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


temperature gradient for the kitchen space

The temperature gradient for the kitchen space Pirozhkova, etc. You can take a range of 1 to 1.2, but no more. Magnitude of the temperature gradient take depending on how the feed air supply and location of inlet nozzles or panels. The average temperature of the outgoing air are encouraged to take on 2-2,5 В° C above the working area.

In determining the supply air temperature in the warm period should take into account heating it in the fan.

Determining the amount of heat that must be removed general ventilation should take into account the heat carried away with the local air suction. The first takes into account the heat assimilated air being removed a veil over the stove. This amount of heat is determined by the expression

QM = LB {tp - ta) [kcal / h].

where / - supply air temperature.

Elektroskovorody and fryers must have a local suction. Typically, such a suction is arranged in the form of semiring slit in the side opposite to the workplace staff. Possible local suction through the suction panel, but it is less constructive. An umbrella over a pan or veil is not acceptable because it does not remove the hazard of breathing zone of the person.

Fig. 48 shows the removal of gases from elektroskovorody Semiring suction. Slit height of 50-60 mm is located at a distance of 80 - 100 mm above the rail pan or fryer. Speed aspirated taken within 4 - 5 m / sec.

You can recommend the following volumes of air removed local suction: from elektroskovorody low loading

L = 500 -: -700 m3 / h;
However, under intense frying
L = 600 -. 800 m3 / h;
from deep fryers with up to 50 liters
L = 800 1000 m3 / h.

From pastry ovens and elektrovypechnyh cabinets fume when opening doors and through cracks in the door closed. To capture these gases efficiently use umbrellas, canopies with side overhangs. Velocity in the horizontal section of the umbrellas with side overhangs taken in the range from 0,6 to 0,7 m / sec. Relocation of the umbrella-visor recommended order of 400 mm. With a length of 900 mm volume hood exhaust air
L = 3600 -0.9 -0.4 -0.6 = 800l3 / h.

We calculate the air in the kitchen serving the dining room with 200 seats under the following conditions.

Processing Equipment: plate number 1, two digesters at 250 hp. elektrovypechnoy rack capacity of 16.5 kW, boiler capacity of 200 l / h.

The height of the kitchen space of 4 m, 600 cubic m 3, the installed capacity of 5 kW mechanisms, teplopostuplenie of solar radiation by 1500 kcal / h. outdoor design temperature /, = +20 В° C (summer). Supply air is supplied at a height of 3 m from the floor perforated panel. The amount of air coming from the trading floor with / = +24 В° C, equal to 10,000 x3 /; Number of employees 5 people.

A cooker designed glazed curtain at elektrovypechnogo cabinet - an umbrella the size of 900X400 mm, elektroskovorody - semiring slot suction.

Volumes of air removed by local suction, the following: a parasol elektrovypechnogo cabinet - 800 m3 / h, through a slot suction from elektroskovorody - 700 m3/ch-
Heat from the stove Q i = 35 000 kcal / h.
Heat dissipation under the veil
Q3 = 0,75-35000 26,000 kcal / h.
Thermal room
Qn = 0,25-350009000 kcal / h.

The temperature in the working area is taken P = +25 В° C. The amount of air removed from the veil. For this catering should design the two-supply plant, one of which will serve retail space, and another - production. Exhaust installations planned five: one serves the trading floor, the second and third - cuisine (general exchange extraction and local pumps), and the fourth carries the hood of the other production and auxiliary facilities, and a fifth removes air from the restrooms and showers.