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


blasting compressed air corps

Blowing compressed air corps is sometimes made in the cabinet-type shelters with an inclined front wall, performed by Plexiglas. Opening in the shelter is the minimum size of 400x400 mm. Calculated air velocity in a section of the opening and leaks must be at least 2 m / sec.

Apparatus in which the backfilled dusty materials (powdered sugar, flour, etc.) should be provided with local suction. When filling in open vehicles (dralerovochnye boilers) local suction slot arranged horseshoe. Velocity in the gap should be the order of 7-10 m / sec, the height of the gap - 30-40 mm.

When backfilling of dusty materials in the open crater near the gap are arranged such pumps. The volume of exhaust air can be determined based on the norms of 7000 - 9000 m3 / h per 1 m2 of open funnel.

In the manufacture of biscuit dough are dusty and the prescription department. Here is allocated mostly to flour dust. While this dust is not toxic, the fight must be waged with her as with any dust. However, the confectionery is often ignored.

Hanging baking powders containing ammonium salts, performed in shelters, with exhaust air.

In the mass production of chocolate mixture is usually made in batch mixers - the so-called mix-machines. When you load them with powdered sugar operation is carried out with the lid closed - there has been intense ejection of dust into the room. To eliminate this phenomenon, should organize a local exhaustion of the mix of machines. Duct with aspiration funnel attached to the lid of the mixer parameters flexible hose with a diameter of 120 mm. With this hose the maximum amount of exhaust air 900 m3 / h. Is the amount of such suction, will practice.

In some cases, the confectionery factory produces hand-kneading the components, some of which are dusty substances (powdered sugar). The operation of kneading should be done in the immediate vicinity of the vertical suction panel. The amount of air removed the panel, should be given not less than 1500 m3 / h.

Dusty operations are also the grinding of cocoa, cocoa powder transport and packing. Milling equipment and transport equipment (augers, elevators, etc.) should be respectively sealed and aspirated.

Available in boxes of cocoa is produced, or manually, Fire on the machines. Manual packing should be carried out in shelters, cabinet or display cases, made of transparent material. The amount of air removed from the shelter, determined by calculating a speed in the working aperture of 1,2 - 1,3 m / sec.

While filling in the slots to avoid dusty areas best cover the entire machine in a casing with openings for maintenance workers, if it is of course possible by technological conditions. Less effective local shelters and pumps. In the latter case, the hiding place of loading cocoa into the machine and installed in the field of dust discharge pumps, funnels. These funnels are set at the following locations: at the place of filling in the boxes, where the volume of exhaust air should be 800-900 m3 / h at tryasuchek, where the volume of air exhausted 500-600 m3 / h at the site of the closing the box, where the volume of exhaust air 400 m3 / h. From the closet hiding in the place of loading cocoa machine, vacuum air in amounts not less than 2500 m3 / h at speeds in the openings of the order of 2 m / sec.

Dust in the confectionery valuable, it must be returned and recycled. This defines the specificity of dust collection. Wet scrubbers are not suitable.

Recapturing the sugar, flour and similar dust is usually performed on the suction cloth filters that are installed on the possible short distance from aspiriruemogo equipment. Fans should be installed in isolated areas-cells.

It should be borne in mind that sugar and flour dust and dust cocoa powder are explosive. Sugar dust is especially dangerous. When designing the aspiration systems that remove the powdered sugar, you must follow the rules for the systems deriving an explosive dust.

the premises chillers arranged general exchange ventilation to deal with pelvic hazards and excessive heat. In compressor ammonia plants in the allocation can be taken equal to 30 - 40 kkil / h na I kw of installed capacity. Number of released ammonia was adopted in 2000 g / h on a compressor capacity of up to 60 kilowatts, in the evaporation unit - - 30 g / h for one evaporator,

Indoor ammonia refrigeration minimum multiplicity of exchange in one hour is 2 for the influx, and 3 - on the hood. Provides for emergency extraction with multiplicity not less than 7 per hour.