ventilation in the Confectionery Factory

ventilation when dealing with heat


Dresser With Mirror

temperature gradient

In the same room temperature gradient is different for different points of the room. The values of A used by the calculations should be regarded as some average value.

Table. 16 shows the values of the temperature gradient and depending on the heat-stressed in the room and the height of the building. These figures should be seen as indicative subject to confirmation in each particular case, for example, depending on the location of heat sources. Table. 16 drawn for the scattered inflow into the lower zone. When the jet flow, direction even in the work zone due to air mixing gradient A is dramatically reduced. In some cases, it becomes zero.

Given the proximity in determining the air, perhaps in the calculation of heat release handle with rounded figures.

In the formulas for calculating air (41) and (42) contains the quantity Qj, ie, the amount of heat carried away by the air being removed from the work area. This value is calculated by the expression

<2p .. = В° .24 ip., (
Value / P.3 accepted the norms of meteorological conditions for industrial premises, described in SI 245-63. Supply air temperature in each particular case is chosen by the designer, since the exact specifications for it does not. Typically, supply air temperature is taken depending on the temperature of the working area. When dealing with heat is always less than 1P tp.a:

For fresh air introduced into the working area, with the aeration device, take A / = 5-f-8 В° C for the transition and A = 8 В° C - for the winter.

In mechanical flow fed into the work zone, we recommend the following quantities At, В° C:

feeding scattered inflow with low velocities:

away from jobs ....... 7-10
near jobs ........... 5-7
feeding scattered with significant inflow velocities (0,7-1,2 m / s CCK):
away from jobs ....... 6-Y
near jobs ........... 4-6
when the jet flow ............ 10-12

Supply air temperature is not recommended below +14 В° C for light work and +8 В° C - with a heavy.

When injection of air into the upper zone temperature can be taken much lower than this, depending on the height and the method feeder. The value of A can reach 15 - 20 В° C.