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


Guidance on design temperature evaporation

Standards and guides, recommending a significant increase in the estimated surface for wet rough material, do not give any indication of the design temperature of evaporation. Use the data for the quiet surface of the liquid in this case correctly, as the evaporating temperature will be lower, but how much is hard to say because it depends on the structure of the material, actual and estimated the degree of roughness, etc. With certain approximation we can assume that the temperature evaporation 20% lower than presented in tables for quiet fluid.

While pouring the hot water and drip it on the floor is difficult to define and surface evaporation, and its average temperature (or the final temperature before the runoff in the sewer). It is best to be based on actual measurements. If the wetted area is more or less definite, the temperature can be determined by trial calculations. The amount of water that evaporates from the wetted surface of the floor, under certain initial and final temperatures can be determined by the formula

G = (a-y) [kg / h], (19)

where Gc - the amount of hot water falling on the floor, in kg / h;

tr - leaky hot water temperature in В° C;

ty - the final temperature of water entering the sewage system, in В° C.

The formula (18) is the air velocity over the surface evaporation. Neither references nor ham in the rules that speed is not given. Advised to take the following values of the velocity V.

for air moving naturally,

v - 0,3 -: - 0,4 m / sec;

for air moving force (air suction, the proximity of inlet jets, etc.) and 0,0 m / sec;

Evaporation from a surface cold water (wet-bulb temperature) is recommended to use the formula

W = Sb. [Kg / h], (20)

where f,. - Temperature dry bulb; / m - the temperature on the wet bulb temperature; F - surface evaporation in m2.

For the calculation of the boiling liquid evaporation from the formula (18) gives incorrect results. According to prof. V. Baturin, in boiling water with 1 M1 mirror evaporation is allocated to 50 kg/m2Ch, with vigorous boiling - even more so in this case the amount of water evaporated is calculated by the number of heat input.

Amount of water vapor entering the room through leaks in pipes and fittings, and also formed by chemical reactions, this is the practical data, taken from the technology.