Ventilation at bakeries
The main hazard breadmaking - excess heat and moisture. Dust emission are available, but they are insignificant. Flour dust is relatively harmless, struggle with it no problem. Gazovydelenpya, fogs and aerosols in bakeries almost never occur. Discharge from the bakery and konditerskihpechey so insignificant that almost no role. Due to the above ventilation bakeries mostly general exchange.
Despite the fact that the main harm to the bakery - the excess heat, aeration facilities are unacceptable. Like most food companies for production facilities to supply air dedusting.
Sanitary and technical considerations on the one hand and the difficulty of natural ventilation - the other did not allow the use of aeration, even in the warm season. Ventilation bakeries, as a rule, supply and exhaust with a mechanical inflow and a mixed extract.
The mechanical flow of purified air from dust in all seasons is needed for areas such as hlebohranilische and forwarding, bakery department, pastry shop and barns, Doughnuts shop. For other premises allowed the supply air flow naturally in the warm period. However, the correct design flow of filtered air to all rooms.
Forced ventilation in the warm season in the most rational solved by beskalorifernyh installations only when the outside temperature of +10 В° C and above. These settings are calculated on the supply of additional air, the need for a warm period. The bulk of the air comes from conventional air handling systems that operate year-round.
Supply plant, designed to work only in the summer, usually consist of an air intake device (grille and air intake valve with manual control), oil filter n axial fan. Scheme of such a supply plant is shown in Fig. 44. The system has no air and delivers a concentrated air stream. Insulated valve is required to disable the PA system during winter.
The windows of bakeries are supplied with opening transoms, which, however, open only during the hot hours, when the outdoor temperature is greater than the estimated for the warm period (parameter A). At lower temperatures, transoms trench and exterior doors must be closed.
Basically, the production shop, which includes heating the room, and in the combustion compartment, where there is considerable heat and gas evolution are practically absent, acceptable air recirculation. Air handling the installation of these facilities. May be purely recirculation or partial-heated outdoor air into the radiator and heated it by mixing with return air. Depending on local conditions sometimes refuse recycling and fully heated air into the radiator.
In large rooms should be made air lumped jets. In small rooms, the air is usually served in a work area with air distributors. In the dusty air is fed into the upper zone of perforated panels.
General exchange extract made from the upper zone of mainly naturally mines PLI deflectors. It is very much to attend to the condensate in order to avoid the drops from the mines.
Local bakeries on the pumps are scarce. In addition to suction from dusting equipment, local pumps are arranged at the boarding and unloading furnaces and windows of the washing baths.
With bulk storage of flour in splosah transport flour by roughly following the scheme shown in Fig. 45.
From flour millers will yield in silos pneumatically. From the silo through the feeder meal enters the peg and the elevator rises in podvesovoy bunker. Then flour weigh portions automatic weights through podvesovoy hopper falls into the sifter type Burat with separator.
Sifted flour goes into the bunker, where necessary, but as dough is fed into the unit. Instead of screws and pneumatic elevators are sometimes used.
Avoid dusting flour tract should be aspirated. Given the properties of flour dust and the low intensity of dusting with flour extraction path, the volume of air removed by aspiration, are usually made slightly smaller than in other industries.
Installation of pneumatic, feed flour silos, should have the product separators and filters. For localization of dust emission should suck air from the silos aspiration system. Suction is made from all the silos, regardless of the mode of their work. Should not be installed on the aspiration duct disable bodies (dampers).
Can recommend the following volumes of air (m3 / h). which must be removed in the aspiration tract flour;